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  • Question 1 - A new chemotherapy drug is being tested. The intervention reduces the risk of...

    Incorrect

    • A new chemotherapy drug is being tested. The intervention reduces the risk of death from 10 in 1000 to 5 in 1000. What is the number needed to treat to prevent one death:

      Your Answer: 15

      Correct Answer: 200

      Explanation:

      Absolute risk reduction (ARR) of treatment
      = risk of death in control group – risk of death in treatment group
      ARR = (10/1000) – (5/1000)
      = 5/1000 = 0.005
      Number needed to treat (NNT)
      = 1/ARR
      = 1/0.005
      = 200
      Therefore 200 people would need to be treated to prevent one extra death.

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Statistics
      7
      Seconds
  • Question 2 - The syndrome of inappropriate antidiuresis due to excessive antidiuretic hormone (ADH) secretion is...

    Correct

    • The syndrome of inappropriate antidiuresis due to excessive antidiuretic hormone (ADH) secretion is diagnosed in a male patient with a history of recurrent hyponatraemia.

      Which of the following produces ADH?

      Your Answer: Hypothalamus

      Explanation:

      Antidiuretic hormone (ADH), commonly known as vasopressin, is a peptide hormone that controls how much water the body retains.

      It is produced in the magnocellular and parvocellular neurosecretory cells of the paraventricular nucleus and supraoptic nucleus in the hypothalamus from a prohormone precursor. It is subsequently carried to the posterior pituitary via axons and stored in vesicles.

      The secretion of ADH from the posterior pituitary is regulated by numerous mechanisms:
      Increased plasma osmolality: Osmoreceptors in the hypothalamus detect an increase in osmolality and trigger ADH release.

      Stretch receptors in the atrial walls and big veins detect a decrease in atrial pressure as a result of this (cardiopulmonary baroreceptors). ADH release is generally inhibited by atrial receptor firing, but when the atrial receptors are stretched, the firing reduces and ADH release is promoted.
      Hypotension causes baroreceptor firing to diminish, resulting in increased sympathetic activity and ADH release.
      An increase in angiotensin II stimulates angiotensin II receptors in the hypothalamus, causing ADH production to increase.

      The main sites of action for ADH are:
      The kidney is made up of two parts. ADH’s main job is to keep the extracellular fluid volume under control. It increases permeability to water by acting on the renal collecting ducts via V2 Receptors (via a camp-dependent mechanism). This leads to a decrease in urine production, an increase in blood volume, and an increase in arterial pressure as a result.

      Vascular system: Vasoconstriction is a secondary function of ADH. ADH causes vasoconstriction via binding to V1 Receptors on vascular smooth muscle (via the IP3 signal transduction pathway). An increase in arterial pressure occurs as a result of this.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      25
      Seconds
  • Question 3 - A 45-year old man presented to the emergency room with complains of chest...

    Incorrect

    • A 45-year old man presented to the emergency room with complains of chest pain and breathlessness. Upon history taking and examination, it was discovered that he had a right-sided spontaneous pneumothorax and had a failed attempt at pleural aspiration. The pneumothorax is still considerable in size, but he remains breathless. A Seldinger chest drain was inserted but it started to drain frank blood shortly after.

      Which of the following complications is most likely to have occurred?

      Your Answer: Pulmonary laceration

      Correct Answer: Intercostal artery laceration

      Explanation:

      Injury to the intercostal artery (ICA) is an infrequent but potentially life-threatening complication of all pleural interventions.

      Traditional anatomy teaching describes the ICA as lying in the intercostal groove, protected by the flange of the rib. This is the rationale behind the recommendation to insert needles just above the superior border of the rib. Current recommendations for chest drain insertion suggest that drains should be inserted in the ‘safe triangle’ in order to avoid the heart and the mediastinum and be above the level of the diaphragm.

      The safe triangle is formed anteriorly by the lateral border of the pectoralis major, laterally by the lateral border of the latissimus dorsi, inferiorly by the line of the fifth intercostal space and superiorly by the base of the axilla. Imaging guidance also aids in the safety of the procedure.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      9.7
      Seconds
  • Question 4 - Which of the following antibiotics is the first line of treatment for a...

    Incorrect

    • Which of the following antibiotics is the first line of treatment for a patient who has been diagnosed with chlamydia infection?

      Your Answer: Ciprofloxacin

      Correct Answer: Azithromycin

      Explanation:

      The Centres for Disease Control and Prevention (CDC) recommends azithromycin, a single 1 g dose, and doxycycline, 100 mg bd for 7 days, as first-line medications for chlamydial infection treatment.

      Second-line medications (such as erythromycin, penicillins, and sulfamethoxazole) are less effective and have more side effects

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      7.6
      Seconds
  • Question 5 - A 29-year-old man presents with painful red eye with copious discharge and you...

    Incorrect

    • A 29-year-old man presents with painful red eye with copious discharge and you make a diagnosis of infective conjunctivitis following a history and an examination,.

      One of these is NOT an indication for an urgent ophthalmology referral in this patient.

      Your Answer: Conjunctivitis associated with rheumatoid arthritis

      Correct Answer: Bilateral conjunctivitis

      Explanation:

      Urgent referral to ophthalmology is indicated if the patient with conjunctivitis has any of the following:

      Suspected gonococcal or chlamydial conjunctivitis
      Corneal involvement associated with soft contact lens use
      Severe disease indicated by presence of a pseudomembrane
      Conjunctivitis associated with rheumatoid arthritis or in immunocompromised patient. Ophthalmia neonatorum.
      Possible herpes infection.
      Had recent intraocular surgery. A red flag indicating a serious cause of red eye.
      Suspected periorbital or orbital cellulitis.

      Bilateral conjunctivitis is not an indication for urgent referral to ophthalmology.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      7.7
      Seconds
  • Question 6 - Which of the following does NOT typically cause a neutrophil leucocytosis: ...

    Incorrect

    • Which of the following does NOT typically cause a neutrophil leucocytosis:

      Your Answer: Acute appendicitis

      Correct Answer: Glandular fever

      Explanation:

      Causes of neutrophil leucocytosis:
      Bacterial infection
      Inflammation and tissue necrosis (e.g. cardiac infarct, trauma, vasculitis, myositis)
      Metabolic disorders (e.g. uraemia, acidosis, eclampsia, gout)
      Pregnancy
      Acute haemorrhage or haemolysis
      Neoplasms of all types
      Drugs (e.g. corticosteroid therapy, lithium, tetracyclines)
      Asplenia
      Myeloproliferative disorders (e.g. CML, essential thrombocythaemia, polycythaemia vera, myelofibrosis)
      Rare inherited disorders

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      21
      Seconds
  • Question 7 - Which of the following laboratory findings are indicative of von Willebrand disease (VWD):...

    Correct

    • Which of the following laboratory findings are indicative of von Willebrand disease (VWD):

      Your Answer: Prolonged APTT

      Explanation:

      Laboratory results often show that:
      PFA-100 test results are abnormal.
      Low levels of factor VIII (if a factor VIII/VWF binding assay is conducted)
      APTT is Prolonged (or normal)
      PT is normal
      VWF values are low.
      Defective Platelet aggregation
      The platelet count is normal.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      5.4
      Seconds
  • Question 8 - Foetal haemoglobin (HbF) comprises about how much of the total haemoglobin in adults:...

    Incorrect

    • Foetal haemoglobin (HbF) comprises about how much of the total haemoglobin in adults:

      Your Answer: 3 - 5%

      Correct Answer: 0.5 - 0.8%

      Explanation:

      Foetal haemoglobin (HbF) makes up about 0.5 – 0.8 % of total adult haemoglobin and consists of two α and two gamma (γ) globin chains.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      35.5
      Seconds
  • Question 9 - If the ejection fraction increases, there will be a decrease in: ...

    Incorrect

    • If the ejection fraction increases, there will be a decrease in:

      Your Answer: Stroke volume

      Correct Answer: End-systolic volume

      Explanation:

      An increase in ejection fraction means that a higher fraction of the end-diastolic volume is ejected in the stroke volume (e.g. because of the administration of a positive inotropic agent). When this situation occurs, the volume remaining in the ventricle after systole, the end-systolic volume, will be reduced. Cardiac output, stroke volume, and mean arterial pressure will be increased.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      8.4
      Seconds
  • Question 10 - Which of the following is NOT a characteristic of megaloblastic anaemia? ...

    Incorrect

    • Which of the following is NOT a characteristic of megaloblastic anaemia?

      Your Answer: Increased lactate dehydrogenase (LDH) level

      Correct Answer: Raised reticulocyte count

      Explanation:

      The LDH level is usually markedly increased in severe megaloblastic anaemia. Reticulocyte counts are inappropriately low, representing a lack of production of RBCs due to massive intramedullary haemolysis. These findings are characteristics of ineffective haematopoiesis that occurs in megaloblastic anaemia as well as in other disorders such as thalassemia major.
      The common feature in megaloblastosis is a defect in DNA synthesis in rapidly dividing cells. To a lesser extent, RNA and protein synthesis are impaired. Unbalanced cell growth and impaired cell division occur since nuclear maturation is arrested. More mature RBC precursors are destroyed in the bone marrow prior to entering the bloodstream (intramedullary haemolysis).

    • This question is part of the following fields:

      • Haematology
      • Pathology
      8
      Seconds
  • Question 11 - A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration...

    Incorrect

    • A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration is 1246 pg/mL.
      Glucagon is produced in which of the following cells? Select ONE answer only.

      Your Answer: Beta-cells in the pancreas

      Correct Answer: Alpha-cells in the pancreas

      Explanation:

      Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
      Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
      Glucagon then causes:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.

      Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      31.6
      Seconds
  • Question 12 - Regarding Clostridium tetani, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding Clostridium tetani, which of the following statements is CORRECT:

      Your Answer: It is not found in normal intestinal flora.

      Correct Answer: Infection is predominantly derived from animal faeces and soil.

      Explanation:

      Clostridium tetaniis a Gram positive, rod shaped, obligate anaerobic bacterium.
      The incubation period is quoted as anywhere between 4-21 days and can occur after several months but symptoms usually occur within the first 7 days after exposure.
      Approximately 80% of patients develop generalised tetanus. The commonest presenting feature of generalised tetanus is trismus (lockjaw), occurring in approximately 75% of affected individuals. Other clinical features include:
      Facial spasms (risus sardonicus)
      Opisthotonus (characteristic body shape during spasms)
      Neck stiffness
      Dysphagia
      Calf and pectoral muscle rigidity
      Fever
      Hypertension
      Tachycardia
      Spasms can occur frequently and last for several minutes, they can continue to occur for up to 4 weeks. Current mortality rates are between 10 and 15%.
      Tetanic spasms are caused by the exotoxin tetanospasmin. The effects of tetanolysin are not fully understood but it is not believed to have clinical significance.
      Localised tetanus is a rare form of the disease, occurring in around 1% of affected individuals. Patients have persistent contraction of muscles in the same anatomic area as the injury. It may precede generalised tetanus.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      14.7
      Seconds
  • Question 13 - Nitric oxide release from endothelium is stimulated by all of the following EXCEPT...

    Incorrect

    • Nitric oxide release from endothelium is stimulated by all of the following EXCEPT for:

      Your Answer: Substance P

      Correct Answer: Noradrenaline

      Explanation:

      Nitric oxide (NO) production by the endothelium is increased by factors that elevate intracellular Ca2+, including local mediators such as bradykinin, histamine and serotonin, and some neurotransmitters (e.g. substance P). Increased flow (shear stress) also stimulates NO production and additionally activates prostacyclin synthesis. The basal production of NO continuously modulates vascular resistance; increased production of nitric oxide acts to cause vasodilation. Nitric oxide also inhibits platelet activation and thrombosis.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      25.5
      Seconds
  • Question 14 - In the Paediatric Emergency Department, you saw a 6-year-old girl with severe bilateral conjunctivitis....

    Incorrect

    • In the Paediatric Emergency Department, you saw a 6-year-old girl with severe bilateral conjunctivitis. You give her mother some general eye hygiene advice and prescribe chloramphenicol eye drops.

      What is the chloramphenicol's mechanism of action?

      Your Answer: Inhibition of cell wall synthesis

      Correct Answer: Inhibition of protein synthesis

      Explanation:

      Chloramphenicol is a broad-spectrum antibiotic that inhibits bacterial protein synthesis by blocking the 50S subunit of the bacterial ribosome’s peptidyl transferase activity. When administered systemically, it has limited usage due to the potential of significant side effects such as aplastic anaemia, peripheral neuropathy, and optic neuritis. It’s only used to treat typhoid fever and Haemophilus influenzae meningitis, but it’s usually better to use a broad-spectrum cephalosporin.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      51.2
      Seconds
  • Question 15 - A 40-year-old woman presents with a fever and headache upon returning from an...

    Incorrect

    • A 40-year-old woman presents with a fever and headache upon returning from an overseas business trip. Upon further investigation, a diagnosis of Plasmodium falciparum malaria was made.

      All of the following statements is considered true regarding Plasmodium falciparum malaria, except:

      Your Answer: Sporozoites invade hepatocytes

      Correct Answer: It is commonly the result of travel in the Indian subcontinent

      Explanation:

      The mean incubation period for P. falciparum is 12 days.

      WHO World Malaria Report 2019 states that an estimated 228 million cases of malaria occurred worldwide in 2018, and reports steadily decreasing the number of cases since 2010. In 2018, nineteen sub-Saharan African countries and India carried approximately 85% of the global malaria burden. The most prevalent and pathogenic malaria parasite, most commonly associated with severe illness and death, especially in the WHO African region, accounting for 99.7% malaria cases, is P. falciparum.

      The vector for Plasmodium spp. is a female Anopheles mosquito that inoculates sporozoites contained in her salivary glands into the puncture wound when feeding. Sporozoites enter peripheral bloodstream and are uptake by hepatocytes, where they undergo an asexual pre-erythrocytic liver-stage as liver schizonts lasting up to 2 weeks before the onset of the blood stage.

      Intravenous or intramuscular artesunate is the first-line treatment in all patients worldwide and should be used for at least 24 hours and until the oral medication is tolerated.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      27.2
      Seconds
  • Question 16 - A 70-year-old man presents with right-sided hemiplegia and loss of joint position sense,...

    Incorrect

    • A 70-year-old man presents with right-sided hemiplegia and loss of joint position sense, vibratory sense, and discriminatory touch. Upon further physical examination, it was observed that her tongue deviates to the left-hand side. An MRI and CT scan was ordered and results showed that he was suffering a left-sided stroke.

      Branches of which of the following arteries are most likely implicated in the case?

      Your Answer: Posterior spinal artery

      Correct Answer: Anterior spinal artery

      Explanation:

      Medial medullary syndrome is a form of stroke that affects the medial medulla of the brain. It is caused by a lesion in the medial part of the medulla, which is due to an infraction of vertebral arteries and/or paramedian branches of the anterior spinal artery.

      It is characterized by contralateral paralysis of the upper and lower limb of the body, a contralateral decrease in proprioception, vibration, and/or fine touch sensation, paresthesias or less commonly dysesthesias in the contralateral trunk and lower limb, and loss of position and vibration sense with proprioceptive dysfunction. Ipsilateral deviation of the tongue due to ipsilateral hypoglossal nerve damage can also be seen.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      5.5
      Seconds
  • Question 17 - A patient presents with acute severe asthma. Her initial salbutamol nebulization produced a...

    Correct

    • A patient presents with acute severe asthma. Her initial salbutamol nebulization produced a poor response and you administer another nebuliser with ipratropium bromide added on.

      Which statement about ipratropium bromide is true?

      Your Answer: It can trigger acute closed-angle glaucoma

      Explanation:

      Ipratropium bromide is an antimuscarinic drug. It is used in the management of acute asthma and COPD.

      It provides short-term relief in chronic asthma. Short-acting β2agonists are preferred and act more quickly.

      The commonest side effect of ipratropium bromide is dry mouth. Tremor is commonly seen with β2agonists.

      It can trigger acute closed-angle glaucoma in patients that are susceptible.

      First-line treatment for moderate asthma attacks is short-acting β2agonists.

      The BTS guidelines recommend that nebulised ipratropium bromide (0.5 mg 4-6 hourly) be added to β2agonist treatment in patients with a poor initial response to β2agonist therapy or with acute severe or life-threatening asthma.

      Its duration of action is 3-6 hours, maximum effect occurs 30-60 minutes after use, and bronchodilation can be maintained with three times per day dosing.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
      6.7
      Seconds
  • Question 18 - A 23-year-old student presents to the emergency department with a terrible headache, photophobia,...

    Incorrect

    • A 23-year-old student presents to the emergency department with a terrible headache, photophobia, and a fever. On her lower limbs, you see a non-blanching purpuric rash. In the department, a lumbar puncture is conducted. What do you think you'll notice on Gram stain:

      Your Answer: Gram positive coccobacilli

      Correct Answer: Gram negative diplococci

      Explanation:

      Bacterial meningitis and septicaemia are most commonly caused by meningococcal bacteria. The Gram-negative diplococci Neisseria Meningitidis causes meningitis. Gram stain and culture of CSF identify the etiologic organism, N meningitidis. In bacterial meningitis, Gram stain is positive in 70-90% of untreated cases, and culture results are positive in as many as 80% of cases.

    • This question is part of the following fields:

      • Infections
      • Microbiology
      4.7
      Seconds
  • Question 19 - The average BP reading on ambulatory blood pressure monitoring for a 59-year-old Caucasian...

    Incorrect

    • The average BP reading on ambulatory blood pressure monitoring for a 59-year-old Caucasian man is 152/96 mmHg (ABPM).

      The first-line drug treatment for this patient would be which of the following? Please only choose ONE answer.

      Your Answer: Ramipril

      Correct Answer: Amlodipine

      Explanation:

      An ambulatory blood pressure reading of >150/95 is classified as stage 2 hypertension, according to the NICE care pathway for hypertension, and the patient should be treated with an antihypertensive drug.

      A calcium-channel blocker, such as amlodipine, would be the most appropriate medication for a 59-year-old Caucasian man.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      9.3
      Seconds
  • Question 20 - Which of the following statements regarding forest plots is true? Select ONE answer...

    Correct

    • Which of the following statements regarding forest plots is true? Select ONE answer only.
      Which of the following statements regarding forest plots is true? Select ONE answer only.

      Your Answer: Larger studies are associated with smaller horizontal lines

      Explanation:

      Forest plots are graphical displays designed to illustrate the relative strength of treatment effects in multiple individual studies addressing the same question.

    • This question is part of the following fields:

      • Evidence Based Medicine
      25.8
      Seconds
  • Question 21 - After what time period should intravenous phenytoin be used as second-line treatment of...

    Incorrect

    • After what time period should intravenous phenytoin be used as second-line treatment of status epilepticus?

      Your Answer: 30 minutes

      Correct Answer: 25 minutes

      Explanation:

      If seizures recur or fail to respond after initial treatment with benzodiazepines within 25 minutes of onset, phenytoin sodium, fosphenytoin sodium, or phenobarbital sodium should be used.

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      32.5
      Seconds
  • Question 22 - An injury to the brachial plexus can cause Erb's palsy. The following is...

    Incorrect

    • An injury to the brachial plexus can cause Erb's palsy. The following is expected to happen to a patient suffering from this condition, except for which one:

      Your Answer: Weakness of supination of the forearm

      Correct Answer: Weakness of medial rotation of the arm

      Explanation:

      Erb’s palsy can be caused by a traumatic force downward on the upper arm and shoulder that damages the upper root of the brachial plexus.

      The patient will lose shoulder abduction (deltoid, supraspinatus), shoulder external rotation (infraspinatus), and elbow flexion as a result of this condition (biceps, brachialis).

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      11.4
      Seconds
  • Question 23 - Regarding red blood cell group antigens and antibodies, which of the following statements...

    Incorrect

    • Regarding red blood cell group antigens and antibodies, which of the following statements is CORRECT:

      Your Answer: Naturally occurring anti-D antibodies occur in the plasma of all subjects who lack the RhD antigen.

      Correct Answer: Anti-D antibodies are usually IgG.

      Explanation:

      Approximately 400 red blood cell group antigens have been described. The ABO group antigens are unusual in that naturally occurring antibodies occur in the plasma of subjects who lack the corresponding antigen, even if they have not been exposed to that antigen previously. The most important of these natural antibodies are anti-A and anti-B, which are usually IgM. Anti-D antibodies don’t occur naturally, and are therefore immune antibodies that result from previous transfusions or pregnancy. Only IgG antibodies are capable of transplacental passage and the most important immune antibody is the Rh antibody, anti-D.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      6.9
      Seconds
  • Question 24 - A 6-year-old female is brought to the Ophthalmology Clinic by her mother with...

    Incorrect

    • A 6-year-old female is brought to the Ophthalmology Clinic by her mother with the complaint of itching, redness, and a watery discharge of the right eye. Past medical history revealed an upper respiratory tract infection one week ago.

      On examination of the right eye, there is mild erythema of the palpebral conjunctiva and visible follicles seen on eversion of the eyelid, lid oedema, and subconjunctival petechial haemorrhages. The discharge is watery and not purulent.

      You diagnose her with viral conjunctivitis. According to the current NICE guidelines, which ONE of the following management options would NOT be included for this patient?

      Your Answer: Antibiotic prescription should be avoided

      Correct Answer: The child should be excluded from school until the infection has resolved

      Explanation:

      The NICE guidelines do NOT recommend isolating a patient with viral conjunctivitis from others or skipping school or work. The disease is contagious, but the spread of the disease can be controlled by maintaining good hygiene practices such as:
      1. frequent hand washing
      2. use of separate flannels and towels
      3. Avoid close contact with others

      Antibiotic prescriptions are not part of the NICE guidelines for viral conjunctivitis as they will not affect the course of the disease. Most cases of viral conjunctivitis are self-limiting and resolve within one to two weeks.

      The NICE guidelines recommend that symptoms may be eased with self-care measures such as:
      1. Bathing/cleaning the eyelids with cotton wool soaked in sterile saline or boiled and cooled water to remove any discharge
      2. Cool compresses applied gently around the eye area
      3. Use of lubricating drops or artificial tears

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      4.4
      Seconds
  • Question 25 - A 6 year old boy is brought into the ED by his mom...

    Correct

    • A 6 year old boy is brought into the ED by his mom with a rash that is associated with Koplik's spots and a diagnosis of measles is made. What advice should be given about returning to school?

      Your Answer: 4 days from the onset of the rash

      Explanation:

      Prevention of spread of measles is extremely important and infected patients should be isolated. The infectious stage is from 3 days before the rash emerges and patients are advised to stay away from school/nursery/work for 4 days from onset of the rash.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      7.3
      Seconds
  • Question 26 - A suicidal patient had lacerated his wrist, which resulted in an ulnar nerve...

    Correct

    • A suicidal patient had lacerated his wrist, which resulted in an ulnar nerve injury. Which of the following will confirm the presence of an ulnar nerve injury?

      Your Answer: Claw hand appearance

      Explanation:

      An ulnar injury may result in abnormal sensations in the little finger and ring finger, usually on the palm side, weakness, and loss of coordination of the fingers.

      A claw like deformity of the hand and wrist is present. Pain, numbness, decreased sensation, tingling, or burning sensation in the areas controlled by the nerve are also possible.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      17.6
      Seconds
  • Question 27 - The ventilation over perfusion ratio is highest at the apex of the lung....

    Incorrect

    • The ventilation over perfusion ratio is highest at the apex of the lung. What is the approximate V/Q ratio at this area?

      Your Answer: 0.35

      Correct Answer: 3.3

      Explanation:

      The ventilation/perfusion ratio (V/Q ratio) is a ratio used to assess the efficiency and adequacy of the matching ventilation and perfusion. The ideal V/Q ratio is 1.

      Any mismatch between ventilation and perfusion will be evident in the V/Q ratio. If perfusion is normal but ventilation is reduced, the V/Q ratio will be less than 1, whereas if ventilation is normal, but perfusion is reduced, the V/Q ratio will be greater than 1.

      If the alveoli were ventilated but not perfused at all, then the V/Q ratio would be infinity. The V/Q ratio is also affected by location. The various areas of the lungs have a different V/Q ratio since ventilation and perfusion increase from the apex to the base of the lungs. The apex of the lungs has a V/Q ratio of approximately 3.3.

    • This question is part of the following fields:

      • Physiology
      • Respiratory Physiology
      8
      Seconds
  • Question 28 - You examine a patient who is experiencing a worsening of his chronic heart...

    Correct

    • You examine a patient who is experiencing a worsening of his chronic heart failure. You discuss his care with the on-call cardiology registrar, who recommends switching him from furosemide to bumetanide at an equivalent dose. He's on 80 mg of furosemide once a day right now.

      What is the recommended dose of bumetanide?

      Your Answer: 2 mg

      Explanation:

      Bumetanide is 40 times more powerful than furosemide, and one milligram is roughly equivalent to 40 milligrams of furosemide. This patient is currently taking 80 mg of furosemide and should be switched to a 2 mg bumetanide once daily.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      20.6
      Seconds
  • Question 29 - Epigastric pain and haematemesis present in a 67-year-old man. In the emergency room,...

    Incorrect

    • Epigastric pain and haematemesis present in a 67-year-old man. In the emergency room, he is stabilised and referred to the on-call medical team. He has been scheduled for an endoscopy in the morning due to a suspected peptic ulcer. Before transferring him to the ward, you consider giving him a proton pump inhibitor (PPI).

      Which of the following doses and routes are the best?

      Your Answer: Omeprazole 40 mg orally

      Correct Answer: A PPI should not be prescribed

      Explanation:

      PPIs should not be used prior to endoscopic therapy when an early endoscopic examination is performed within 24 hours of admission, according to current recommendations.
      High-dose PPI therapy reduces the risk of rebleeding and surgery after endoscopic treatment of severe peptic ulcer bleeding. Both oral and intravenous PPIs produce similar results, and there is no discernible benefit to using the intravenous formulation in patients who can tolerate oral medication.

    • This question is part of the following fields:

      • Gastrointestinal Pharmacology
      • Pharmacology
      4
      Seconds
  • Question 30 - At rest, saliva is produced predominantly by which of the following: ...

    Incorrect

    • At rest, saliva is produced predominantly by which of the following:

      Your Answer: Minor salivary glands

      Correct Answer: Submandibular gland

      Explanation:

      At rest, most saliva is produced by the submandibular gland (65%). When stimulated by the autonomic nervous system, about 50% of saliva is produced by the parotid gland with only 30% produced by the submandibular gland.

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      16.5
      Seconds
  • Question 31 - A 66-year-old male is brought to your clinic by his wife with the...

    Incorrect

    • A 66-year-old male is brought to your clinic by his wife with the complaint of increasing confusion and disorientation over the past three days, along with decreased urination. She reports that he has been complaining of increasing pain in his back and ribs over the past three months.

      On examination, the patient looks anaemic, is not oriented in time, place and person and has tenderness on palpation of the lumbar spine and the 10th, 11th and 12th ribs.

      Blood tests show anaemia which is normocytic, normochromic, raised urea and creatinine and hypercalcemia.

      Which one of the following diagnoses is most likely in this case?

      Your Answer: Metastatic prostate cancer

      Correct Answer: Multiple myeloma

      Explanation:

      Multiple myeloma is a clonal abnormality affecting plasma cells in which there is an overproduction of functionless immunoglobulins. The most common patient complaint is bone pain, especially in the back and ribs. Anaemia and renal failure are common, along with hypercalcemia. Hypercalcemia may lead to an altered mental status, as in this case.

      Chronic lymphocytic leukaemia occurs due to the overproduction of lymphocytes, usually B cells. CLL may present with an asymptomatic elevation of B cells. Patients are generally more than 50 years old and present with non-specific fatigue and weight loss symptoms.

      There is no history of alcohol abuse in this case. Furthermore, patients with a history of alcohol abuse may have signs of liver failure, which are not present here.

      Metastatic prostate cancer would most often cause lower backache as it metastasises first to the lumbar spine via the vertebral venous plexus.

      A patient with Vitamin B12 deficiency would have anaemia, megaloblastic, hypersegmented neutrophils, and signs of peripheral neuropathy.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      9.8
      Seconds
  • Question 32 - Approximately what proportion of lymphocytes are B-cells: ...

    Incorrect

    • Approximately what proportion of lymphocytes are B-cells:

      Your Answer: 0.05

      Correct Answer: 0.2

      Explanation:

      B-cells (20% of lymphocytes) mature in the bone marrow and circulate in the peripheral blood until they undergo recognition of antigen. B-cell immunoglobulin molecules synthesised in the cell are exported and bound to the surface membrane to become the B-cell receptor (BCR) which can recognise and bind to a specific antigen (either free or presented by APCs). The BCR is also important for antigen internalisation, processing and presentation to T helper cells. Most antibody responses require help from antigen-specific T helper cells (although some antigens such as polysaccharide can lead to T-cell independent B-cell antibody production). When the B-cell is activated, the receptor itself is secreted as free soluble immunoglobulin and the B-cell matures into a memory B-cell or a plasma cell (a B-cell in its high-rate immunoglobulin secreting state). Plasma cells are non-motile and are found predominantly in the bone marrow or spleen. Most plasma cells are short-lived (1 – 2 weeks) but some may survive much longer. A proportion of B-cells persist as memory cells, whose increased number and rapid response underlies the augmented secondary response of the adaptive immune system.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      68.4
      Seconds
  • Question 33 - A 35-year-old man suffers an open fracture of his forearm. The nerve that...

    Incorrect

    • A 35-year-old man suffers an open fracture of his forearm. The nerve that innervates the pronator quadratus muscle is damaged as a consequence of this injury.
      Which of the following nerves has been damaged in this case? Select ONE answer only.

      Your Answer: The ulnar nerve

      Correct Answer: The anterior interosseous nerve

      Explanation:

      Pronator quadratus is a small, square-shaped muscle that lies in the anterior compartment of the forearm. It arises from the distal fourth of the anterior surface of the ulna and inserts into the distal fourth of the anterior surface of the radius.
      Pronator quadratus is innervated by the anterior interosseous nerve. It receives its blood supply from the anterior interosseous artery, which is a branch of the common interosseous artery, which in turn is a branch of the ulnar artery.
      The main action of pronator quadratus is to assist pronator teres with pronation of the forearm. The deep fibres bind the radius and ulna together.
      The pronator quadratus muscle highlighted in blue (adapted from Gray’s Anatomy)

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      20.3
      Seconds
  • Question 34 - A 20-year-old asthmatic patient's symptoms is deteriorating and patient is moved to the...

    Incorrect

    • A 20-year-old asthmatic patient's symptoms is deteriorating and patient is moved to the resuscitation area of the Emergency Department. A loading dose of IV aminophylline is administered and her symptoms begin to improve. You are asked to check her theophylline levels after an appropriate time period.

      How long should you wait before taking her blood sample be taken?

      Your Answer: 24 hours

      Correct Answer: 4-6 hours

      Explanation:

      Plasma theophylline concentration is usually measured five days after starting oral treatment and three days after each dose adjustment.

      A blood sample to check theophylline concentration should usually be taken after 4-6 hours if an IV dose of aminophylline was given.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
      16.4
      Seconds
  • Question 35 - Which of the following best describes digoxin: ...

    Incorrect

    • Which of the following best describes digoxin:

      Your Answer: A negative inotrope and negative chronotrope

      Correct Answer: A positive inotrope and negative chronotrope

      Explanation:

      Digoxin is a cardiac glycoside used in the treatment of atrial fibrillation and flutter, and congestive cardiac failure. It acts by inhibiting the membrane Na/K ATPase in cardiac myocytes. This raises intracellular sodium concentration and increases intracellular calcium availability indirectly via Na/Ca exchange. The increase in intracellular calcium levels causes an increases the force of myocardial contraction (positive inotrope), and slows the heart rate (negative chronotrope).

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      5.9
      Seconds
  • Question 36 - A 73-year-old woman arrives at the emergency department 48 hours after being discharged from...

    Incorrect

    • A 73-year-old woman arrives at the emergency department 48 hours after being discharged from the hospital after a two-week stay for sepsis treatment. She has fever, productive cough with thick green sputum, and shortness of breath. An X-ray shows left lower lobe pneumonia. Which of the bacteria listed below is more likely to be the causative agent:

      Your Answer: Streptococcus pneumoniae

      Correct Answer: Pseudomonas aeruginosa

      Explanation:

      Hospital-acquired pneumonia (HAP), or nosocomial pneumonia, is a lower respiratory infection that was not incubating at the time of hospital admission and that presents clinically 2 or more days after hospitalization. Pneumonia that presents sooner should be regarded as community­ acquired pneumonia. VAP refers to nosocomial pneumonia that develops among patients on ventilators. Ventilator-associated pneumonia (VAP) is defined as pneumonia that presents more than 48 hours after endotracheal intubation.

      Common bacteria involved in hospital-acquired pneumonia (HAP) include the following [10] :
      Pseudomonas Aeruginosa
      Staphylococcus aureus, including methicillin-susceptible S aureus (MSSA) and methicillin-resistant S aureus (MRSA)
      Klebsiella pneumoniae
      Escherichia coli

    • This question is part of the following fields:

      • Infections
      • Microbiology
      4.5
      Seconds
  • Question 37 - Coagulative necrosis is typically seen in which of the following: ...

    Incorrect

    • Coagulative necrosis is typically seen in which of the following:

      Your Answer: Tuberculosis

      Correct Answer: Myocardial infarction

      Explanation:

      Coagulative necrosis is the most common form of necrosis characterised by the loss of cell nuclei, but with general preservation of the underlying architecture. Dead tissue is macroscopically pale and firm. This is the classic pattern seen in myocardial infarction.Liquefactive necrosis leads to complete loss of cellular structure and conversion into a soft, semi-solid mass. This is typically seen in the brain following cerebral infarction.Caseous necrosis is most commonly seen in tuberculosis. Histologically, the complete loss of normal tissue architecture is replaced by amorphous, granular and eosinophilic tissue with a variable amount of fat and an appearance reminiscent of cottage cheese.Gangrenous necrosis is necrosis with putrefaction of tissues due to exposure to air (dry gangrene) or infection (wet gangrene).

    • This question is part of the following fields:

      • Inflammatory Responses
      • Pathology
      4
      Seconds
  • Question 38 - Which of the following clotting factors is NOT vitamin K-dependent: ...

    Incorrect

    • Which of the following clotting factors is NOT vitamin K-dependent:

      Your Answer: II

      Correct Answer: V

      Explanation:

      Fat-soluble vitamin K is obtained from green vegetables and bacterial synthesis in the gut. Deficiency may present in the newborn (haemorrhagic disease of the newborn) or in later life. Deficiency may be caused by an inadequate diet, malabsorption or inhibition of vitamin K by drugs such as warfarin. The activity of factors II, VII, IX and X are vitamin K dependent as well as that of protein C and protein S. Both PT and APTT are prolonged.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      3.3
      Seconds
  • Question 39 - Which of the following organelles form lysosomes? ...

    Correct

    • Which of the following organelles form lysosomes?

      Your Answer: The Golgi apparatus

      Explanation:

      Lysosomes are formed by the Golgi apparatus or the endoplasmic reticulum. Lysosome releases its enzymes and digests the cell when the cell dies.

    • This question is part of the following fields:

      • Basic Cellular Physiology
      • Physiology
      17
      Seconds
  • Question 40 - If a lesion is observed in Broca's area, which function is expected to...

    Incorrect

    • If a lesion is observed in Broca's area, which function is expected to become affected?

      Your Answer: Comprehension of written language

      Correct Answer: Formation of words

      Explanation:

      The primary functions of the Broca area are both language production and comprehension. While the exact role in the production is still unclear, many believe that it directly impacts the motor movements to allow for speech. Although originally thought to only aid in speech production, lesions in the area can rarely be related to impairments in the comprehension of language. Different regions of the Broca area specialize in various aspects of comprehension. The anterior portion helps with semantics, or word meaning, while the posterior is associated with phonology, or how words sound. The Broca area is also necessary for language repetition, gesture production, sentence grammar and fluidity, and the interpretation of others’ actions.

      Broca’s aphasia is a non-fluent aphasia in which the output of spontaneous speech is markedly diminished and there is a loss of normal grammatical structure. Specifically, small linking words, conjunctions, such as and, or, and but, and the use of prepositions are lost. Patients may exhibit interjectional speech where there is a long latency, and the words that are expressed are produced as if under pressure. The ability to repeat phrases is also impaired in patients with Broca’s aphasia. Despite these impairments, the words that are produced are often intelligible and contextually correct. In pure Broca’s aphasia, comprehension is intact.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      4
      Seconds
  • Question 41 - Which of these immunoglobulin molecules can cross the placenta? ...

    Incorrect

    • Which of these immunoglobulin molecules can cross the placenta?

      Your Answer: IgM and IgG

      Correct Answer: IgG

      Explanation:

      An important mechanism that provides protection to the foetus is placental transfer of maternal IgG antibodies while his/her humoral response is inefficient. The only antibody class that significantly crosses the human placenta is IgG.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      18.4
      Seconds
  • Question 42 - Regarding co-amoxiclav, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding co-amoxiclav, which of the following statements is INCORRECT:

      Your Answer: The most common side effects of co-amoxiclav are gastrointestinal upset and rashes.

      Correct Answer: Clavulanic acid acts to inhibit cross-linking of bacterial peptidoglycan polymers.

      Explanation:

      Co-amoxiclav consists of amoxicillin with the beta-lactamase inhibitor clavulanic acid. Clavulanic acid itself has no significant antibacterial activity but, by inactivating beta-lactamases, it makes the combination active against beta-lactamase-producing bacteria that are resistant to amoxicillin.The most common adverse effects of co-amoxiclav include nausea, vomiting, skin rash and diarrhoea. Pseudomembranous colitis should be considered if a person develops severe diarrhoea during or after treatment with co-amoxiclav. Cholestatic jaundice can occur either during or shortly after the use of co-amoxiclav. An epidemiological study has shown that the risk of acute liver toxicity was about 6 times greater with co-amoxiclav than with amoxicillin. Cholestatic jaundice is more common in patients above the age of 65 years and in men; these reactions have only rarely been reported in children. Jaundice is usually self-limiting and very rarely fatal.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      8.2
      Seconds
  • Question 43 - Which of the following is NOT a typical effect caused by adrenaline: ...

    Incorrect

    • Which of the following is NOT a typical effect caused by adrenaline:

      Your Answer: Increased glycolysis

      Correct Answer: Bronchoconstriction

      Explanation:

      Actions of adrenaline:
      Cardiovascular system
      – Increased rate and force of cardiac contraction
      – Vasoconstriction of vessels in skin, mucous membranes and splanchnic bed
      – Vasodilation of skeletal muscle vessels
      – Increased cardiac output and blood pressure
      Respiratory system
      – Bronchodilation
      – Increased ventilation rate
      Gastrointestinal system
      – Smooth muscle relaxation
      – Contraction of sphincters
      – Metabolism
      – Decreased insulin release
      – Increased glucagon release
      – Increased thermogenesis
      – Increased glycolysis
      – Increased lipolysis
      Eye
      – Pupillary dilation

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      18.1
      Seconds
  • Question 44 - A patient with a diagnosis of HIV presents with a fever, sore throat,...

    Incorrect

    • A patient with a diagnosis of HIV presents with a fever, sore throat, and general malaise and you are concerned the patient may have an AIDS defining illness.

      Which one of these, according to the CDC definition, would mean a patient infected with HIV has AIDS?

      Your Answer: CD8 T-cell count of less than 200 cells/mm 3

      Correct Answer: CD4 T-cell percentage of total lymphocytes of less than 15%

      Explanation:

      According to the CDC definition, a patient co-infected with HIV can be diagnosed with AIDS if he or she has:
      A CD4 T-cell count of less than 200 cells/mm3 or;
      A CD4 T-cell percentage of total lymphocytes of less than 15% or;
      An AIDS defining infection

      A Streptococcal throat infection is not an AIDS defining infection.

      A normal CD4 count ranges from 500-1000 cells/mm3. A CD4 (not CD8) count of less than 200 cells/mm3 is AIDS defining.

      The CD4 count can vary from day to day and depending upon the time that the blood test is taken. It can also be affected by the presence of other infections or illnesses. Treatment with anti-retroviral therapy should be considered at CD4 count of less than 350 cells/mm3.

      Serum concentrations of the p24 antigen (the viral protein that makes up most of the core of the HIV) are usually high in the first few weeks after human immunodeficiency virus (HIV) infection and testing for p24 antigen is therefore a useful way of diagnosing very early infection.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      4.9
      Seconds
  • Question 45 - For which of the following is micelle formation necessary to facilitate intestinal absorption?...

    Incorrect

    • For which of the following is micelle formation necessary to facilitate intestinal absorption?

      Your Answer: Bile acids

      Correct Answer: Vitamin D

      Explanation:

      The arrangement of micelles is such that hydrophobic lipid molecules lie in the centre, surrounded by hydrophilic bile acids that are arranged in the outer region. This arrangement allows the entry of micelles into the aqueous layers surrounding the microvilli. As a result, the products of fat digestion (fatty acids and monoglycerides), cholesterol and fat-soluble vitamins (such as vitamin D) can then diffuse passively into the enterocytes. The bile salts are left within the lumen of the gut where they are reabsorbed from the ileum or excreted in faeces.

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      11.1
      Seconds
  • Question 46 - Regarding benzylpenicillin, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding benzylpenicillin, which of the following statements is CORRECT:

      Your Answer: Benzylpenicillin is first line for pneumococcal meningitis.

      Correct Answer: If meningococcal disease is suspected, benzylpenicillin should be given before transfer to hospital.

      Explanation:

      Benzylpenicillin (although inactivated by bacterial beta-lactamases) is effective for many streptococcal (including pneumococcal), gonococcal, and meningococcal infections and also for anthrax, diphtheria, gas gangrene, leptospirosis, and treatment of Lyme disease. If meningococcal disease (meningitis with non-blanching rash or meningococcal septicaemia) is suspected, benzylpenicillin should be given before transfer to hospital, so long as this does not delay the transfer; benzylpenicillin is no longer the drug of first choice for pneumococcal meningitis. Although benzylpenicillin is effective in the treatment of tetanus, metronidazole is preferred. Benzylpenicillin is inactivated by gastric acid and absorption from the gastrointestinal tract is poor and therefore it must be given by injection.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      15.9
      Seconds
  • Question 47 - Which of the following is NOT a typical clinical feature of diabetic ketoacidosis:...

    Incorrect

    • Which of the following is NOT a typical clinical feature of diabetic ketoacidosis:

      Your Answer: Tachcyardia

      Correct Answer: Cheyne–Stokes respiration

      Explanation:

      Clinical features of DKA:
      Symptoms: Polyuria, polydipsia, thirst, lethargy, weight loss, nausea, vomiting, anorexia, abdominal pain, dehydration, headache, altered mental state
      Signs: Dry mucous membranes, ketotic breath, tachycardia, hypotension, Kussmaul breathing, focal signs of precipitant e.g. infection

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      13.7
      Seconds
  • Question 48 - Which of the following bacteria is a rod-shaped, oxidase-positive, opportunistic gram-negative bacteria that...

    Correct

    • Which of the following bacteria is a rod-shaped, oxidase-positive, opportunistic gram-negative bacteria that can cause a catheter-related urinary tract infection (UTI)?

      Your Answer: Pseudomonas aeruginosa

      Explanation:

      Listeria monocytogenes is a gram-positive bacteria that does not produce spores.

      Staphylococcus aureus is a gram-positive bacteria, while Candida albicans is a gram-positive yeast with a single bud.

      Among the choices, gram-negative bacteria include only Klebsiella pneumoniae and Pseudomonas aeruginosa.

      Pseudomonas aeruginosa is an oxidase-positive bacterium, while Klebsiella pneumoniae is an oxidase-negative bacterium.

      P. aeruginosa can cause urinary tract infections (UTIs) and is spread through poor hygiene or contaminated medical equipment or devices, such as catheters that haven’t been fully sterilized.

    • This question is part of the following fields:

      • Infections
      • Microbiology
      47.7
      Seconds
  • Question 49 - A 4-year old boy is taken to the emergency room after a sudden...

    Incorrect

    • A 4-year old boy is taken to the emergency room after a sudden onset of coughing and wheezing. Further investigation reveals that he was drawing quietly in his room, when suddenly, he became anxious and started coughing. The parents also noted that the eraser on top of the pencil was missing.

      A plain radiographic chest imaging is conducted, and confirmed foreign body aspiration.

      Which of the following areas in the tracheobronchial tree is the most probable location of the aspirated eraser?

      Your Answer: Laryngotracheal junction

      Correct Answer: Right main bronchus

      Explanation:

      In foreign body aspiration, the foreign body is more likely to enter the right main bronchus because it is shorter, wider and more vertical than the left main bronchus. In a patient who is standing or sitting, the foreign body tends to become lodged in the posterobasal segment of the inferior lobe of the right lung.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      15.8
      Seconds
  • Question 50 - Which of the following statements is correct with regards to heparin-induced thrombocytopaenia (HIT)?...

    Incorrect

    • Which of the following statements is correct with regards to heparin-induced thrombocytopaenia (HIT)?

      Your Answer: HIT only occurs with unfractionated heparin.

      Correct Answer: HIT typically develops 5-10 days after starting heparin.

      Explanation:

      Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder caused by antibodies that recognize complexes of platelet factor 4 (PF4) and heparin. HIT is frequently considered in the differential diagnosis of thrombocytopenia occurring in patients on heparin therapy. HIT is a challenging diagnosis because of routine heparin use in hospitalized patients, the common occurrence of thrombocytopenia. The process of heparin dependent IgG antibodies binding to heparin/platelet factor 4 complexes activates platelets and produces a hypercoagulable state. This syndrome typically develops 5-10 days (range 4-15 days) after heparin is commenced. It can occur with unfractionated heparin, low molecular weight heparin, or, rarely, fondaparinux. The diagnosis of HIT requires the combination of a compatible clinical picture and laboratory confirmation of the presence of heparin dependent platelet activating HIT antibodies. Discontinuation of heparin alone or initiation of a vitamin K antagonist alone like warfarin, is not sufficient to stop the development of thrombosis in patients with acute HIT. If there is moderate clinical suspicion for HIT, all sources of heparin must be discontinued and there must be consideration of anticoagulant treatment with a non-heparin drug.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      5.1
      Seconds
  • Question 51 - Which of the following statements is correct with regards to Klebsiella spp? ...

    Incorrect

    • Which of the following statements is correct with regards to Klebsiella spp?

      Your Answer: They are spiral-shaped.

      Correct Answer: They are typically associated with nosocomial infection.

      Explanation:

      Klebsiella is a type of bacteria commonly found in nature. In humans, the bacteria are often present in parts of the digestive tract and respiratory flora, where they do not generally cause problems. They are anaerobic Gram-negative rods. They are usually opportunistic pathogens which cause nosocomial infections, the most common ones being pneumonia and UTI.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      8.3
      Seconds
  • Question 52 - You examine an elderly man who is experiencing chest pain. He doesn't recall...

    Incorrect

    • You examine an elderly man who is experiencing chest pain. He doesn't recall all of his medications, but he does know that he takes a diuretic.

      The enzyme carbonic anhydrase is inhibited by which of the following diuretics?

      Your Answer: Spironolactone

      Correct Answer: Acetazolamide

      Explanation:

      Acetazolamide is a non-competitive, reversible inhibitor of carbonic anhydrase found in the cytosol of cells and on the brush border of the proximal convoluted tubule. Bicarbonate and hydrogen ions are converted to carbonic acid by carbonic anhydrase, which then converts carbonic acid to carbon dioxide and water. As a result, acetazolamide reduces the availability of hydrogen ions, causing sodium and bicarbonate ions to accumulate in the renal tubule, resulting in diuresis.
      The mechanism of action of the various types of diuretics is summarised below:

      1) Loop diuretics, e.g. furosemide, bumetanide
      Act on the Na.K.2Cl co-transporters in the ascending loop of Henlé to inhibit sodium, chloride and potassium reabsorption.

      2) Thiazide diuretics, e.g. Bendroflumethiazide, hydrochlorothiazide
      Act on the Na.Cl co-transporter in the distal convoluted tubule to inhibit sodium and chloride reabsorption.

      3) Osmotic diuretics, e.g. mannitol
      Increases the osmolality of the glomerular filtrate and tubular fluid, increasing urinary volume by an osmotic effect.

      4) Aldosterone antagonists, e.g. spironolactone
      Acts in the distal convoluted tubule as a competitive aldosterone antagonist resulting in inhibition of sodium reabsorption and increasing potassium reabsorption.

      5) Carbonic anhydrase inhibitors, e.g. acetazolamide
      Inhibit the enzyme carbonic anhydrase preventing the conversion of bicarbonate and hydrogen ions into carbonic acid.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      14.2
      Seconds
  • Question 53 - A 22 year old professional athlete sustains an inversion injury to her left...

    Incorrect

    • A 22 year old professional athlete sustains an inversion injury to her left ankle during the 800m. Which of the following ligaments is most likely injured:

      Your Answer: Spring ligament

      Correct Answer: Anterior talofibular ligament

      Explanation:

      Inversion injuries at the ankle in plantarflexion (such as when wearing high heels) are common, and typically result in damage to the lateral collateral ligament of the ankle, made up of the anterior talofibular, the calcaneofibular and the posterior talofibular ligaments. The anterior talofibular and the calcaneofibular ligaments are most commonly injured, and the posterior talofibular ligament rarely. The spring ligament supports the head of the talus, the deltoid ligament supports the medial aspect of the ankle joint, and the long and short plantar ligaments are involved in maintaining the lateral longitudinal arch of the foot.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      15.5
      Seconds
  • Question 54 - Identify the type of graph described below:

    This graph is a useful tool for...

    Incorrect

    • Identify the type of graph described below:

      This graph is a useful tool for evaluating the performance of diagnostic tests and more generally for evaluating the accuracy of a statistical model (e.g., logistic regression, linear discriminant analysis) that classifies subjects into 1 of 2 categories, diseased or non diseased. The closer the graph is to the upper left corner, which represents 100% sensitivity and 100% specificity, the more accurate the diagnostic test.

      Your Answer: Forest plot

      Correct Answer: ROC curve

      Explanation:

      Receiver-operating characteristic (ROC) analysis was originally developed during World War II to analyse classification accuracy in differentiating signal from noise in radar detection. Recently, the methodology has been adapted to several clinical areas heavily dependent on screening and diagnostic tests, in particular, laboratory testing, epidemiology, radiology, and bioinformatics. ROC analysis is a useful tool for evaluating the performance of diagnostic tests and more generally for evaluating the accuracy of a statistical model (e.g., logistic regression, linear discriminant analysis) that classifies subjects into 1 of 2 categories, diseased or non diseased. Its function as a simple graphical tool for displaying the accuracy of a medical diagnostic test is one of the most well-known applications of ROC curve analysis.

      The closer the ROC curve is to the upper left corner, which has 100% sensitivity and 100% specificity, the higher the overall accuracy of the diagnostic test.

    • This question is part of the following fields:

      • Evidence Based Medicine
      9.1
      Seconds
  • Question 55 - Campylobacter jejuni is primarily spread via which of the following routes: ...

    Incorrect

    • Campylobacter jejuni is primarily spread via which of the following routes:

      Your Answer: Direct contact

      Correct Answer: Faecal-oral route

      Explanation:

      Campylobacter spp. are a common cause of acute infective gastroenteritis, particularly in children, with Campylobacter jejuni responsible for 90% of Campylobacter gastroenteritis. Infection typically follows ingestion of contaminated meat (most frequently undercooked poultry), unpasteurised milk or contaminated water, following which the microorganism invades and colonises the mucosa of the small intestine.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      12.1
      Seconds
  • Question 56 - Fatigue, dizziness upon standing, muscle weakness, weight loss, nausea, and sweating are all symptoms...

    Incorrect

    • Fatigue, dizziness upon standing, muscle weakness, weight loss, nausea, and sweating are all symptoms that a patient may experience in Addison's disease.

      Which of the following claims about Addison's disease is correct?

      Your Answer: Congenital adrenal hyperplasia is the commonest cause

      Correct Answer: ACTH levels are elevated in primary insufficiency

      Explanation:

      The adrenal glands produce too little steroid hormones, which causes Addison’s disease. The production of glucocorticoids, mineralocorticoids, and sex steroids are all altered. The most prevalent cause is autoimmune adrenalitis, which accounts for 70-80 percent of cases.

      It affects more women than males and occurs most frequently between the ages of 30 and 50.

      The following are some of the clinical signs and symptoms of Addison’s disease:

      Weakness and sluggishness
      Hypotension is a condition in which the blood pressure (notably orthostatic hypotension)
      Vomiting and nausea
      Loss of weight
      Axillary and pubic hair loss
      Depression
      Hyperpigmentation is a condition in which a person’s (palmar creases, buccal mucosa and exposed areas more commonly affected)
      The following are the classic biochemical hallmarks of Addison’s disease:
      Hyponatraemia
      Hyperkalaemia
      Hypercalcaemia
      Hypoglycaemia
      Acidosis metabolica
      When ACTH levels are combined with cortisol levels, it is possible to distinguish between primary and secondary adrenal insufficiency:
      In primary insufficiency, levels rise.
      In secondary insufficiency, levels are low or low normal.

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      4.5
      Seconds
  • Question 57 - An analytical study is conducted to compare the risk of stroke between Ticagrelor...

    Incorrect

    • An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:

      No. of patients who took Ticagrelor: 300
      No. of patients who took Ticagrelor and suffered a stroke: 30

      No. of patients who took Warfarin: 500
      No. of patients who took Warfarin and suffered a stroke: 20

      Compute for the risk ratio of a stroke.

      Your Answer: 0.06

      Correct Answer: 2.5

      Explanation:

      Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.

      RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).

      RR = ART/ARC
      RR = (30/300) / (20/500)
      RR = 2.5

      Recall that:

      If RR < 1, then the intervention reduces the risk of the outcome.
      If RR = 1, then the treatment has no effect on the outcome.
      If RR > 1, then the intervention increases the risk of the outcome.

    • This question is part of the following fields:

      • Evidence Based Medicine
      10.9
      Seconds
  • Question 58 - A 38-year-old woman is investigated for Addison's disease. She had low blood pressure,...

    Correct

    • A 38-year-old woman is investigated for Addison's disease. She had low blood pressure, weakness, weight loss, and skin discoloration. An adrenocorticotropic hormone (ACTH) stimulation test is scheduled as part of her treatment.

      Which of the following statements about ACTH is correct?

      Your Answer: It is released in response to the release of CRH

      Explanation:

      The anterior pituitary gland produces and secretes a peptide hormone called adrenocorticotropic hormone (ACTH) (adenohypophysis). It is secreted in response to the hypothalamus’s secretion of the hormone corticotropin-releasing hormone (CRH).

      ACTH promotes cortisol secretion via binding to cell surface ACTH receptors in the zona fasciculata of the adrenal cortex.

      ACTH also promotes the production of beta-endorphin, which is a precursor to melanocyte-releasing hormone (MRH).

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      26.2
      Seconds
  • Question 59 - A 35-year-old woman has complaints of nausea, abdominal pain and dark urine. On...

    Incorrect

    • A 35-year-old woman has complaints of nausea, abdominal pain and dark urine. On examination, you notice she has jaundice. She tells you she recently started a new medication.

      Which drug is NOT likely to cause cholestatic jaundice out of the following?

      Your Answer: Nitrofurantoin

      Correct Answer: Isoniazid

      Explanation:

      Isoniazid is an antibiotic used in the treatment of tuberculosis. It can cause acute, dose-dependent, hepatitis but is not a recognised cause of cholestatic jaundice.

      The drugs that cause cholestatic jaundice are the following:
      1. Nitrofurantoin
      2. Erythromycin
      3. Cephalosporins
      4. Verapamil
      5. NSAIDs
      6. ACE inhibitors
      7. Tricyclic antidepressants
      8. Phenytoin
      9. Azathioprine
      10. Carbamazepine
      11. Oral contraceptive pills
      12. Diazepam
      13. Ketoconazole
      14. Tamoxifen

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      13.5
      Seconds
  • Question 60 - Herpes simplex virus is transmitted most commonly through which of the following routes:...

    Incorrect

    • Herpes simplex virus is transmitted most commonly through which of the following routes:

      Your Answer: Airborne spread

      Correct Answer: Direct contact spread

      Explanation:

      Herpes simplex virus is the most common cause of infective encephalitis and has a predilection for the temporal lobes. Herpes simplex is transmitted through direct contact. It invades skin locally producing skin vesicles by its cytolytic activity.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      28.7
      Seconds
  • Question 61 - Which of the following ABO blood groups is the universal recipient: ...

    Incorrect

    • Which of the following ABO blood groups is the universal recipient:

      Your Answer: None of the above

      Correct Answer: AB

      Explanation:

      Blood group AB has both A and B antigens but no antibodies and thus is the universal recipient.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      22.6
      Seconds
  • Question 62 - A 32-year-old man is dehydrated as he presents with severe vomiting and diarrhoea....

    Incorrect

    • A 32-year-old man is dehydrated as he presents with severe vomiting and diarrhoea. He urgently requires resuscitation with intravenous fluid administration. He is also administered metoclopramide.

      Which of the following is the true mechanism of action of metoclopramide?

      Your Answer: 5-HT3 receptor agonism

      Correct Answer: Dopamine receptor antagonism

      Explanation:

      Metoclopramide is used to treat nausea and vomiting. It works by blocking the central and peripheral D2 (dopamine 2) receptors in the medullary chemoreceptor trigger zone in the vomiting centre (area postrema). It decreases the sensitivity of the visceral sensory nerves that transmit from the GI system to the vomiting centre. Blockade of inhibitory dopamine receptors in the GI tract may allow stimulatory actions of ACh at muscarinic synapses to predominate.

      At high doses, metoclopramide also blocks type-2 serotonin receptors though the effect is much weaker.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      16.7
      Seconds
  • Question 63 - A 55-year-old woman was complaining of headaches. On examination, the patient is found...

    Correct

    • A 55-year-old woman was complaining of headaches. On examination, the patient is found to have weakness on the left side of her body and her eyes are deviated towards the right hand side. These are signs of damage to which of the following areas?

      Your Answer: Frontal lobe

      Explanation:

      Some potential symptoms of frontal lobe damage can include loss of movement, either partial or complete, on the opposite side of the body.

      In the patient’s case, it is a result of motor cortex damage on the right side since her left side of the body is affected. The conjugate eye deviation symptom towards the side of the lesion is a result of damage to the frontal eye field.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      15.2
      Seconds
  • Question 64 - In inserting a nasogastric tube, which area is least likely to be a...

    Incorrect

    • In inserting a nasogastric tube, which area is least likely to be a site of resistance when the tube goes from the nose to the stomach?

      Your Answer: In the posterior mediastinum where the oesophagus is crossed by the left main bronchus

      Correct Answer: In the posterior mediastinum where the oesophagus is crossed by the pulmonary trunk

      Explanation:

      In the posterior mediastinum where the oesophagus is crossed by the pulmonary trunk offers the least resistance when nasogastric tube is inserted from the nose to the stomach.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      31.4
      Seconds
  • Question 65 - You are reviewing a patient following a fall from a horse. You suspect...

    Incorrect

    • You are reviewing a patient following a fall from a horse. You suspect they may have an Erb's palsy as a result of a brachial plexus injury. Regarding Erb's palsy, which one of the following statements is CORRECT:

      Your Answer: Erb's palsy affects the small muscles of the hand.

      Correct Answer: Erb's palsy may result in loss of sensation of the regimental badge area.

      Explanation:

      Erb’s palsy is caused by damage to the C5 and C6 nerve roots and thus primarily involves the musculocutaneous, suprascapular and axillary nerves. It commonly result from an excessive increase in the angle between the neck and the shoulder e.g. a person thrown from a motorbike or horseback or during a difficult birth. There is loss or weakness of abduction, lateral rotation and flexion of the arm and flexion and supination of the forearm and loss of sensation on the lateral arm. A characteristic ‘Waiter’s tip’ deformity may be present where the limb hangs limply by the side, medially rotated by the unopposed action of pectoralis major with the forearm pronated due to paralysis of the biceps brachii.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      6.4
      Seconds
  • Question 66 - Which of the following is NOT an adverse effect associated with warfarin therapy:...

    Incorrect

    • Which of the following is NOT an adverse effect associated with warfarin therapy:

      Your Answer: Pancreatitis

      Correct Answer: Neutropenia

      Explanation:

      Adverse effects of warfarin:
      The most common adverse effect of warfarin is bleeding

      Other common adverse effects of warfarin include nausea, vomiting, diarrhoea, jaundice, hepatic dysfunction, pancreatitis, pyrexia, alopecia, purpura, and rash

      Skin necrosis is a rare but serious adverse effect of warfarin; treatment with warfarin should be stopped if warfarin related skin necrosis is suspected

      Calciphylaxis is a rare, but a very serious condition that causes vascular calcification and cutaneous necrosis

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      9.7
      Seconds
  • Question 67 - A 33-year-old heavily muscled man presents with left-sided chest pain. After taking part...

    Incorrect

    • A 33-year-old heavily muscled man presents with left-sided chest pain. After taking part in a powerlifting competition, he felt a painful snap at the front of his shoulder and chest. There is also the presence of bruising and swelling over the left side of his chest. A ruptured pectoralis major muscle was suspected upon examining the injured area.

      Which of the following statements regarding the surface markings of the pectoralis major muscle is considered correct?

      Your Answer: The sternocostal head originates from the posterior surface of the sternum

      Correct Answer: It inserts into the lateral lip of the bicipital groove of the humerus

      Explanation:

      The pectoralis major is the superior most and largest muscle of the anterior chest wall. It is a thick, fan-shaped muscle that lies underneath the breast tissue and forms the anterior wall of the axilla.

      Its origin lies anterior surface of the medial half of the clavicle, the anterior surface of the sternum, the first 7 costal cartilages, the sternal end of the sixth rib, and the aponeurosis of the external oblique of the anterior abdominal wall.
      The insertion of the pectoralis major is at the lateral lip of the intertubercular sulcus of the humerus. There are 2 heads of the pectoralis major, the clavicular and the sternocostal, which reference their area of origin.
      The function of the pectoralis major is 3-fold and dependent on which heads of muscles are involved:
      – Flexion, adduction and medial rotation of the arm at the glenohumeral joint
      – Clavicular head causes flexion of the extended arm
      – Sternoclavicular head causes extension of the flexed arm

      Arterial supply of the pectoralis major, the pectoral artery, arises from the second branch of the axillary artery, the thoracoacromial trunk.

      The 2 heads of the pectoralis major have different nervous supplies. The clavicular head derives its nerve supply from the lateral pectoral nerve. The medial pectoral nerve innervates the sternocostal head. The lateral pectoral nerve arises directly from the lateral cord of the brachial plexus, and the medial pectoral nerve arises from the medial cord.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      3.4
      Seconds
  • Question 68 - Gastrin release from antral G-cells is stimulated by all but which one of...

    Incorrect

    • Gastrin release from antral G-cells is stimulated by all but which one of the following:

      Your Answer: Small peptides and amino acids in chyme

      Correct Answer: Secretin

      Explanation:

      Gastrin secretion is stimulated by:
      The presence of small peptides and amino acids in chyme
      Gastric distension
      Vagal stimulation directly via acetylcholine and indirectly via gastrin-releasing peptide (GRP)
      Raised gastric pH

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      5.9
      Seconds
  • Question 69 - Regarding haemoglobin, which of the following statements is INCORRECT: ...

    Correct

    • Regarding haemoglobin, which of the following statements is INCORRECT:

      Your Answer: Haemoglobin synthesis occurs in mature erythrocytes.

      Explanation:

      Haemoglobin is composed of four polypeptide globin chains each with its own iron containing haem molecule. Haem synthesis occurs largely in the mitochondria by a series of biochemical reactions commencing with the condensation of glycine and succinyl coenzyme A under the action of the key rate-limiting enzyme delta-aminolevulinic acid (ALA) synthase. The globin chains are synthesised by ribosomes in the cytosol. Haemoglobin synthesis only occurs in immature red blood cells.
      There are three types of haemoglobin in normal adult blood: haemoglobin A, A2 and F:
      – Normal adult haemoglobin (HbA) makes up about 96 – 98 % of total adult haemoglobin, and consists of two alpha (α) and two beta (β) globin chains. 
      – Haemoglobin A2 (HbA2), a normal variant of adult haemoglobin, makes up about 1.5 – 3.5 % of total adult haemoglobin and consists of two α and two delta (δ) globin chains.
      – Foetal haemoglobin is the main Hb in the later two-thirds of foetal life and in the newborn until approximately 12 weeks of age. Foetal haemoglobin has a higher affinity for oxygen than adult haemoglobin. 
      Red cells are destroyed by macrophages in the liver and spleen after , 120 days. The haem group is split from the haemoglobin and converted to biliverdin and then bilirubin. The iron is conserved and recycled to plasma via transferrin or stored in macrophages as ferritin and haemosiderin. An increased rate of haemoglobin breakdown results in excess bilirubin and jaundice.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      4
      Seconds
  • Question 70 - The following all cause a right shift in the oxygen dissociation curve EXCEPT...

    Correct

    • The following all cause a right shift in the oxygen dissociation curve EXCEPT for:

      Your Answer: Foetal haemoglobin

      Explanation:

      A decreased affinity of haemoglobin for oxygen (and hence increased ease of dissociation), shown by a right shift in the oxygen dissociation curve, is caused by a fall in pH, a rise in PCO2(the Bohr effect) and an increase in temperature. These changes occur in metabolically active tissues such as in exercise, and encourage oxygen release. The metabolic by-product 2,3-diphosphoglycerate (2,3 -DPG) also causes a right shift; 2, 3 -DPG may also be raised in chronic anaemia, chronic lung disease, or at high altitude. Foetal haemoglobin (HbF) binds 2, 3 -DPG less strongly than does adult haemoglobin (HbA), and so the HbF dissociation curve lies to the left of that for HbA, reflecting its higher oxygen affinity. This helps transfer oxygen from mother to foetus.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      12.8
      Seconds
  • Question 71 - A 65-year-old man complains of severe vertigo, nausea, and tinnitus. Upon presenting himself...

    Incorrect

    • A 65-year-old man complains of severe vertigo, nausea, and tinnitus. Upon presenting himself to the emergency room, it was observed that he is exhibiting ataxia, right-sided loss of pain and temperature sense on the face, and left-sided sensory loss to the body. An MRI and CT scan was ordered and the results showed that he is suffering from a right-sided stroke.

      Branches of which of the following arteries are most likely implicated in the case?

      Your Answer: Superior cerebellar artery

      Correct Answer: Basilar artery

      Explanation:

      The lateral pontine syndrome occurs due to occlusion of perforating branches of the basilar and anterior inferior cerebellar (AICA) arteries. It is also known as Marie-Foix syndrome or Marie-Foix-Alajouanine syndrome. It is considered one of the brainstem stroke syndromes of the lateral aspect of the pons.

      It is characterized by ipsilateral limb ataxia, loss of pain and temperature sensation of the face, facial weakness, hearing loss, vertigo and nystagmus, hemiplegia/hemiparesis, and loss of pain and temperature sensation.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      16.3
      Seconds
  • Question 72 - In a patient with an ongoing seizure, after what time period should treatment...

    Incorrect

    • In a patient with an ongoing seizure, after what time period should treatment be commenced?

      Your Answer: 15 minutes

      Correct Answer: 5 minutes

      Explanation:

      Immediate emergency care and treatment should be given to children, young people and adults who have prolonged or repeated convulsive seizures.
      Prolonged seizures last 5 minutes or more.
      Repeated seizures refer to 3 or more seizures in an hour.

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      6.7
      Seconds
  • Question 73 - A 18 year old student presents to ED with a headache, fever and...

    Incorrect

    • A 18 year old student presents to ED with a headache, fever and photophobia. You suspect meningitis and agree to observe your junior performing a lumbar puncture. What is the highest safest vertebral level to perform lumbar puncture in adults:

      Your Answer: L4/L5

      Correct Answer: L3/L4

      Explanation:

      In adults, the spinal cord typically ends between L1/L2 whereas the subarachnoid space extends to approximately the lower border of vertebra S2. Lumbar puncture is performed in the intervertebral space L4/L5 or L3/L4.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      7.3
      Seconds
  • Question 74 - An 80-year-old patient with a history of chronic heart failure presents to you....

    Incorrect

    • An 80-year-old patient with a history of chronic heart failure presents to you. Examination reveals widespread oedema.

      Which statement about plasma oncotic pressure (π p ) is true?

      Your Answer: Hypoalbuminaemia will increase π p

      Correct Answer: The influence of π p on fluid movement is negligible if the capillary reflection co-efficient is 0.1

      Explanation:

      Plasma oncotic pressure (πp) is typically 25-30 mmHg.

      70% of π p is generated by albumin so Hypoalbuminemia will decrease π p

      The osmotic power of albumin is enhanced by the Gibbs-Donnan effect.

      The influence of π p on fluid movement is negligible if the capillary reflection coefficient is 0.1. Another way of saying a vessel is highly permeable is saying the reflection coefficient is close to 0.

    • This question is part of the following fields:

      • Cardiovascular Physiology
      • Physiology
      6.5
      Seconds
  • Question 75 - Which of the following statements regarding the infectivity periods of these corresponding diseases...

    Incorrect

    • Which of the following statements regarding the infectivity periods of these corresponding diseases is correct?

      Your Answer: Measles is infectious for 10 days after the rash appears

      Correct Answer: Rubella is infectious until 5 days after the rash appears

      Explanation:

      Rubella can be contagious from 7 days before to 7 days after the rash appears.

      Patients with measles are contagious from 1-2 days before the onset of symptoms.

      A person with chickenpox is considered contagious beginning 1 to 2 days before rash onset until all the chickenpox lesions have crusted (scabbed).

      The infectious period of mumps is considered from 2 days before to 5 days after parotitis onset.

      Hepatitis A is highly transmissible and has an average incubation period of 28 to 30 days (range 15–50 days). The maximum infectivity is during the second half of the incubation period (i.e. while asymptomatic) and most cases are considered non-infectious after the first week of jaundice.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      13.7
      Seconds
  • Question 76 - A 23 year old student presents to ED with a widespread maculopapular rash....

    Correct

    • A 23 year old student presents to ED with a widespread maculopapular rash. She recently had a sore throat and was started on a course of antibiotics. The most likely antibiotic that she was prescribed is:

      Your Answer: Amoxicillin

      Explanation:

      Maculopapular rashes are commonly seen with ampicillin and amoxicillin. However they are not usually related to true penicillin allergy. Very often, they occur in patients with glandular fever and so, broad-spectrum penicillins should not be used blindly, for management and treatment of a sore throat. There is also an increased risk of rash in patients with acute or chronic lymphocytic leukaemia or in cytomegalovirus infection.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      4.1
      Seconds
  • Question 77 - A 45-year-old businessman returns from a trip to West Africa with headaches and...

    Incorrect

    • A 45-year-old businessman returns from a trip to West Africa with headaches and intermittent fevers. Thick and thin films are sent to the lab and a diagnosis is made of malaria. The patient is started on treatment but his condition deteriorates and he develops jaundice, renal failure and haemoglobinuria.
      Which of the following is the MOST likely causative organism? Select ONE answer only.

      Your Answer: Plasmodium ovale

      Correct Answer: Plasmodium falciparum

      Explanation:

      Malaria is an infectious disease transmitted by female of theAnophelesgenus of mosquito. It is a parasitic infection caused by the genusPlasmodium. Five species are recognized as causing disease in humans;Plasmodium falciparum,Plasmodium ovale,Plasmodium vivax,Plasmodium malariaeandPlasmodium knowlesi.
      The classic symptom of malaria is the malarial paroxysm, a cyclical occurrence of a cold phase, where the patient experiences intense chills, a hot stage, where the patient feels extremely hot and finally a sweating stage, where the fever declines and the patient sweats profusely. On examination the patient may show signs of anaemia, jaundice and have hepatosplenomegaly without evidence of lymphadenopathy.

      Plasmodium falciparum is the most serious form and is responsible for most deaths. Severe or complicated malaria is suggested by the presence of impaired consciousness, seizures, hypoglycaemia, anaemia, renal impairment, respiratory distress and spontaneous bleeding.
      Plasmodium falciparum is the most likely type in this case in view of the presentation.
      Haemoglobinuria and renal failure following treatment is suggestive of blackwater fever, which is caused byPlasmodium falciparum. An autoimmune reaction between the parasite and quinine causes haemolysis, haemoglobinuria, jaundice and renal failure. This can be fatal.
      The benign malarias: P.vivax, P. malariae and P.ovale are usually treated with chloroquine. A course of primaquine is also required in P.vivax and P.ovale infection. Artesunate is the drug treatment of choice for Plasmodium falciparum malaria. Quinine can still be used where artesunate is not available. Often combination therapy with drugs such as doxycycline or fansidar is also required.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      2.2
      Seconds
  • Question 78 - Superficial fibular nerve palsy results in which of the following clinical features: ...

    Incorrect

    • Superficial fibular nerve palsy results in which of the following clinical features:

      Your Answer: Loss of inversion of the foot

      Correct Answer: Loss of eversion of the foot

      Explanation:

      Damage to the superficial fibular nerve results in loss of eversion of the foot and loss of sensation over the lower anterolateral leg and the dorsum of the foot.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      6.6
      Seconds
  • Question 79 - A 58-year-old male has cellulitis of his left leg. Because he is allergic to...

    Incorrect

    • A 58-year-old male has cellulitis of his left leg. Because he is allergic to penicillin, you start him on erythromycin.

      What is erythromycin's mechanism of action?

      Your Answer: Inhibition of cell wall synthesis

      Correct Answer: Inhibition of protein synthesis

      Explanation:

      Bacteriostatic antibiotics include erythromycin and other macrolide antibiotics. They work by attaching to the bacterial ribosome’s 50S subunit, preventing translocation and thereby protein synthesis. Macrolide antibiotics are actively concentrated inside leukocytes and delivered to the infection site as a result.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      10.8
      Seconds
  • Question 80 - Regarding fibrinolytics, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding fibrinolytics, which of the following statements is INCORRECT:

      Your Answer: Tenecteplase has a longer half-life than alteplase allowing for bolus administration.

      Correct Answer: Fibrinolytic drugs act as thrombolytics by directly degrading the fibrin mesh and so breaking up thrombi.

      Explanation:

      Fibrinolytic drugs act as thrombolytics by activating plasminogen to form plasmin, which degrades fibrin and so breaks up thrombi.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      12.4
      Seconds
  • Question 81 - Fat necrosis is typically seen in which of the following: ...

    Incorrect

    • Fat necrosis is typically seen in which of the following:

      Your Answer: Tuberculosis

      Correct Answer: Acute pancreatitis

      Explanation:

      Fat necrosis typically occurs following either direct trauma or from enzymatic lipolysis in acute pancreatitis, where release of triglyceride elicits a rapid inflammatory response and fat is phagocytosed by neutrophils and macrophages with subsequent fibrosis.

    • This question is part of the following fields:

      • Inflammatory Responses
      • Pathology
      2.2
      Seconds
  • Question 82 - A tumour compresses the jugular foramen of a 50-year-old patient. Compression of several...

    Incorrect

    • A tumour compresses the jugular foramen of a 50-year-old patient. Compression of several nerves in the jugular foramen will result in which of the following complications?

      Your Answer: Loss of hearing

      Correct Answer: Loss of gag reflex

      Explanation:

      The glossopharyngeal nerve, which is responsible for the afferent pathway of the gag reflex, the vagus nerve, which is responsible for the efferent pathway of the gag reflex, and the spinal accessory nerve all exit the skull through the jugular foramen. These nerves are most frequently affected if the jugular foramen is compressed. As a result, the patient’s gag reflex is impaired.

      The vestibulocochlear nerve is primarily responsible for hearing. The trigeminal nerve provides sensation in the face. The facial nerve innervates the muscles of face expression (including those responsible for closing the eye). Tongue motions are controlled mostly by the hypoglossal nerve.

    • This question is part of the following fields:

      • Anatomy
      • Cranial Nerve Lesions
      6.6
      Seconds
  • Question 83 - An very unwell patient is receiving treatment in your hospital's HDU and is...

    Incorrect

    • An very unwell patient is receiving treatment in your hospital's HDU and is found to have an Escherichia coli O157 infection.

      Which one of these statements about Escherichia coli O157 is true?

      Your Answer: The incubation period is typically 6-12 hours

      Correct Answer: Haemolytic uraemic syndrome develops in approximately 6% of patients

      Explanation:

      Escherichia coli O157 is a serotype of Escherichia coli.
      The Escherichia coliO157 strain is ‘enterohaemorrhagic’ and causes severe forms of acute haemorrhagic diarrhoea. It can also cause non-haemorrhagic diarrhoea.

      Incubation period of Escherichia coli O157 is usually 3-4 days and bloody diarrhoea usually begins on the 3rd or 4th day of the infection.

      Infections with Escherichia coliO157 are more common during the warmer months than in winter.

      Haemolytic uraemic syndrome develops in approximately 6% of patients. It is commonly seen in children and in the elderly.

      Escherichia coli O157 can also cause:
      Haemorrhagic colitis
      Haemolytic uraemic syndrome
      Thrombotic thrombocytopenic purpura but not immune thrombocytopenic purpura.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      19.7
      Seconds
  • Question 84 - A clinical audit cycle comprises of 5 steps. Each of these processes are...

    Incorrect

    • A clinical audit cycle comprises of 5 steps. Each of these processes are listed below:
      Which is the correct order that these should occur?

      1. Observation of practice and collection of data
      2. Identification of the problem
      3. Implementation of change
      4. Definition of criteria and setting of standards
      5. Analysis of data and comparison of performance with the criteria and standards

      Your Answer: 3,4,2,5,1

      Correct Answer: 2,4,1,5,3

      Explanation:

      An audit assesses if a certain aspect of health care is attaining a recognized standard. This lets care providers and patients know where their service is doing well, and where there could be improvements. The aim is to achieve quality improvement and improve outcomes for patients.

      Audits are a quality improvement measure and one of the 7 pillars of clinical governance. It allows organizations to continually work toward improving quality of care by showing them where they are falling short, allows them to implement improvements, and reaudit or close the audit cycle to see if beneficial change has taken place.

      Clinical audits are a cycle with several steps:

      1. Identification of the problem
      2. Definition of criteria and setting of standards
      3. Observation of practice and collection of data
      4. Analysis of data and comparison of performance with the criteria and standards
      5. Implementation of change

    • This question is part of the following fields:

      • Evidence Based Medicine
      1.8
      Seconds
  • Question 85 - A 68-year-old man has a very fast heartbeat' and is out of breath....

    Correct

    • A 68-year-old man has a very fast heartbeat' and is out of breath. He has had a heart transplant in the past. His electrocardiogram reveals supraventricular tachycardia.

      Which of the following is the most appropriate adenosine dose for him to receive as a first dose?

      Your Answer: Adenosine 3 mg IV

      Explanation:

      A rapid IV bolus of adenosine is given, followed by a saline flush. The standard adult dose is 6 mg, followed by 12 mg if necessary, and then another 12 mg bolus every 1-2 minutes until an effect is seen.

      Patients who have had a heart transplant, on the other hand, are extremely sensitive to the effects of adenosine and should start with a lower dose of 3 mg, then 6 mg, and finally 12 mg.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      21.7
      Seconds
  • Question 86 - A patient suffers from an injury and as a consequence, is unable to...

    Incorrect

    • A patient suffers from an injury and as a consequence, is unable to externally rotate his femur when his hip is extended. You suspect a nerve injury to the obturator internus muscle. Which of the following nerves innervate the obturator internus muscle?

      Your Answer: Obturator nerve

      Correct Answer: Obturator internus nerve

      Explanation:

      The obturator internus is innervated by the obturator internus nerve (L5–S2), a branch of sacral plexus.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      4.6
      Seconds
  • Question 87 - Molecules with a molecular weight of less than which of the following are...

    Incorrect

    • Molecules with a molecular weight of less than which of the following are filtered freely at the glomerular filtration barrier:

      Your Answer: 10000 Da

      Correct Answer: 7000 Da

      Explanation:

      Molecular weight is the main factor in determining whether a substance is filtered or not – molecules < 7 kDa in molecular weight are filtered freely e.g. glucose, amino acids, urea, ions but larger molecules are increasingly restricted up to 70 kDa, above which filtration is insignificant. Negatively charged molecules are further restricted, as they are repelled by negative charges, particularly in the basement membrane. Albumin has a molecular weight of 69 kDa and is negatively charged, thus only very small amounts are filtered (and all of the filtered albumin is reabsorbed in the proximal tubule), whereas small molecules such as ions, glucose, amino acids and urea pass the filter without hindrance. This means that ultrafiltrate is virtually protein free, but otherwise has an identical composition of that of plasma. The epithelial lining of the Bowman's capsule consists of a single layer of cells called podocytes. The glomerular capillary endothelium is perforated by pores (fenestrations) which allow plasma components with a molecular weight of < 70 kDa to pass freely.

    • This question is part of the following fields:

      • Physiology
      • Renal
      18.3
      Seconds
  • Question 88 - A blood culture was performed from a sample taken from a patient. It...

    Incorrect

    • A blood culture was performed from a sample taken from a patient. It was noted that a Gram-positive coccus organism was grown.

      Among the following microorganisms, which is considered an example of a Gram-positive coccus?

      Your Answer: Salmonella enterica

      Correct Answer: Staphylococcus aureus

      Explanation:

      Bacillus cereus = Gram-positive bacillus
      Neisseria meningitidis = Gram-negative coccus
      Salmonella enterica & Escherichia coli = Gram-negative bacilli

      In Gram staining, crystal violet is a purple stain that is used to stain the bacteria first. The stained bacteria are decolorized and then stained with a red stain, which is safranin. Bacteria with thick cell walls keep the purple stain and are called Gram-positive. Thin-walled bacteria are easily decolorized so when safranin, the red stain, is placed on the organisms, they become red or Gram-negative.
      The Staphylococci that are associated with infections in humans are colonizers of various skin and mucosal surfaces. Because the carrier state is common among the human population, infections are frequently acquired when the colonizing strain gains entrance to a normally sterile site as a result of trauma or abrasion to the skin or mucosal surface.

    • This question is part of the following fields:

      • Microbiology
      • Principles Of Microbiology
      8.1
      Seconds
  • Question 89 - You want to give colchicine to a patient who has acute gout. Which...

    Correct

    • You want to give colchicine to a patient who has acute gout. Which of the following is a contraindication to the use of colchicine?

      Your Answer: Blood dyscrasias

      Explanation:

      Colchicine is used to prevent or treat gout attacks (flares). It works by reducing swelling and the development of uric acid crystals, which cause pain in the affected joint(s).

      Colchicine should be avoided by patients who have blood dyscrasias or bone marrow disorders.

    • This question is part of the following fields:

      • Musculoskeletal
      • Pharmacology
      10.9
      Seconds
  • Question 90 - Urine flow rate = 2 ml/min
    Urine concentration of creatinine = 18 mg/ml
    Plasma...

    Incorrect

    • Urine flow rate = 2 ml/min
      Urine concentration of creatinine = 18 mg/ml
      Plasma concentration of creatinine = 0.25 mg/ml

      What is the estimated glomerular filtration rate (eGFR)?

      Your Answer: 0.01 ml/min

      Correct Answer: 144 ml/min

      Explanation:

      GFR can be estimated by:
      GFR = UCr x V / PCr
      Where:
      UCr = urine concentration of creatinine
      PCr = plasma concentration of creatinine
      V = rate of urine flow

      In this case GFR = (18 x 2) / 0.25 = 144 ml/min

      Note: Creatinine is used to estimate GFR because it is an organic base naturally produced by muscle breakdown, it is freely filtered at the glomerulus, it is not reabsorbed from the nephron, it is not produced by the kidney, it is not toxic, and it doesn’t alter GFR.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      8.4
      Seconds
  • Question 91 - Regarding inhaled corticosteroids, which of the following statements is INCORRECT: ...

    Correct

    • Regarding inhaled corticosteroids, which of the following statements is INCORRECT:

      Your Answer: Lower doses of inhaled corticosteroids may be required in smokers.

      Explanation:

      Current and previous smoking reduces the effectiveness of inhaled corticosteroids and higher doses may be necessary.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory
      11.2
      Seconds
  • Question 92 - A pheochromocytoma is diagnosed in a 38-year-old female who has had episodes of...

    Incorrect

    • A pheochromocytoma is diagnosed in a 38-year-old female who has had episodes of acute sweating, palpitations, and paroxysmal hypertension.

      Which of the following is the MOST SUITABLE INITIAL TREATMENT?

      Your Answer: Surgery

      Correct Answer: Alpha-blocker

      Explanation:

      A phaeochromocytoma is a rare functional tumour that develops in the adrenal medulla from chromaffin cells. Extra-adrenal paragangliomas (extra-adrenal pheochromocytomas) are tumours that arise in the sympathetic nervous system’s ganglia and are closely connected to extra-adrenal paragangliomas (extra-adrenal pheochromocytomas). Catecholamines are secreted by these tumours, which generate a variety of symptoms and indications associated with sympathetic nervous system hyperactivity.
      Hypertension is the most prevalent presenting symptom, which can be continuous or intermittent.

      Symptoms are usually intermittent, occurring anywhere from many times a day to occasionally. The symptoms of the condition tend to grow more severe and frequent as the disease progresses.
      The ultimate therapy of choice is surgical resection, and if full resection is done without metastases, hypertension is typically cured.

      Preoperative medical treatment is critical because it lowers the risk of hypertensive crises during surgery. This is commonly accomplished by combining non-competitive alpha-blockers (such as phenoxybenzamine) with beta-blockers. To allow for blood volume expansion, alpha-blockade should be started at least 7-10 days before surgery. Beta-blockade, which helps to regulate tachycardia and some arrhythmias, can be started after this is accomplished. Hypertensive crises can be triggered if beta-blockade is started too soon.
      There should also be genetic counselling, as well as a search for and management of any linked illnesses.

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      5.4
      Seconds
  • Question 93 - A 44 year old woman is brought to ED having fallen down the...

    Incorrect

    • A 44 year old woman is brought to ED having fallen down the stairs and injured her right arm. On examination she is unable to abduct her arm normally, and has weakness of lateral rotation. She has sensory loss over the lateral aspect of her upper arm. Which of the following injuries is most likely to produce this pattern of injury:

      Your Answer: Fracture of the lateral border of the scapula

      Correct Answer: Surgical neck of humerus fracture

      Explanation:

      Damage to the axillary nerve will result in loss of abduction past about 15 degrees and weakness of lateral rotation due to paralysis of the deltoid and teres minor and loss of sensation over the regimental badge area on the upper lateral arm. The axillary nerve is most likely injured in fracture of the surgical neck of the humerus due to its course where it winds around this region together with the posterior humeral circumflex vessels.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      34.5
      Seconds
  • Question 94 - At rest, the left dome of the diaphragm normally reaches as high as...

    Incorrect

    • At rest, the left dome of the diaphragm normally reaches as high as which of the following:

      Your Answer: Fourth intercostal space

      Correct Answer: Fifth intercostal space

      Explanation:

      At rest the right dome of the diaphragm lies slightly higher than the left; this is thought to be due to the position of the liver. In normal expiration, the normal upper limits of the superior margins are the fifth rib for the right dome, the fifth intercostal space for the left dome and the xiphoid process for the central tendon.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      6.5
      Seconds
  • Question 95 - Which of the following is a clinical effect of hyperkalaemia: ...

    Incorrect

    • Which of the following is a clinical effect of hyperkalaemia:

      Your Answer: Constipation

      Correct Answer: Muscle weakness

      Explanation:

      Clinical features of hyperkalaemia may include:
      paraesthesia, muscle weakness or paralysis, cardiac conduction abnormalities and dysrhythmias.

      Clinical features of hypokalaemia may include:
      muscle weakness, muscle cramps, rhabdomyolysis and myoglobinuria, ascending paralysis resulting in respiratory failure, constipation, gut ileus with distension, anorexia, nausea and vomiting, impaired ADH action with polyuria and polydipsia, ECG changes and cardiac arrhythmias.

    • This question is part of the following fields:

      • Physiology
      • Renal
      13.6
      Seconds
  • Question 96 - A patient presents with epistaxis. She tells you that she has a rare...

    Incorrect

    • A patient presents with epistaxis. She tells you that she has a rare platelet disorder and gives you her haematology outpatient letter that contains information about it. You learn that her disorder is caused by low levels of glycoprotein IIb/IIIa.
      What is the SINGLE most likely diagnosis?

      Your Answer: Von Willebrand disease

      Correct Answer: Glanzamann’s thromboasthenia

      Explanation:

      Glanzmann’s thromboasthenia is a rare platelet disorder in which platelets contain defective or low levels of glycoprotein IIb/IIIa.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      15.9
      Seconds
  • Question 97 - A 25-year-old footballer develops pain and stiffness in his thigh. A diagnosis of...

    Incorrect

    • A 25-year-old footballer develops pain and stiffness in his thigh. A diagnosis of iliopsoas syndrome is made.
      Iliacus is innervated by which of the following nerves? Select ONE answer only.

      Your Answer: Obturator nerve

      Correct Answer: Femoral nerve

      Explanation:

      Iliacus is innervated by the femoral nerve.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      37.3
      Seconds
  • Question 98 - An ambulance transports a 37-year-old woman who is having a seizure. She is...

    Incorrect

    • An ambulance transports a 37-year-old woman who is having a seizure. She is moved to resuscitation and given a benzodiazepine dose, which quickly ends the seizure. You later learn that she has epilepsy and is usually treated with carbamazepine to control her seizures.

      What is carbamazepine's main mechanism of action?

      Your Answer: GABA receptor agonist

      Correct Answer: Sodium channel blocker

      Explanation:

      Carbamazepine is primarily used to treat epilepsy, and it is effective for both focal and generalised seizures. It is not, however, effective in the treatment of absence or myoclonic seizures. It’s also commonly used to treat neuropathic pain, as well as a second-line treatment for bipolar disorder and as a supplement for acute alcohol withdrawal.

      Carbamazepine works as a sodium channel blocker that preferentially binds to voltage-gated sodium channels in their inactive state. This prevents an action potential from firing repeatedly and continuously.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      21.8
      Seconds
  • Question 99 - Regarding fat digestion, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding fat digestion, which of the following statements is CORRECT:

      Your Answer: Fatty acids and monoglycerides in the duodenum stimulate gastric emptying.

      Correct Answer: Lipids are reesterified in the smooth endoplasmic reticulum of the enterocyte.

      Explanation:

      Fats are digested almost entirely in the small intestine and are only released from the stomach into the duodenum at the rate at which they can be digested (the presence of fatty acids and monoglycerides in the duodenum inhibits gastric emptying). In the duodenum fat is emulsified by bile acids, a process where larger lipid droplets are broken down into much smaller droplets providing a greater surface area for enzymatic digestion. Pancreatic lipase digests triglyceride into monoglycerides and free fatty acids. The products of fat digestion (fatty acids and monoglycerides), cholesterol and fat-soluble vitamins diffuse passively into the enterocytes. Once inside the epithelial cell, lipid is taken into the smooth endoplasmic reticulum where much of it is re esterified. Dietary and synthesised lipids are then incorporated into chylomicrons in the Golgi body, which are exocytosed from the basolateral membrane to enter lacteals.

    • This question is part of the following fields:

      • Gastrointestinal
      • Physiology
      12.7
      Seconds
  • Question 100 - You review a patient with urinary sepsis and decide to start her...

    Incorrect

    • You review a patient with urinary sepsis and decide to start her on gentamicin.

      Which statement about gentamicin is true?

      Your Answer: It can be used to treat Neisseria meningitidis infections

      Correct Answer: Ototoxicity is a dose-related effect

      Explanation:

      Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA, and thus prevents initiation of protein synthesis.

      Gentamicin is given by injection because it is NOT absorbed orally.

      It is excreted in the kidneys by glomerular filtration

      Gentamicin is not to be used for the treatment of Neisseria meningitidis, Neisseria gonorrhoea, or Legionella pneumophila.There is a risk of patient going into shock from lipid A endotoxin release.

      Two of its most notable side effects are hearing loss reversible nephrotoxicity and which are both dose-related and levels should be monitored in patients.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      9.4
      Seconds
  • Question 101 - A 24-year-old man goes to the emergency department with a fever, headache, and...

    Incorrect

    • A 24-year-old man goes to the emergency department with a fever, headache, and swollen parotid glands that are excruciating. You have a suspicion that it is mumps. Which of the following nerves is causing the discomfort the patient is experiencing:

      Your Answer: Zygomaticotemporal nerve

      Correct Answer: Auriculotemporal nerve

      Explanation:

      The auriculotemporal nerve is irritated by mumps, which results in significant discomfort due to inflammation and swelling of the parotid gland, as well as the stretching of its capsule. Compression caused by swallowing or chewing exacerbates pain.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      15.5
      Seconds
  • Question 102 - A patient allergic to penicillin and with marked cellulitis presents and you...

    Incorrect

    • A patient allergic to penicillin and with marked cellulitis presents and you decide to start him on erythromycin.

      Which statement about macrolide antibiotics is true?

      Your Answer: They can be used to treat meningitis

      Correct Answer: They are actively concentrated within leukocytes

      Explanation:

      Macrolide antibiotics are bacteriostatic.

      They act by binding to the 50S subunit of the bacterial ribosome inhibit protein synthesis.

      Macrolide antibiotics are actively concentrated within leukocytes, because of this, they are transported into the site of infection.

      Macrolide antibiotics are not effective in meningitis as they do not penetrate the central nervous system well.

      They are mainly against Gram-positive organisms and can be used as an alternative in patients with penicillin allergy.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      25.5
      Seconds
  • Question 103 - A 50-year-old man has recently been on antibiotics for a chest infection. He...

    Incorrect

    • A 50-year-old man has recently been on antibiotics for a chest infection. He suffers from COPD and is currently on Seretide inhalers, salbutamol, and Phyllocontin continus. Since commencing the antibiotics, he has developed nausea, vomiting and abdominal pain.

      Which of the following antibiotics has he MOST LIKELY been on for his chest infection?

      Your Answer: Co-amoxiclav

      Correct Answer: Erythromycin

      Explanation:

      Phyllocontin continues contains aminophylline, a bronchodilator used in the management of asthma and COPD.

      The index patient is exhibiting symptoms of theophylline toxicity. This may have been triggered by the antibiotic he took. Macrolide antibiotics, like erythromycin and quinolone antibiotics, like ciprofloxacin and levofloxacin, increases the plasma concentration of theophyllines and can lead to toxicity.

      Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin.
      Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
      5.9
      Seconds
  • Question 104 - You examine a 48-year-old woman's blood results and notice that her glucose level...

    Correct

    • You examine a 48-year-old woman's blood results and notice that her glucose level is elevated. When you tell her about it, she tells you that her doctor recently ran some tests and discovered that she has impaired glucose tolerance.

      Which of the following medications has not been linked to a reduction in glucose tolerance?

      Your Answer: Amlodipine

      Explanation:

      The following drugs have been linked to impaired glucose tolerance:
      Thiazide diuretics, e.g. Bendroflumethiazide
      Loop diuretics, e.g. furosemide
      Steroids, e.g. prednisolone
      Beta-blockers, e.g. atenolol

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      10.8
      Seconds
  • Question 105 - A 12-year-old boy presents to you with a history of fever. A rash...

    Incorrect

    • A 12-year-old boy presents to you with a history of fever. A rash began as small red dots on the face, scalp, torso, upper arms and legs shortly afterwards and has now progressed to small blisters and pustules. You make a diagnosis of chickenpox.

      The following complications of chickenpox is the LEAST likely.

      Your Answer: Orchitis

      Correct Answer: Bronchospasm

      Explanation:

      Chickenpox (varicella zoster) is a highly contagious airborne disease and has an incubation period of between 7-21 days. It often has a prodromal phase when there is a fever, aches and headaches, dry cough, and sore throat before onset of rash.

      Some recognized complications of chickenpox are:
      Orchitis
      Hepatitis
      Pneumonia
      Encephalitis
      Infected spots
      Otitis media
      Myocarditis
      Glomerulonephritis
      Appendicitis
      Pancreatitis

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      10.9
      Seconds
  • Question 106 - Which of the following accurately describes the extensor pollicis brevis muscle? ...

    Incorrect

    • Which of the following accurately describes the extensor pollicis brevis muscle?

      Your Answer: It extends the distal phalanx of the thumb at the metacarpophalangeal joint

      Correct Answer: It lies on the medial side of abductor pollicis longus

      Explanation:

      Extensor pollicis brevis is a short and slender muscle located in the posterior compartment of the forearm, extending from the posterior surface of radius to the proximal phalanx of thumb. It is one of the deep extensors of the forearm, together with supinator, abductor pollicis longus, extensor pollicis longus and extensor indicis muscles.

      Extensor pollicis brevis is a deep extensor of the thumb that lies deep to extensor digitorum muscle. It sits directly medial to abductor pollicis longus and posterolateral to extensor pollicis longus muscle. Just above the wrist, extensor pollicis brevis obliquely crosses the tendons of extensor carpi radialis brevis and extensor carpi radialis longus muscles.

      Extensor pollicis brevis is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).

      Extensor pollicis brevis receives its blood supply by posterior interosseous artery and perforating branches from the anterior interosseous artery, which are the branches of common interosseous artery. The common interosseous artery arises immediately below the tuberosity of radius from the ulnar artery.

      Together with extensor pollicis longus, extensor pollicis brevis is in charge of extension of the thumb in the first metacarpophalangeal joint. It also extends the thumb in the carpometacarpal joint of the thumb. This movement is important in the anatomy of the grip, as it enables letting go of an object. As it crosses the wrist, extensor pollicis brevis also participates in the extension and abduction of this joint.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      29
      Seconds
  • Question 107 - Which of the following is NOT a side effect of phenytoin: ...

    Incorrect

    • Which of the following is NOT a side effect of phenytoin:

      Your Answer: Skin rashes

      Correct Answer: Ototoxicity

      Explanation:

      Adverse effects of phenytoin include:
      Nausea and vomiting
      Drowsiness, lethargy, and loss of concentration
      Headache, dizziness, tremor, nystagmus and ataxia
      Gum enlargement or overgrowth
      Coarsening of facial features, acne and hirsutism
      Skin rashes
      Blood disorders

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      9.8
      Seconds
  • Question 108 - The hypothalamus produces antidiuretic hormone (ADH), also known as vasopressin, which is a...

    Incorrect

    • The hypothalamus produces antidiuretic hormone (ADH), also known as vasopressin, which is a peptide hormone. It is important for maintaining water and electrolyte balance, as well helping control arterial pressure.

      To have an effect on blood arteries, ADH binds to which of the following receptors?

      Your Answer: AT 2 receptor

      Correct Answer: V 1 receptor

      Explanation:

      ADH, or antidiuretic hormone, is a hormone that regulates water and electrolyte balance. It is released in response to a variety of events, the most important of which are higher plasma osmolality or lower blood pressure. ADH increases plasma volume and blood pressure via acting on the kidneys and peripheral vasculature.

      It causes vasoconstriction by binding to peripheral V1 Receptors on vascular smooth muscle via the IP3 signal transduction and Rho-kinase pathways. The systemic vascular resistance and arterial pressure rise as a result. High levels of ADH appear to be required for this to have a major impact on arterial pressure, such as in hypovolaemic shock.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      11.8
      Seconds
  • Question 109 - A patient is sent in by her GP with suspected ectopic pregnancy. Tubal...

    Incorrect

    • A patient is sent in by her GP with suspected ectopic pregnancy. Tubal ectopic pregnancies occur most commonly in which part of the uterine tube:

      Your Answer: Isthmus

      Correct Answer: Ampulla

      Explanation:

      Ectopic pregnancy most commonly occurs in the ampulla (70% of cases).

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      7.3
      Seconds
  • Question 110 - Despite taking the oral contraceptive pill, a 29-year-old woman becomes pregnant. During a...

    Incorrect

    • Despite taking the oral contraceptive pill, a 29-year-old woman becomes pregnant. During a medication review, you discover that she is epileptic and that her antiepileptic therapy has recently been changed.

      Which of the following antiepileptics is most likely to impair the oral contraceptive pill's effectiveness?

      Your Answer: Levetiracetam

      Correct Answer: Carbamazepine

      Explanation:

      The metabolism of ethinyl oestradiol and progestogens has been shown to be increased by enzyme-inducing antiepileptics. The oral contraceptive pill (OCP) is less effective in preventing pregnancy as a result of this increased breakdown.

      Antiepileptic drugs that induce enzymes include:
      Carbamazepine
      Phenytoin
      Phenobarbital
      Topiramate

      Antiepileptics that do not induce enzymes are unlikely to affect contraception. Non-enzyme-inducing anticonvulsants include the following:
      Clonazepam
      Gabapentin
      Levetiracetam
      Piracetam
      Sodium valproate is a type of valproate that is used to

      Lamotrigine is an antiepileptic drug that does not cause the production of enzymes. It does, however, require special consideration, unlike other non-enzyme-inducing antiepileptics. The OCP does not appear to affect epilepsy directly, but it does appear to lower lamotrigine levels in the blood. This could result in a loss of seizure control and the occurrence of seizures.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      5.6
      Seconds
  • Question 111 - The big toe of a 59-year-old female is red, hot, and swollen. The patient is...

    Correct

    • The big toe of a 59-year-old female is red, hot, and swollen. The patient is diagnosed with acute gout. You intend to start her on a nonsteroidal anti-inflammatory medicine (NSAID). Her husband was diagnosed with a peptic ulcer, and she is apprehensive about the potential adverse effects of NSAIDs.

      Which of the following NSAIDs has the lowest chance of causing side effects?

      Your Answer: Ibuprofen

      Explanation:

      Non-steroidal anti-inflammatory medications (NSAIDs) have slight differences in anti-inflammatory activity, but there is a lot of diversity in individual response and tolerance to these treatments. Approximately 60% of patients will respond to any NSAID; those who do not respond to one may well respond to another. Pain relief begins soon after the first dose, and a full analgesic effect should be achieved within a week, whereas an anti-inflammatory effect may take up to three weeks to achieve (or to be clinically assessable). If the desired results are not reached within these time frames, another NSAID should be attempted.

      By inhibiting the enzyme cyclo-oxygenase, NSAIDs limit the generation of prostaglandins. They differ in their selectivity for inhibiting various types of cyclo-oxygenase; selective inhibition of cyclo-oxygenase-2 is linked to reduced gastrointestinal discomfort. Susceptibility to gastrointestinal effects is influenced by a number of different parameters, and an NSAID should be chosen based on the frequency of side effects.
      Ibuprofen is an anti-inflammatory, analgesic, and antipyretic propionic acid derivative. Although it has fewer side effects than other non-selective NSAIDs, its anti-inflammatory properties are less effective. For rheumatoid arthritis, daily doses of 1.6 to 2.4 g are required, and it is contraindicated for illnesses characterized by inflammation, such as acute gout.

      Because it combines strong efficacy with a low incidence of adverse effects, Naproxen is one of the top choices. It is more likely to cause negative effects than ibuprofen.
      Similar to ibuprofen, ketoprofen and diclofenac have anti-inflammatory characteristics, however they have additional negative effects.

      Indomethacin has a similar or better effect to naproxen, however it comes with a lot of side effects, such as headaches, dizziness, and gastrointestinal problems.

    • This question is part of the following fields:

      • Musculoskeletal Pharmacology
      • Pharmacology
      18.8
      Seconds
  • Question 112 - All of the following statements are correct regarding the management of acute asthma...

    Incorrect

    • All of the following statements are correct regarding the management of acute asthma in adults except:

      Your Answer: Continuous salbutamol nebulisation should be considered in patients with severe acute asthma that is poorly responsive to initial bolus dose of salbutamol.

      Correct Answer: Intravenous aminophylline has been shown to result in significant additional bronchodilation compared to standard care.

      Explanation:

      There usually isn’t any additional bronchodilation with intravenous (IV) aminophylline compared to standard care with inhaled bronchodilators and steroids. IV aminophylline may cause side effects such as arrhythmias and vomiting. However, some additional benefit may be gained in patients with near-fatal asthma or life-threatening asthma with a poor response to initial therapy (5 mg/kg loading dose over 20 minutes unless on maintenance oral therapy, then continuous infusion of 0.5 – 0.7 mg/kg/hr).

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory
      30.9
      Seconds
  • Question 113 - A 26-year-old man is involved in a motorcycle accident that results in an...

    Incorrect

    • A 26-year-old man is involved in a motorcycle accident that results in an open fracture of his tibia and fibula. The nerve that innervates peroneus tertius is damaged as a consequence of his injuries.
      Peroneus tertius receives its innervation from which of the following nerves? Select ONE answer only.

      Your Answer: Femoral nerve

      Correct Answer: Deep peroneal nerve

      Explanation:

      Peroneus brevis is innervated by the superficial peroneal nerve.
      Peroneus longus is innervated by the superficial peroneal nerve.
      Peroneus tertius is innervated by the deep peroneal nerve.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      27.5
      Seconds
  • Question 114 - Regarding the management of gout, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding the management of gout, which of the following statements is CORRECT:

      Your Answer: Colchicine is first line for management of acute gout.

      Correct Answer: Allopurinol may cause an acute attack of gout when first started.

      Explanation:

      Allopurinol is a treatment for the prevention of gout. The initiation of treatment may precipitate an acute attack, and should be covered with an NSAID or colchicine, continued for at least one month after the hyperuricaemia has been corrected. Colchicine is not indicated for long term prevention of gout. NSAIDs are first line for acute gout; colchicine is an alternative in whom NSAIDs are contraindicated, not tolerated or ineffective (including in people taking anticoagulants). Ibuprofen is not recommended for acute gout, given it has only weak anti-inflammatory properties; naproxen, diclofenac or indometacin are indicated instead.

    • This question is part of the following fields:

      • Musculoskeletal
      • Pharmacology
      4
      Seconds
  • Question 115 - The following are all examples of type I hypersensitivity EXCEPT for: ...

    Correct

    • The following are all examples of type I hypersensitivity EXCEPT for:

      Your Answer: Contact dermatitis

      Explanation:

      Examples of type I reactions include:
      Allergic rhinitis
      Allergic conjunctivitis
      Allergic asthma
      Systemic anaphylaxis
      Angioedema
      Urticaria
      Penicillin allergy

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      8.3
      Seconds
  • Question 116 - A 61-year-old patient experiences a spontaneous rupture of his Achilles tendon following a...

    Incorrect

    • A 61-year-old patient experiences a spontaneous rupture of his Achilles tendon following a course of antibiotics

      Which of the antibiotics listed below is MOST likely to be the cause? 

      Your Answer: Metronidazole

      Correct Answer: Ciprofloxacin

      Explanation:

      Tendinopathy and spontaneous tendon rupture are caused by fluoroquinolones, which are an uncommon but well-known cause. Tendon problems caused by fluoroquinolones are expected to affect 15 to 20 people per 100,000. Patients over the age of 60 are most likely to develop them.

      It usually affects the Achilles tendon, but it has also been described in cases involving the quadriceps, peroneus brevis, extensor pollicis longus, long head of biceps brachii, and rotator cuff tendons. The exact aetiology is uncertain, although the fluoroquinolone medication is thought to obstruct collagen activity and/or cut off blood supply to the tendon.

      Other factors linked to tendon rupture spontaneously include:
      Gout
      Treatment with corticosteroids
      Hypercholesterolaemia
      Long-term dialysis
      Kidney transplant
      Rheumatoid arthritis 

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      15.4
      Seconds
  • Question 117 - Which of the following movements is controlled by the pectoralis major muscle? ...

    Incorrect

    • Which of the following movements is controlled by the pectoralis major muscle?

      Your Answer: Extension, abduction and medial rotation of the humerus

      Correct Answer: Flexion, adduction and medial rotation of the humerus

      Explanation:

      The pectoralis major is a muscle that runs across the top of the chest and connects to a ridge on the back of the humerus (the bone of the upper arm).

      Adduction, or lowering, of the arm (opposed to the deltoideus muscle) and rotation of the arm forward around the axis of the body are two of its main functions.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      5.9
      Seconds
  • Question 118 - A 55-year-old female is urgently rushed into the Emergency Department as she complains...

    Correct

    • A 55-year-old female is urgently rushed into the Emergency Department as she complains of chest pain that is worse on breathing, shortness of breath, palpitations, and haemoptysis.

      She undergoes a CT pulmonary angiogram, which reveals a large pulmonary embolus. She is immediately started on heparin and shifted to the acute medical ward.

      Which of the following statements is true regarding heparin?

      Your Answer: It activates antithrombin III

      Explanation:

      Heparin is a polymer of glycosaminoglycan. It occurs naturally and is found in mast cells. Clinically, it is used in two forms:
      1. Unfractionated: widely varying polymer chain lengths
      2. Low molecular weight: Smaller polymers only

      Heparin works by binding to and activating the enzyme inhibitor antithrombin III. Antithrombin III inactivates thrombin (factor IIa) by forming a 1:1 complex with thrombin. The heparin-antithrombin III complex also inhibits factor Xa and some other proteases involved with clotting. The heparin-ATIII complex can also inactivate IX, XI, XII, and plasmin.

      Heparin is not thrombolytic or fibrinolytic. It prevents the progression of existing clots by inhibiting further clotting. The lysis of existing clots relies on endogenous thrombolytics.

      Heparin is used for:
      1. Prevention and treatment of venous thromboembolism
      2. Treatment of disseminated intravascular coagulation
      3. Treatment of fat embolism
      4. Priming of haemodialysis and cardiopulmonary bypass machines

      There is no evidence that heparin is superior to low-molecular-weight heparins in preventing mortality from thrombosis.

      Vitamin K is used to reverse the effects of warfarin but not heparin. For heparin, protamine sulphate is used to counteract its effects.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      21
      Seconds
  • Question 119 - Regarding the management of diabetic ketoacidosis (DKA), insulin should initially be given: ...

    Incorrect

    • Regarding the management of diabetic ketoacidosis (DKA), insulin should initially be given:

      Your Answer: At a concentration of 0.1 units/mL at a fixed rate 0.1 units/kg/hour

      Correct Answer: At a concentration of 1 unit/mL at a fixed rate of 0.1 units/kg/hour

      Explanation:

      An intravenous insulin infusion should be started at a concentration of 1 unit/mL, at a fixed rate of 0.1 units/kg/hour. Established subcutaneous long-acting insulin therapy should be continued concomitantly. Blood ketone and blood glucose concentrations should be checked hourly and the insulin infusion rate adjusted accordingly. Blood ketone concentration should fall by at least 0.5 mmol/litre/hour and blood glucose concentration should fall by at least 3 mmol/litre/hour.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      17.9
      Seconds
  • Question 120 - Regarding CSF (cerebrospinal fluid) production, approximately how much is produced per day? ...

    Incorrect

    • Regarding CSF (cerebrospinal fluid) production, approximately how much is produced per day?

      Your Answer: 50 ml

      Correct Answer: 500 ml

      Explanation:

      CSF fills the ventricular system, a series of interconnected spaces within the brain, and the subarachnoid space directly surrounding the brain. The intraventricular CSF reflects the composition of the brain’s extracellular space via free exchange across the ependyma, and the brain “floats” in the subarachnoid CSF to minimize the effect of external mechanical forces. The volume of CSF within the cerebral ventricles is approximately 30 mL, and that in the subarachnoid space is about 125 mL. Because about 0.35 mL of CSF is produced each minute, CSF is turned over more than three times daily. Approximately 500 mL of CSF is produced per day, at a rate of about 25 mL per hour.

      CSF is a filtrate of capillary blood formed largely by the choroid plexuses, which comprise pia mater, invaginating capillaries, and ependymal cells specialized for transport. The choroid plexuses are located in the lateral, third, and fourth ventricles. The lateral ventricles are situated within the two cerebral hemispheres. They each connect with the third ventricle through one of the interventricular foramina (of Monro). The third ventricle lies in the midline between the diencephalon on the two sides. The cerebral aqueduct (of Sylvius) traverses the midbrain and connects the third ventricle with the fourth ventricle. The fourth ventricle is a space defined by the pons and medulla below and the cerebellum above. The central canal of the spinal cord continues caudally from the fourth ventricle, although in adult humans the canal is not fully patent and continues to close with age.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      8.3
      Seconds
  • Question 121 - From which of the following cell types are platelets derived? ...

    Incorrect

    • From which of the following cell types are platelets derived?

      Your Answer: Promyelocytes

      Correct Answer: Megakaryocytes

      Explanation:

      Synthesis of platelets occurs in the bone marrow by fragmentation of megakaryocytes cytoplasm, derived from the common myeloid progenitor cell. The average time for differentiation of the human stem cell to the production of platelets is about 10 days. The major regulator of platelet formation is thrombopoietin and 95% of this is produced by the liver. Normal platelet count is 150 – 450 x 109/L and the normal lifespan of a platelet is about 10 days. Usually about one-third of the marrow output of platelets may be trapped at any one time in the normal spleen.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      25.3
      Seconds
  • Question 122 - You suspect that your patient with polycystic kidney disease has developed a berry...

    Correct

    • You suspect that your patient with polycystic kidney disease has developed a berry aneurysm as a complication of his disease. The patient complains of a sudden, severe headache. You are guessing subarachnoid haemorrhage secondary to a ruptured berry aneurysm as the cause of his severe headaches. What is the most likely location of his aneurysm?

      Your Answer: Anterior communicating artery

      Explanation:

      One of the complications that polycystic kidney disease may cause is the development of a brain aneurysm.

      A berry aneurysm is the most common type of brain aneurysm.

      The Circle of Willis, where the major blood vessels meet at the base of the brain, is where it usually appears. The most common junctions of the Circle of Willis where an aneurysm may occur include the anterior communicating artery (35%), internal carotid artery (30%), the posterior communicating artery and the middle cerebral artery (22%), and finally, the posterior circulation sites, most commonly the basilar artery tip.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      4.4
      Seconds
  • Question 123 - Regarding bias, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding bias, which of the following statements is CORRECT:

      Your Answer: Bias is only introduced during the study design and analysis phases.

      Correct Answer: Bias leads to the systematic difference between the results from a study and the true states of affair.

      Explanation:

      Bias is the term used to describe an error at any stage of the study that was not due to chance. Bias leads to the systematic difference between the results from a study and the true states of affair. Bias may be introduced at all stages of the research process, from study design, through to analysis and publication. Bias can create a spurious association or mask a real association.Good research design can reduce the effect of bias (e.g. blinding, randomisation) but they cannot eliminate it completely. Increasing the sample size does not reduce bias.

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Study Methodology
      15.9
      Seconds
  • Question 124 - You examine a patient's blood tests and discover that her electrolyte levels are...

    Correct

    • You examine a patient's blood tests and discover that her electrolyte levels are abnormal.

      Which of the following is the major extracellular cation?

      Your Answer: Sodium

      Explanation:

      Electrolytes are compounds that may conduct an electrical current and dissociate in solution. Extracellular and intracellular fluids contain these chemicals. The predominant cation in extracellular fluid is sodium, whereas the major anion is chloride. Potassium is the most abundant cation in the intracellular fluid, while phosphate is the most abundant anion. These electrolytes are necessary for homeostasis to be maintained.

    • This question is part of the following fields:

      • Basic Cellular Physiology
      • Physiology
      9.3
      Seconds
  • Question 125 - An 11-year-old presented to a GP with a history of headache, neck stiffness...

    Incorrect

    • An 11-year-old presented to a GP with a history of headache, neck stiffness and photophobia. On examination, HR is 122, BP is 87/42, RR is 28, SaO 2 is 95%, temperature is 39.4 o C. There is a recent petechial rash on legs and arms. The GP administered a dose of antibiotics in the prehospital setting before transferring to the Emergency Department. Which of these would the GP have administered?

      Your Answer: Oral penicillin V 250 mg

      Correct Answer: IM benzylpenicillin 1.2 g

      Explanation:

      General Practitioners are advised to give a single injection of benzylpenicillin by intravenous or intramuscular injection before transferring the patient urgently to the ED when bacterial meningitis is suspected.

      The recommended doses are:
      Infants under 1 year: 300 mg
      Children ages 1 to 9 years: 600 mg
      Children aged 10 years and over: 1.2g
      Adults: 1.2g

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      8.2
      Seconds
  • Question 126 - A 31-year-old man with sickle-cell disease receives a blood transfusion for symptomatic anaemia....

    Incorrect

    • A 31-year-old man with sickle-cell disease receives a blood transfusion for symptomatic anaemia. He presents to the Emergency Department three weeks later with a rash, fever, and diarrhoea. He has pancytopenia and abnormal liver function results on blood tests.

      Which of the transfusion reactions is most likely to have happened?

      Your Answer: TACO

      Correct Answer: Graft-vs-host disease

      Explanation:

      Blood transfusion can be a life-saving treatment with significant clinical benefits, but it also comes with a number of risks and potential complications, including:
      Immunological side effects
      Errors in administration (episodes of ‘wrong blood’)
      Viruses and Infections (bacterial, viral, possibly prion)
      Immunodilution

      A culture of better safety procedures as well as steps to reduce the use of transfusion has emerged as a result of growing awareness of avoidable risk and improved reporting systems. Transfusion errors, on the other hand, continue to occur, and some serious adverse reactions go unreported.

      Transfusion-associated graft-vs-host disease (TA-GVHD) is a rare blood transfusion complication that causes fever, rash, and diarrhoea 1-4 weeks after the transfusion. Pancytopenia and liver function abnormalities are common laboratory findings.

      TA-GVHD, unlike GVHD following allogeneic marrow transplantation, causes profound marrow aplasia with a mortality rate of >90%. Survival is uncommon, with death occurring within 1-3 weeks of the onset of symptoms.

      Because of immunodeficiency, severe immunosuppression, or shared HLA antigens, viable T lymphocytes in blood components are transfused, engraft, and react against the recipient’s tissues, and the recipient is unable to reject the donor lymphocytes.
      The following is a list of the most common transfusion reactions and complications:

      1) Reaction to a febrile transfusion
      The temperature rises by one degree from the baseline. Chills and malaise are also possible symptoms.
      The most common response (1 in 8 transfusions).
      Cytokines from leukocytes in transfused red cell or platelet components are usually to blame.
      Only supportive. The use of paracetamol is beneficial.

      2) Acute haemolytic reaction is a type of haemolytic reaction that occurs when the
      Fever, chills, pain at the transfusion site, nausea, vomiting, and dark urine are all symptoms of a transfusion reaction.
      Early on, many people report a sense of ‘impending doom.’
      The most serious reaction. ABO incompatibility is frequently caused by a clerical error.
      STOP THE TRANSFUSION OF INFORMATION. IV fluids should be given. It’s possible that diuretics will be required.

      3) Haemolytic reaction that is delayed
      It usually happens 4 to 8 days after a blood transfusion.
      Fever, anaemia, jaundice, and haemoglobinuria are all symptoms that the patient has.
      Positive Coombs test for direct antiglobulin.
      Because of the low titre antibody, it is difficult to detect in a cross-match, and it is unable to cause lysis at the time of transfusion.
      The majority of delayed haemolytic reactions are harmless and do not require treatment.
      Anaemia and renal function should be monitored and treated as needed.

      4) Reaction to allergens
      Foreign plasma proteins are usually to blame, but anti-IgA could also be to blame.
      Urticaria, pruritus, and hives are typical allergic reactions. It’s possible that it’s linked to laryngeal oedema or bronchospasm.
      Anaphylaxis is a rare occurrence.
      Antihistamines can be used to treat allergic reactions symptomatically. It is not necessary to stop transfusions.
      If the patient develops anaphylaxis, the transfusion should be stopped and the patient should be given adrenaline and treated according to the ALS protocol.

      5) TRALI (Transfusion Related Acute Lung Injury)
      Within 6 hours of transfusion, there was a sudden onset of non-cardiogenic pulmonary oedema.
      It’s linked to the presence of antibodies to recipient leukocyte antigens in the donor blood.
      The most common cause of death from transfusion reactions is this.
      STOP THE TRANSFUSION OF INFORMATION. Oxygen should be given to the patient. Around 75% of patients will require aggressive respiratory support.
      The use of diuretics should be avoided.

      6) TACO (Transfusion Associated Circulatory Overload)
      Acute or worsening respiratory distress within 6 hours of a large blood transfusion. Fluid overload and pulmonary and peripheral oedema can be seen. Rapid blood pressure rises are common. BNP is usually 1.5 times higher than it was before the transfusion. It is most common in the elderly and those who have chronic anaemia.

      Blood transfusions should be given slowly, over the course of 3-4 hours.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      7.7
      Seconds
  • Question 127 - The normal range of arterial HCO3- is: ...

    Incorrect

    • The normal range of arterial HCO3- is:

      Your Answer: 16 - 24 mmol/L

      Correct Answer: 24 - 30 mmol/L

      Explanation:

      Normal ranges:
      pH = 7.35 – 7.45
      pO2(on air) = 11 -14 kPa
      pCO2= 4.5 – 6.0 kPa
      HCO3-= 24 – 30 mmol/L
      BE = +/- 2 mmol/L

    • This question is part of the following fields:

      • Physiology
      • Renal
      5.3
      Seconds
  • Question 128 - What is the correct adrenaline dose for a patient with pulseless ventricular tachycardia?...

    Incorrect

    • What is the correct adrenaline dose for a patient with pulseless ventricular tachycardia?

      Your Answer: 0.5 ml of 1 in 1000 adrenaline solution

      Correct Answer: 10 ml of 1 in 10,000 adrenaline solution

      Explanation:

      Ventricular fibrillation or pulseless ventricular tachycardia (VF/VT) are referred to as shockable rhythm.

      IV adrenaline 1 mg (10 mL of 1:10,000 solution) should be administered after 3 shocks and every 3 – 5 minutes/after alternate shocks thereafter for a shockable rhythm.

      For a non-shockable rhythm, 1 mg IV adrenaline should be administered as soon as IV access is obtained, and then every 3 – 5 minutes/after alternate shocks thereafter.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      14.4
      Seconds
  • Question 129 - EMLA cream is a topical local anaesthetic containing which of the following: ...

    Incorrect

    • EMLA cream is a topical local anaesthetic containing which of the following:

      Your Answer: 2.5% lidocaine

      Correct Answer: 50/50 mixture 2.5% lidocaine and 2.5% prilocaine

      Explanation:

      EMLA cream, an effective topical local anaesthetic, is a 50/50 mixture of 2.5% prilocaine and 2.5% lidocaine.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
      5.4
      Seconds
  • Question 130 - Alpha cells of the endocrine pancreas produce which of the following hormones: ...

    Incorrect

    • Alpha cells of the endocrine pancreas produce which of the following hormones:

      Your Answer: Pancreatic polypeptide

      Correct Answer: Glucagon

      Explanation:

      Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
      Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
      Glucagon then causes:
      Glycogenolysis
      Gluconeogenesis
      Lipolysis in adipose tissue
      The secretion of glucagon is also stimulated by:
      Adrenaline
      Cholecystokinin
      Arginine
      Alanine
      Acetylcholine
      The secretion of glucagon is inhibited by:
      Insulin
      Somatostatin
      Increased free fatty acids
      Increased urea production

      Glycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.

      Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      14.5
      Seconds
  • Question 131 - Osteoclasts are a type of bone cell that are critical in the maintenance,...

    Incorrect

    • Osteoclasts are a type of bone cell that are critical in the maintenance, repair and remodelling of bones.
      Which of the following inhibits osteoclast activity? Select ONE answer only.

      Your Answer: 1,25-dihydroxycholecalciferol

      Correct Answer: Calcitonin

      Explanation:

      Osteoclasts are a type of bone cell that breaks down bone tissue. This is a critical function in the maintenance, repair and remodelling of bones. The osteoclast disassembles and digests the composite of hydrated protein and minerals at a molecular level by secreting acid and collagenase. This process is known as bone resorption and also helps to regulate the plasma calcium concentration.
      Osteoclastic activity is controlled by a number of hormones:
      1,25-dihydroxycholecalciferol increases osteoclastic activity
      Parathyroid hormone increases osteoclastic activity
      Calcitonin inhibits osteoclastic activity
      Bisphosphonates are a class of drug that slow down and prevent bone damage. They are osteoclast inhibitors.

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      19.2
      Seconds
  • Question 132 - In the ventricular myocyte action potential, depolarisation occurs through the opening of: ...

    Incorrect

    • In the ventricular myocyte action potential, depolarisation occurs through the opening of:

      Your Answer: Ligand-gated Na + channels

      Correct Answer: Voltage-gated Na + channels

      Explanation:

      An action potential (AP) is initiated when the myocyte is depolarised to a threshold potential of about -65 mV, as a result of transmission from an adjacent myocyte via gap junctions. Fast voltage-gated Na+channels are activated and a Na+influx depolarises the membrane rapidly to about +30 mV. This initial depolarisation is similar to that in nerve and skeletal muscle, and assists the transmission to the next myocyte.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      29.1
      Seconds
  • Question 133 - Which of the following is NOT mainly characterised by intravascular haemolysis: ...

    Incorrect

    • Which of the following is NOT mainly characterised by intravascular haemolysis:

      Your Answer: Paroxysmal nocturnal haemoglobinuria

      Correct Answer: Beta-Thalassaemia

      Explanation:

      Causes of intravascular haemolysis:
      Haemolytic transfusion reactions
      G6PD deficiency
      Red cell fragmentation syndromes
      Some severe autoimmune haemolytic anaemias
      Some drug-and infection-induced haemolytic anaemias
      Paroxysmal nocturnal haemoglobinuria

    • This question is part of the following fields:

      • Haematology
      • Pathology
      19.9
      Seconds
  • Question 134 - Which of the following statements is correct with regards to Horner's syndrome? ...

    Incorrect

    • Which of the following statements is correct with regards to Horner's syndrome?

      Your Answer: Horner's syndrome results from damage to secretomotor parasympathetic fibres.

      Correct Answer: Miosis occurs due to paralysis of the dilator pupillae muscle.

      Explanation:

      The characteristics of Horner’s syndrome are pupil constriction, partial ptosis and anhidrosis.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      15.3
      Seconds
  • Question 135 - A 49-year-old woman has a history of hypertension and persistent hypokalaemia and is...

    Incorrect

    • A 49-year-old woman has a history of hypertension and persistent hypokalaemia and is diagnosed with hyperaldosteronism.

      Which of these is the commonest cause of hyperaldosteronism?

      Your Answer: Diuretic usage

      Correct Answer: Adrenal adenoma

      Explanation:

      When there are excessive circulating levels of aldosterone, hyperaldosteronism occurs. There are two main types of hyperaldosteronism:

      Primary hyperaldosteronism (,95% of cases)
      Secondary hyperaldosteronism (,5% of cases)

      Primary causes of hyperaldosteronism include:
      Adrenal adenoma (Conn’s syndrome)
      Adrenal hyperplasia
      Adrenal cancer
      Familial aldosteronism
      Secondary causes of hyperaldosteronism include:
      Drugs
      Obstructive renal artery disease
      Renal vasoconstriction
      Oedematous disorders syndrome

      Adrenal adenoma is the commonest cause of hyperaldosteronism (seen in ,80% of all cases).

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      19.8
      Seconds
  • Question 136 - Nifedipine commonly causes which of the following adverse effects? ...

    Incorrect

    • Nifedipine commonly causes which of the following adverse effects?

      Your Answer: Precipitation of heart failure

      Correct Answer: Ankle oedema

      Explanation:

      Most common adverse effects of Nifedipine include:
      Peripheral oedema (10-30%)
      Dizziness (23-27%)
      Flushing (23-27%)
      Headache (10-23%)
      Heartburn (11%)
      Nausea (11%)

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      20
      Seconds
  • Question 137 - Which of the following is NOT a typical feature of lithium toxicity: ...

    Incorrect

    • Which of the following is NOT a typical feature of lithium toxicity:

      Your Answer: Confusion

      Correct Answer: Miosis

      Explanation:

      Features of toxicity include:
      Increasing gastrointestinal disturbances (vomiting, diarrhoea, anorexia)
      Visual disturbances
      Polyuria and incontinence
      Muscle weakness and tremor
      Tinnitus
      CNS disturbances (dizziness, confusion and drowsiness increasing to lack of coordination, restlessness, stupor)
      Abnormal reflexes and myoclonus
      Hypernatraemia
      With severe overdosage (serum-lithium concentration > 2 mmol/L) seizures, cardiac arrhythmias (including sinoatrial block, bradycardia and first-degree heart block), blood pressure changes, electrolyte imbalance, circulatory failure, renal failure, coma and sudden death may occur.

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      6.3
      Seconds
  • Question 138 - A 42-year-old woman with a history of hyposplenism arrives at the Emergency Department...

    Incorrect

    • A 42-year-old woman with a history of hyposplenism arrives at the Emergency Department sick and feverish. A complete set of bloods, including a peripheral blood film, is organised.

      On a hyposplenic blood film, which of the following features is LEAST likely to be seen?

      Your Answer: Macrocytosis

      Correct Answer: Teardrop cells

      Explanation:

      The collection of abnormalities found in these patients is referred to as a hyposplenic film.
      The following features can be seen on hyposplenic blood films:
      Howell-Jolly bodies
      Heinz’s bodies
      Target cells
      RBCs with nuclei on occasion
      Lymphocytosis
      Macrocytosis
      Acanthocytes
      Teardrop cells, also known as dacrocytes, are named for their teardrop-shaped shape.

      Dacrocytosis is a condition in which a large number of these cells are present. Myelofibrosis and beta thalassemia major both have dacrocytes, but hyposplenism does not.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      11.6
      Seconds
  • Question 139 - You've been summoned to a young man in the resus area who is...

    Incorrect

    • You've been summoned to a young man in the resus area who is experiencing an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.

      Which of the following is the correct adenosine mechanism of action?

      Your Answer: Blocks K + channels in the heart

      Correct Answer: Opens K + channels in the heart

      Explanation:

      The purine nucleoside adenosine is used to diagnose and treat paroxysmal supraventricular tachycardia. Adenosine works by stimulating A1-adenosine receptors and opening potassium channels that are sensitive to acetylcholine. This causes the atrioventricular (AV) node’s cell membrane to become hyperpolarized, slowing conduction by inhibiting calcium channels.
      Patients who have had a heart transplant are extremely sensitive to the effects of adenosine and should start with a lower dose of 3 mg, then 6 mg, and finally 12 mg.

      Dipyridamole potentiates the effects of adenosine, so it should be used with caution in patients who are taking it.

      The use of adenosine is contraindicated in the following situations:
      Asthma
      COPD (chronic obstructive pulmonary disease)
      Decompensated heart failure 
      Long QT syndrome
      AV block in the second or third degree
      Sinusitis is a condition in which the sinuses become (unless pacemaker fitted)
      Hypotension that is severe

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      7.8
      Seconds
  • Question 140 - A 15-year-old boy was brought to the emergency room with complaints of a...

    Incorrect

    • A 15-year-old boy was brought to the emergency room with complaints of a headache, stiffness of the neck, and photophobia. Upon observation, the following were noted: HR 124, BP 86/43, RR 30, SaO 95%, temperature 39.5 deg C. A recently developed non-blanching rash on his legs was also observed.

      What is most likely the causative agent of the case presented above?

      Your Answer: Neisseria meningitidis group C

      Correct Answer: Neisseria meningitidis group B

      Explanation:

      The meningococcus is solely a human pathogen, and up to 50% of the population may carry meningococci in the nasopharynx. Factors that lead to invasion and production of disease include complex inter-relationships of genetic predisposition, host status, environmental conditions, and virulence of the organism.

      Meningococcal disease is the most common infectious cause of death in childhood in developed countries. It presents as septicaemia, meningitis, or a combination. Septicaemia is the more dangerous presentation, especially with septic shock; meningitis is more likely to lead to neurodevelopmental sequelae. Classic features of septicaemia are a non-blanching rash in a feverish, ill child.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      9.3
      Seconds
  • Question 141 - Which of the following globin chains makes up haemoglobin A2 (HbA2)? ...

    Incorrect

    • Which of the following globin chains makes up haemoglobin A2 (HbA2)?

      Your Answer: Two alpha and two beta chains

      Correct Answer: Two alpha chains and two delta chains

      Explanation:

      Haemoglobin is a 64.4 kd tetramer consisting of two pairs of globin polypeptide chains: one pair of alpha-like chains, and one pair of non-alpha chains. The chains are designated by Greek letters, which are used to describe the particular haemoglobin (e.g., Hb A is alpha2/beta2).

      Two copies of the alpha-globin gene (HBA2, HBA1) are located on chromosome 16 along with the embryonic zeta genes (HBZ). There is no substitute for alpha globin in the formation of any of the normal haemoglobins (Hb) following birth (e.g., Hb A, Hb A2, and Hb F). Thus, absence any alpha globin, as seen when all 4 alpha-globin genes are inactive or deleted is incompatible with extrauterine life, except when extraordinary measures are taken.

      A homotetramer of only alpha-globin chains is not thought to occur, but in the absence of alpha chains, beta and gamma homotetramers (HbH and Bart’s haemoglobin, respectively) can be found, although they lack cooperativity and function poorly in oxygen transport. The single beta-globin gene (HBB) resides on chromosome 11, within a gene cluster consisting of an embryonic beta-like gene, the epsilon gene (HBE1), the duplicated and nearly identical fetal, or gamma globin genes (HBG2, HBG1), and the poorly expressed delta-globin gene (HBD). A heme group, consisting of a single molecule of protoporphyrin IX co-ordinately bound to a single ferrous (Fe2+) ion, is linked covalently at a specific site to each globin chain. If the iron is oxidized to the ferric state (Fe3+), the protein is called methaemoglobin.

      Alpha globin chains contain 141 amino acids (residues) while the beta-like chains contain 146 amino acids. Approximately 75 percent of haemoglobin is in the form of an alpha helix. The non helical stretches permit folding of the polypeptide upon itself. Individual residues can be assigned to one of eight helices (A-H) or to adjacent non helical stretches.

      Heme iron is linked covalently to a histidine at the eighth residue of the F helix (His F8), at residue 87 of the alpha chain and residue 92 of the beta chain. Residues that have charged side groups, such as lysine, arginine, and glutamic acid, lie on the surface of the molecule in contact with the surrounding water solvent. Exposure of the hydrophilic (charged) amino acids to the aqueous milieu is an important determinant of the solubility of haemoglobin within the red blood cell and of the prevention of precipitation.

      The haemoglobin tetramer is a globular molecule (5.0 x 5.4 x 6.4 nm) with a single axis of symmetry. The polypeptide chains are folded such that the four heme groups lie in clefts on the surface of the molecule equidistant from one another.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      9.4
      Seconds
  • Question 142 - In the emergency department, a 50-year-old female appears with a lack of sensation...

    Incorrect

    • In the emergency department, a 50-year-old female appears with a lack of sensation over the front two-thirds of her tongue. Taste and salivation are both present. The patient might have damage which of her nerves?

      Your Answer: Inferior alveolar nerve

      Correct Answer: Lingual nerve

      Explanation:

      The lingual nerve, a branch of the mandibular nerve, transmits sensation to the anterior two-thirds of the tongue.

      The chorda tympani, a branch of the facial nerve, transmits taste to the front two-thirds of the tongue as well as secretomotor innervation to the submandibular and sublingual glands.

      As a result, any damage to the lingual nerve can cause changes in salivary secretion on the affected side, as well as a loss of taste in the anterior two-thirds of the tongue and temporary or permanent sensory changes in the anterior two-thirds of the tongue and the floor of the mouth.

    • This question is part of the following fields:

      • Anatomy
      • Cranial Nerve Lesions
      29.1
      Seconds
  • Question 143 - A 39-year-old man who is suffering from a bacterial infection require antibiotic treatment....

    Correct

    • A 39-year-old man who is suffering from a bacterial infection require antibiotic treatment. You need to figure out which antibiotic is most suitable. Listed below are antimicrobial drugs.

      Which one is a nucleic acid synthesis inhibitor?

      Your Answer: Ciprofloxacin

      Explanation:

      Ciprofloxacin and other quinolone antibiotics work by blocking DNA gyrase, an enzyme that compresses bacterial DNA into supercoils, as well as a type II topoisomerase, which is required for bacterial DNA separation. As a result, they prevent nucleic acid synthesis.
      The following is a summary of the many modes of action of various types of antimicrobial agents:

      Action Mechanisms- Examples:

      Cell wall production is inhibited
      Vancomycin
      Vancomycin
      Cephalosporins

      The function of the cell membrane is disrupted
      Nystatin
      Polymyxins
      Amphotericin B 

      Inhibition of protein synthesis
      Chloramphenicol
      Macrolides
      Aminoglycosides
      Tetracyclines

      Nucleic acid synthesis inhibition
      Quinolones
      Trimethoprim
      Rifampicin
      5-nitroimidazoles
      Sulphonamides
      Anti-metabolic activity
      Isoniazid

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      7.3
      Seconds
  • Question 144 - A 70-year old male is taken to the Emergency Room after suffering a...

    Incorrect

    • A 70-year old male is taken to the Emergency Room after suffering a traumatic fall while showering. Upon physical examination, the attending physician noted a hyperextended neck, 1/5 muscle strength in both upper extremities, 4/5 muscle strength in both lower extremities, and variable loss in sensation. The patient is placed in the wards for monitoring. For the next 24 hours, anuria is noted.

      Which of the following spinal cord injuries is the most likely diagnosis?

      Your Answer: Complete cervical injury

      Correct Answer: Central cord syndrome

      Explanation:

      Central cord syndrome is the most common type of incomplete cord injury and almost always occurs due to a traumatic injury. It results in motor deficits that are worse in the upper extremities as compared to the lower extremities. It may also cause bladder dysfunction (retention) and variable sensory deficits below the level of injury.

      The majority of these patients will be older and present with symptoms after a fall with hyperextension of their neck. On examination, patients will have more significant strength impairments in the upper extremities (especially the hands) compared to the lower extremities. Patients often complain of sensory deficits below the level of injury, but this is variable. Pain and temperature sensations are typically affected, but the sensation of light touch can also be impaired. The most common sensory deficits are in a cape-like distribution across their upper back and down their posterior upper extremities. They will often have neck pain at the site of spinal cord impingement.

      Bladder dysfunction (most commonly urinary retention) and priapism can also be signs of upper motor neuron dysfunction. The sacral sensation is usually preserved, but the clinician should assess the rectal tone to evaluate the severity of the compression.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      8.5
      Seconds
  • Question 145 - A 22-year-old woman comes in with an asthmatic flare. Salbutamol is her only regular...

    Incorrect

    • A 22-year-old woman comes in with an asthmatic flare. Salbutamol is her only regular medication.

      What is the dosage per inhalation of a standard metered dose salbutamol inhaler?

      Your Answer: 200 milligrams

      Correct Answer: 100 micrograms

      Explanation:

      The dose of a conventional metered dose inhaler is 100 micrograms per metered inhalation.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
      11.1
      Seconds
  • Question 146 - Which of the following causes type 1 diabetes mellitus? ...

    Incorrect

    • Which of the following causes type 1 diabetes mellitus?

      Your Answer: Monogenic defects in beta-cell function results in insulin deficiency

      Correct Answer: Autoimmune destruction of beta-cells results in insulin deficiency

      Explanation:

      Type 1 diabetes mellitus results from autoimmune destruction of the insulin-producing beta cells in the islets of Langerhans. This process occurs in genetically susceptible subjects, is probably triggered by one or more environmental agents, and usually progresses over many months or years during which the subject is asymptomatic and euglycemic.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      34.1
      Seconds
  • Question 147 - Dexamethasone would be most useful for which of the following conditions: ...

    Incorrect

    • Dexamethasone would be most useful for which of the following conditions:

      Your Answer: Long-term suppression in rheumatoid arthritis

      Correct Answer: Raised intracranial pressure secondary to malignancy

      Explanation:

      Dexamethasone has a very high glucocorticoid activity in conjunction with insignificant mineralocorticoid activity. This makes it particularly suitable for high-dose therapy in conditions where fluid retention would be a disadvantage such as in the management of raised intracranial pressure or cerebral oedema secondary to malignancy. Dexamethasone also has a long duration of action and this, coupled with its lack of mineralocorticoid action makes it particularly suitable for suppression of corticotropin secretion in congenital adrenal hyperplasia. In most individuals a single dose of dexamethasone at night, is sufficient to inhibit corticotropin secretion for 24 hours. This is the basis of the ‘overnight dexamethasone suppression test’ for diagnosing Cushing’s syndrome.

    • This question is part of the following fields:

      • Endocrine
      • Pharmacology
      8.8
      Seconds
  • Question 148 - A 35-year-old man presents with haemoptysis, night sweats, and weight loss. Further examinations...

    Incorrect

    • A 35-year-old man presents with haemoptysis, night sweats, and weight loss. Further examinations were done and a diagnosis of tuberculosis is suspected.

      Which of the following statements is considered correct regarding Mycobacterium tuberculosis?

      Your Answer: Approximately 90% of patients will develop post-primary tuberculosis

      Correct Answer: It is impervious to decolourisation with acid

      Explanation:

      Mycobacterium tuberculosis are part of the Mycobacteriaceae family. They are described to have the characteristics of a Gram-positive cell wall but they are not easily stained with Gram stain. This is because their cell wall contains a high lipid content, and this lipid allows the Mycobacteria to bind to alkaline stains with the application and help of heat. Once stained, they are able to resist decolorization even with the use of acid alcohol as the decolourizer, making them very difficult to decolorize, that is why they are known to be acid-fast.

      The Ghon complex is a non-pathognomonic radiographic finding on a chest x-ray that is significant for pulmonary infection of tuberculosis. The location of the Ghon’s focus is usually subpleural and predominantly in the upper part of the lower lobe and lower part of the middle or upper lobe.

      Skeletal tuberculosis of the spine is referred to as Pott disease.

      The risk of reactivation TB is about 3.3% during the first year after a positive PPD skin test and a total of 5% to 15% thereafter in the person’s lifetime. Progression from infection to active disease varies with age and the intensity and duration of exposure. Reactivation TB occurs when there is an alteration or suppression of the cellular immune system in the infected host that favours
      replication of the bacilli and progression to disease.

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
      4.5
      Seconds
  • Question 149 - Regarding the varicella zoster virus, which of the following statements is CORRECT: ...

    Correct

    • Regarding the varicella zoster virus, which of the following statements is CORRECT:

      Your Answer: Contracting chickenpox infection while pregnant is associated with a higher risk of developing varicella pneumonitis.

      Explanation:

      Chickenpox infection in neonates, adults/adolescents and pregnant women is associated with more severe disease. Varicella zoster pneumonitis typically occurs in pregnant women or immunocompromised individuals and is associated with a high mortality. A live attenuated-virus vaccine is available and recommended for non-immune healthcare workers but is not part of the routine childhood immunisation schedule. Antiviral treatment is not typically recommended in childhood chickenpox but is indicated for shingles.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      9.7
      Seconds
  • Question 150 - Which of the following is characterised by passive carrier-mediated transport down a chemical...

    Correct

    • Which of the following is characterised by passive carrier-mediated transport down a chemical concentration gradient:

      Your Answer: Facilitated diffusion

      Explanation:

      Facilitated diffusion is the process of spontaneous passive transport of molecules or ions down their concentration gradient across a cell membrane via specific transmembrane transporter (carrier) proteins. The energy required for conformational changes in the transporter protein is provided by the concentration gradient rather than by metabolic activity.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      10.6
      Seconds
  • Question 151 - A patient presents with a cough, productive of green sputum and fever. He...

    Incorrect

    • A patient presents with a cough, productive of green sputum and fever. He was commenced on antibiotics 4 days earlier, but his condition has worsened. There is a documented history of penicillin allergy, and the GP prescribed erythromycin.

      Erythromycin exert its pharmacological effect by binding to?

      Your Answer: The 30S subunit of the bacterial ribosome

      Correct Answer: The 50S subunit of the bacterial ribosome

      Explanation:

      Macrolides are bacteriostatic antibiotics. They act by binding to the 50S subunit of the bacterial ribosome and inhibit translocation, therefore, inhibiting protein synthesis.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      8.3
      Seconds
  • Question 152 - A 30-year-old carpenter presented to the emergency room with a laceration of his...

    Incorrect

    • A 30-year-old carpenter presented to the emergency room with a laceration of his upper volar forearm. Upon further exploration and observation, it was revealed that the nerve that innervates the pronator teres muscle has been damaged.

      Which of the following nerves is most likely damaged in the case?

      Your Answer: The musculocutaneous nerve

      Correct Answer: The median nerve

      Explanation:

      Pronator teres syndrome (PTS) is caused by a compression of the median nerve (MN) by the pronator teres (PT) muscle in the forearm.

      The median nerve, C6 and C7, innervates the pronator teres.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      6.9
      Seconds
  • Question 153 - A 40-year-old female presents to the orthopaedic clinic complaining of pain and limited...

    Incorrect

    • A 40-year-old female presents to the orthopaedic clinic complaining of pain and limited range of motion in the right elbow for the past two days. On examination, the right elbow is extremely tender with erythema and warmth of the overlying skin due to acute inflammation.

      Which ONE of the following statements is true with regards to acute inflammation?

      Your Answer: Bradykinin and histamine cause vasoconstriction

      Correct Answer: Neutrophils are activated and adhere to the endothelium as a result of interaction with endothelial cell adhesion molecules

      Explanation:

      Acute inflammation is defined as inflammation occurring within minutes to hours in response to an injury lasting for less than two weeks.

      Acute inflammation
      Rapid onset (minutes to hours)
      Quick resolution (usually days)

      Chronic inflammation
      May last weeks, months, or years

      There are five cardinal signs of inflammation:
      1) Pain
      2) Redness
      3) Warmth
      4) Oedema
      5) Loss of function

      During acute inflammation, neutrophils are activated and attracted to the site of inflammation in response to various interleukins and cytokines. This process takes place via the following mechanism:
      1) Margination
      Neutrophils flow nearer the vessel wall rather than in the axial stream, which is referred to as margination
      2) Rolling along the surface of vascular endothelium
      3) Adhesion to the endothelium by interaction with adhesion molecules (ICAMS and VCAMS)
      4) Diapedesis is the movement of neutrophils from the endothelial cells into the interstitial space by squeezing through the gaps between adjacent endothelial cells

      Bradykinin and histamine are both responsible for vasodilation which causes oedema and decreases intravascular osmotic pressure.

      Neutrophils dominate early (<2 days)
      – Many in the bloodstream
      – Attach firmly to adhesion molecules
      – Apoptosis after 24-48hrs
      Monocytes/macrophages dominate late (>2 days)
      – Live longer
      – Replicate in tissues

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      20.9
      Seconds
  • Question 154 - A 26-year-old female cuts her hand on a knife while preparing dinner but...

    Incorrect

    • A 26-year-old female cuts her hand on a knife while preparing dinner but the bleeding stops within a few minutes.

      Which one of the following cells will be among the first to be present at the wound site to be involved in haemostasis?

      Your Answer: B-lymphocytes

      Correct Answer: Platelets

      Explanation:

      Platelets are the first cells to be attracted to the wound site due to the release of the Von Willebrand factor from the damaged endothelium. Platelets, in turn, release cytokines such as platelet-derived growth factor, which will attract other inflammatory cells to the wound site.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      3.1
      Seconds
  • Question 155 - A 78-year-old man develops renal impairment and hearing loss after inpatient management...

    Incorrect

    • A 78-year-old man develops renal impairment and hearing loss after inpatient management for sepsis.

      Which of these antibiotics is most likely to have been used?

      Your Answer: Co-amoxiclav

      Correct Answer: Gentamicin

      Explanation:

      Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA, and thus prevents initiation of protein synthesis.

      Two of its most notable side effects are reversible nephrotoxicity(caused by the inhibition of protein synthesis in renal cells, which causes acute tubular necrosis) and hearing loss (caused by damage to the vestibular apparatus of the inner ear).

      Both side effects are dose-related and occur commonly in the elderly.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      5.6
      Seconds
  • Question 156 - All of the statements regarding vascular tone are correct except: ...

    Incorrect

    • All of the statements regarding vascular tone are correct except:

      Your Answer: Vasoconstrictors act by increasing intracellular [Ca 2+ ].

      Correct Answer: Most endogenous vasodilators act by decreasing levels of cAMP or cGMP.

      Explanation:

      Most vasoconstrictors bind to G-protein coupled receptors. These mediate elevation in intracellular [Ca2+] which leads to vascular smooth muscle contraction. Important vasoconstrictors include noradrenaline, endothelin-1 and angiotensin II.

      Increased intracellular Ca2+ is as a result of the release of Ca2+from the sarcoplasmic reticulum and depolarisation and entry of Ca2+via L-type voltage-gated Ca2+channels. Most types of vascular smooth muscle do not generate action potentials – instead, the depolarisation is graded, which allows graded entry of Ca2+.
      sequestration by the sarcoplasmic reticulum Ca2+ATPase, removal from the cell by a plasma membrane Ca2+ATPase and Na+/Ca2+exchange decreases intracellular Ca2+, resulting in vasodilation. Relaxation is a result of most endogenous vasodilators when there is an increase in cyclic guanosine monophosphate (cGMP) like nitric oxide) or cyclic adenosine monophosphate (cAMP) like prostacyclin and beta-adrenergic receptor agonists. These activate protein kinases causing substrate level phosphorylation.
      Clinically effective vasodilators are L-type Ca2+channel blocker drugs.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      7.8
      Seconds
  • Question 157 - Which of the following statement is correct with regards to the female urethra?...

    Correct

    • Which of the following statement is correct with regards to the female urethra?

      Your Answer: The urethra opens in the vestibule that lies between the labia minora.

      Explanation:

      The urethra in women is short (about 4 cm long), and begins at the base of the bladder. Its course runs inferiorly through the urogenital diaphragm, then into the perineum. It then opens in the vestibule which lies between the labia minora. The inferior aspect of the urethra is bound to the anterior surface of the vagina. The urethral opening is anterior to the vaginal opening in the vestibule. As the urethra passes through the pelvic floor, it is surrounded by the external urethral sphincter.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      18.3
      Seconds
  • Question 158 - Which of these is NOT a lithium side effect: ...

    Incorrect

    • Which of these is NOT a lithium side effect:

      Your Answer: Hyperthyroidism

      Correct Answer: Peptic ulcer disease

      Explanation:

      Adverse Effects of lithium Include

      Leucocytosis (most patients)
      Polyuria/polydipsia (30-50%)
      Dry mouth (20-50%)
      Hand tremor (45% initially, 10% after 1 year of treatment)
      Confusion (40%)
      Decreased memory (40%)
      Headache (40%)
      Muscle weakness (30% initially, 1% after 1 year of treatment)
      Electrocardiographic (ECG) changes (20-30%)
      Nausea, vomiting, diarrhoea (10-30% initially, 1-10% after 1-2 years of treatment)
      Hyperreflexia (15%)
      Muscle twitch (15%)
      Vertigo (15%)
      Extrapyramidal symptoms, goitre (5%)
      Hypothyroidism (1-4%)
      Acne (1%)
      Hair thinning (1%)

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      15.3
      Seconds
  • Question 159 - Which of the following best describes a commensal: ...

    Incorrect

    • Which of the following best describes a commensal:

      Your Answer: A organism that is not capable of causing disease

      Correct Answer: An organism that is part of the normal flora

      Explanation:

      A commensal is an organism that is part of the normal flora.

    • This question is part of the following fields:

      • Microbiology
      • Principles
      20.4
      Seconds
  • Question 160 - Which of the following statements concerning the facial nerve is INCORRECT? ...

    Incorrect

    • Which of the following statements concerning the facial nerve is INCORRECT?

      Your Answer: The facial nerve supplies taste to the anterior two-thirds of the tongue.

      Correct Answer: Forehead sparing in facial nerve palsy is indicative of a lower motor neuron lesion.

      Explanation:

      In facial nerve palsy, LMN damage will involve the forehead and there will be an inability to close the eyes due to paralysis of the orbicularis oculi or raise the eyebrows due to paralysis of the occipitofrontalis muscle.
      UMN damage causes sparing of the forehead as the occipitofrontalis and orbicularis oculi muscles have bilateral cortical representation.

    • This question is part of the following fields:

      • Anatomy
      • Cranial Nerve Lesions
      3.8
      Seconds
  • Question 161 - What is the pathophysiology of a phaeochromocytoma: ...

    Incorrect

    • What is the pathophysiology of a phaeochromocytoma:

      Your Answer: ACTH-secreting tumour

      Correct Answer: Catecholamine-secreting tumour

      Explanation:

      Phaeochromocytomas are catecholamine-secreting tumours which occur in about 0.1% of patients with hypertension. In about 90% of cases they arise from the adrenal medulla. The remaining 10%, which arise from extra-adrenal chromaffin tissue, are termed paragangliomas. Common presenting symptoms include one or more of headache, sweating, pallor and palpitations. Less commonly, patients describe anxiety, panic attacks and pyrexia. Hypertension, whether sustained or episodic, is present in at least 90% of patients. Left untreated phaeochromocytoma can occasionally lead to hypertensive crisis, encephalopathy, hyperglycaemia, pulmonary oedema, cardiac arrhythmias, or even death.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      5.2
      Seconds
  • Question 162 - What does the correlation coefficient r = 0 indicate with regards to linear...

    Correct

    • What does the correlation coefficient r = 0 indicate with regards to linear relationships between two variables?

      Your Answer: There is no correlation between two variables

      Explanation:

      r = 0 if there is no correlation between two variables.
      The closer that r is to 0, the weaker the correlation.

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Statistics
      7.1
      Seconds
  • Question 163 - Which of the following is NOT an advantage of a cohort study used...

    Incorrect

    • Which of the following is NOT an advantage of a cohort study used to investigate the relationship between exposure to a risk factor and a future outcome:

      Your Answer: Can measure absolute and relative risk directly

      Correct Answer: Particularly suitable for rare diseases

      Explanation:

      Advantages: ideal for studying associations between an exposure and an outcome when the exposure is uncommon, the time sequence of events can be assessed, they can provide information on a wide range of disease outcomes, the absolute and relative risk of disease can be measured directly, they can give a direct estimation of disease incidence rates
      Disadvantages: costly and can take long periods of time if the outcome is delayed, subject to subject-selection and loss to follow-up bias, large sample size required for rare outcome of interest so it is not useful for rare diseases, prone to confounding

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Study Methodology
      1.5
      Seconds
  • Question 164 - A patient was diagnosed with Erb's palsy as a result of a brachial...

    Incorrect

    • A patient was diagnosed with Erb's palsy as a result of a brachial plexus injury sustained in a car accident and, as a result, suffers from left arm paralysis. The following muscles are affected by the injury, except

      Your Answer: Deltoid

      Correct Answer: Trapezius

      Explanation:

      Damage to the C5 and C6 nerve roots causes Erb’s palsy.

      The spinal accessory nerve (CN XI) innervates the trapezius muscle, thus you would not expect this muscle to be impacted.

      The trapezius is a muscle that runs from the base of the neck across the shoulders and into the centre of the back.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      7.3
      Seconds
  • Question 165 - A dermatological examination of a patient presenting with a lump shows a visible...

    Incorrect

    • A dermatological examination of a patient presenting with a lump shows a visible collection of fluid measuring 0.3 cm in diameter.

      Which one of these best describes the lump you have found on examination?

      Your Answer: Bulla

      Correct Answer: Vesicle

      Explanation:

      A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter.

      A furuncle, or boil, is a pyogenic infection of the hair follicle commonly caused by infection with Staphylococcus aureus.

      A carbuncle is a collection of individual boils clustered together.

      A bulla is a visible collection of clear fluid measuring greater than 0.5 cm in diameter.

      A pustule is a small visible skin elevation containing an accumulation of pus.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      4.9
      Seconds
  • Question 166 - Stimulation of J receptors located on alveolar and bronchial walls results in all...

    Incorrect

    • Stimulation of J receptors located on alveolar and bronchial walls results in all of the following EXCEPT for:

      Your Answer: Hypotension

      Correct Answer: Tachycardia

      Explanation:

      Juxtapulmonary or ‘J’ receptors are located on alveolar and bronchial walls close to the capillaries. Their afferents are small unmyelinated C-fibres or myelinated nerves in the vagus nerve. Activation causes depression of somatic and visceral activity by producing apnoea or rapid shallow breathing, a fall in heart rate and blood pressure, laryngeal constriction and relaxation of skeletal muscles via spinal neurones. J receptors are stimulated by increased alveolar wall fluid, pulmonary congestion and oedema, microembolism and inflammatory mediators. J receptors are thought to be involved in the sensation of dyspnoea in lung disease.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      3.7
      Seconds
  • Question 167 - The weight distribution in a group of patients included in a study was...

    Incorrect

    • The weight distribution in a group of patients included in a study was normal. The patients averaged 80 kg in weight. 5 kg was determined to be the standard deviation. Which of the following statements most accurately describes this group of patients:

      Your Answer: 95% of the patients will weigh between 75 and 85 kg.

      Correct Answer: 68% of the patients will weigh between 75 and 85 kg.

      Explanation:

      We can estimate the range of values that would be anticipated to include particular proportions of observations if we know the mean and standard deviation of a collection of normally distributed data: 68.2 percent of the sample results fall within a one SD range above and below the mean (+/- 1 SD), implying that 68 percent of the patients will weigh between 75 and 85 kg. Because +/- 2 SD encompasses 95.4 percent of the data, around 95 percent of the patients will weigh between 70 and 90 kg. +/- 3 SD encompasses 99.7% of the values, implying that nearly all of the patients will weigh between 65 and 95 kg.

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Statistics
      5.2
      Seconds
  • Question 168 - A patient sustains an injury to the proximal median nerve after falling through...

    Incorrect

    • A patient sustains an injury to the proximal median nerve after falling through a glass door. Which of the following muscles would you not expect to be affected:

      Your Answer: Flexor digitorum profundus

      Correct Answer: Flexor carpi ulnaris

      Explanation:

      All of the muscles in the anterior forearm are innervated by the median nerve, except for the flexor carpi ulnaris and the medial half of the flexor digitorum profundus which are innervated by the ulnar nerve.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      32.8
      Seconds
  • Question 169 - Regarding airway resistance, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding airway resistance, which of the following statements is INCORRECT:

      Your Answer: Air flow is driven by, and is directly proportional to, the mouth-alveolar pressure gradient

      Correct Answer: In the lower respiratory tract, airway resistance is mostly determined by the smallest bronchioles.

      Explanation:

      Airway resistance is primarily determined by the airway radius according to Poiseuille’s law, and whether the flow is laminar or turbulent. The major site of airway resistance is the medium-sized bronchi. The smallest airways would seem to offer the highest resistance, but they do not because of their branching parallel arrangement.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      7.9
      Seconds
  • Question 170 - Antidiuretic hormone (ADH) is synthesised by which of the following: ...

    Incorrect

    • Antidiuretic hormone (ADH) is synthesised by which of the following:

      Your Answer: Posterior pituitary

      Correct Answer: Hypothalamus

      Explanation:

      Antidiuretic hormone is synthesised in the hypothalamus and transported to the posterior pituitary within nerve fibres where it is stored in secretory granules. ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, raising cAMP levels and causing intracellular vesicles to fuse with the apical membrane. In their membrane these vesicles have water channels called aquaporins, which increase the water permeability allowing greater water reabsorption and concentration of urine. Excess levels of ADH results in syndrome of inappropriate ADH secretion (SIADH) characterised by hyponatremia with concomitant hypo-osmolality and high urine osmolality.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      4.5
      Seconds
  • Question 171 - In which part of the gastrointestinal tract is Meckel's diverticulum commonly located? ...

    Incorrect

    • In which part of the gastrointestinal tract is Meckel's diverticulum commonly located?

      Your Answer: Duodenum

      Correct Answer: Ileum

      Explanation:

      Meckel’s diverticulum is the most prevalent congenital anomaly of the gastrointestinal tract, affecting approximately 2% of the general population. Meckel’s diverticulum are designated true diverticula because their walls contain all the layers found in normal small intestine. Their location varies among individual patients, but they are usually found in the ileum within 100 cm of the ileocecal valve.

      Approximately 60% of Meckel’s diverticulum contain heterotopic mucosa, of which over 60% consist of gastric mucosa. Pancreatic acini are the next most common; others include Brunner’s glands, pancreatic islets, colonic mucosa, endometriosis, and hepatobiliary tissues.

      A useful, although crude, mnemonic describing Meckel’s diverticulum is the “rule of twos”: 2% prevalence, 2:1 male predominance, location 2 feet proximal to the ileocecal valve in adults, and half of those who are symptomatic are under 2 years of age.

    • This question is part of the following fields:

      • Abdomen And Pelvis
      • Anatomy
      5.7
      Seconds
  • Question 172 - A 40-year-old man complains of pain and redness in his lower thigh due...

    Incorrect

    • A 40-year-old man complains of pain and redness in his lower thigh due to an insect bite. He was diagnosed with cellulitis. Select the first-line antibiotic for cellulitis.

      Your Answer: Doxycycline

      Correct Answer: Flucloxacillin

      Explanation:

      Cellulitis is most commonly caused by bacteria from the group Aß-hemolytic streptococcus.

      Cellulitis can be caused by animal bites. For uncomplicated cellulitis, flucloxacillin is the first-line antibiotic. Because it is beta-lactamase stable, it is efficient against Staphylococcus aureus.

    • This question is part of the following fields:

      • Infections
      • Microbiology
      26.7
      Seconds
  • Question 173 - How does abciximab mediate its antiplatelet effect: ...

    Incorrect

    • How does abciximab mediate its antiplatelet effect:

      Your Answer: It is a phosphodiesterase inhibitor.

      Correct Answer: It is a GPIIb/IIIa inhibitor.

      Explanation:

      Abciximab, eptifibatide and tirofiban are GPIIb/IIIa inhibitors, inhibiting platelet aggregation by preventing the binding of fibrinogen, von Willebrand factor and other adhesive molecules.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      6.3
      Seconds
  • Question 174 - The last two segments of the nephrons are the distal convoluted tubule (DCT)...

    Incorrect

    • The last two segments of the nephrons are the distal convoluted tubule (DCT) and collecting duct (CD).

      Which cell reabsorbs sodium more in the late DCT and CD?

      Your Answer: Intercalated cells

      Correct Answer: Principal cells

      Explanation:

      The main Na+ reabsorbing cells in the late distal convoluted tubule and collecting duct are the principal cells. These make up the majority of the tubular cells.

      The exchange is driven by the Na.K.ATPase pumps on the basolateral membrane.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      6.6
      Seconds
  • Question 175 - A 6-year-old girl is brought to the nephrology clinic by her mother due...

    Incorrect

    • A 6-year-old girl is brought to the nephrology clinic by her mother due to facial oedema. Her lab workup shows proteinuria of 7 g/24 hours and serum albumin levels of 15 g/L. A diagnosis of Nephrotic Syndrome is made, and corticosteroid therapy is initiated.

      Which one of the following is the most likely cause of nephrotic syndrome in this patient?

      Your Answer: Focal segmental glomerulosclerosis

      Correct Answer: Minimal change disease

      Explanation:

      Minimal Change Disease is the most common cause of Nephrotic Syndrome in the paediatric population. It may be caused by NSAID use. Electron microscopy shows the fusion of foot processes while light microscopy will appear normal.

      Focal segmental glomerulosclerosis causes Nephrotic Syndrome in adults. It is associated with Heroin use and HIV infection. There is a limited response to steroids, and the disease progresses to end-stage renal failure in 5-10 years.

      Diabetic nephropathy occurs after a long period of diabetes due to the deposition of amyloid protein leading to a decrease in glomerular filtration.

      There is no history of Hepatitis B in this patient and no symptoms of liver disease such as jaundice.

      Membranous glomerulonephritis would present with features of Nephritic Syndrome. These would be oedema, haematuria; red blood cell casts in the urine and hypertension.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      6.4
      Seconds
  • Question 176 - When calculating the ventilation over perfusion ratio of a male patient, you should...

    Incorrect

    • When calculating the ventilation over perfusion ratio of a male patient, you should remember the ideal V/Q ratio for this patient to compare with his results. What is the approximate ventilation value for a healthy male patient?

      Your Answer: 1 L/min

      Correct Answer: 5 L/min

      Explanation:

      The ventilation/perfusion ratio (V/Q ratio) is a ratio used to assess the efficiency and adequacy of the matching ventilation and perfusion. The ideal V/Q ratio is 1. In an average healthy male, the ventilation value is approximately 5 L/min and the perfusion value is approximately 5 L/min.

      Any mismatch between ventilation and perfusion will be evident in the V/Q ratio. If perfusion is normal but ventilation is reduced, the V/Q ratio will be less than 1, whereas if ventilation is normal but perfusion is reduced, the V/Q ratio will be greater than 1. If the alveoli were ventilated but not perfused at all, then the V/Q ratio would be infinity.

    • This question is part of the following fields:

      • Physiology
      • Respiratory Physiology
      20.1
      Seconds
  • Question 177 - After an accidental fall, a 75-year-old patient complains of neck pain and weakness...

    Incorrect

    • After an accidental fall, a 75-year-old patient complains of neck pain and weakness in his upper limbs. Select the condition that most likely caused the neck pain and weakness of the upper limbs of the patient.

      Your Answer: Anterior cord syndrome

      Correct Answer: Central cord syndrome

      Explanation:

      The cervical spinal cord is the section of the spinal cord that goes through the bones of the neck.

      It is injured incompletely in the central cord syndrome (CCS). This will result in arm weakness more than leg weakness.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      9.4
      Seconds
  • Question 178 - Which of the following problems is associated with Helicobacter pylori infection? ...

    Incorrect

    • Which of the following problems is associated with Helicobacter pylori infection?

      Your Answer: Reactive arthritis

      Correct Answer: Gastric malignancy

      Explanation:

      Helicobacter pylori is a ubiquitous organism that is present in about 50% of the global population. Chronic infection with H pylori causes atrophic and even metaplastic changes in the stomach, and it has a known association with peptic ulcer disease. The most common route of H pylori infection is either oral-to-oral or faecal-to-oral contact.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      8.1
      Seconds
  • Question 179 - You've been summoned to your Emergency Department resuscitation area to see a patient....

    Correct

    • You've been summoned to your Emergency Department resuscitation area to see a patient. You consider giving him an atropine shot because he is severely bradycardic.

      Which of the following statements about the use of atropine is correct?

      Your Answer: It blocks the effects of the vagus nerve on both the SA and AV nodes

      Explanation:

      At muscarinic receptors, atropine blocks the action of the parasympathetic neurotransmitter acetylcholine. As a result, it inhibits the vagus nerve’s effects on both the SA and AV nodes, increasing sinus automaticity and facilitating AV node conduction.

      At muscarinic receptors, atropine blocks the action of the parasympathetic neurotransmitter acetylcholine. As a result, it inhibits the vagus nerve’s effects on both the SA and AV nodes, increasing sinus automaticity and facilitating AV node conduction.

      The most common cause of asystole during cardiac arrest is primary myocardial pathology, not excessive vagal tone, and there is no evidence that atropine is helpful in the treatment of asystole or PEA. As a result, it is no longer included in the ALS algorithm’s non-shockable section. Atropine is most commonly used in the peri-arrest period. It is used to treat bradycardia (sinus, atrial, or nodal) or AV block when the patient’s haemodynamic condition is compromised by the bradycardia.

      If any of the following adverse features are present, the ALS bradycardia algorithm recommends a dose of 500 mcg IV:
      Shock
      Syncope
      Myocardial ischaemia
      Heart failure

      Atropine is also used for the following purposes:
      Topically as a cycloplegic and mydriatic to the eyes
      To cut down on secretions (e.g. in anaesthesia)
      Organophosphate poisoning is treated with
      Atropine’s side effects are dose-dependent and include:
      Mouth is parched
      Vomiting and nausea
      Vision is hazy
      Retention of urine
      Tachyarrhythmias
      It can also cause severe confusion and hallucinations in patients, especially the elderly.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      15.4
      Seconds
  • Question 180 - A patient has an elevated potassium level of 6.7 mmol/L. All of the...

    Incorrect

    • A patient has an elevated potassium level of 6.7 mmol/L. All of the following conditions may cause elevated potassium levels, except for which one?

      Your Answer: Beta-blockers

      Correct Answer: Bartter’s syndrome

      Explanation:

      Bartter’s syndrome is an autosomal recessive renal tubular disorder characterized by hypokalaemia, hypochloraemia, metabolic alkalosis, and hyperreninemia with normal blood pressure. The underlying kidney abnormality results in excessive urinary losses of sodium, chloride, and potassium.

      Bartter’s syndrome does not cause an elevated potassium level, but instead causes a decrease in its concentration (hypokalaemia). The other choices are causes of hyperkalaemia or elevated potassium levels.

      Renal failure, Addison’s disease (adrenal insufficiency), congenital adrenal hyperplasia, renal tubular acidosis (type 4), rhabdomyolysis, burns and trauma, tumour syndrome, and acidosis are non-drug causes of hyperkalaemia. On the other hand, drugs that can cause hyperkalaemia include ACE inhibitors, angiotensin receptor blockers, NSAIDs, beta-blockers, digoxin, and suxamethonium.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
      5.9
      Seconds
  • Question 181 - Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the...

    Incorrect

    • Adrenocorticotropic hormone release from the anterior pituitary is stimulated by which of the following:

      Your Answer: Cortisol

      Correct Answer: Corticotropin-releasing hormone

      Explanation:

      ACTH secretion is stimulated by corticotropin-releasing hormone (CRH) from the hypothalamus.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      3.4
      Seconds
  • Question 182 - A patient suffers a stab wound to the neck. The entry point of...

    Incorrect

    • A patient suffers a stab wound to the neck. The entry point of the blade is situated within the anterior triangle of the neck.
      Which of the following muscles is most likely to be involved? Select ONE answer only.

      Your Answer: Levator scapulae

      Correct Answer: Sternothyroid

      Explanation:

      The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
      Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
      Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
      Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
      Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
      Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerve

      The posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
      Contents:
      Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
      Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      10
      Seconds
  • Question 183 - After collapsing in his nursing home, a 70-year-old man is brought into the...

    Correct

    • After collapsing in his nursing home, a 70-year-old man is brought into the ER. He is a known case of diabetes mellitus and is on medication for it. An RBS of 2.5 mmol/L (3.9-5.5 mmol/L) is recorded in the ER.

      Out of the following, which medication for diabetes mellitus is MOST likely responsible for his hypoglycaemic episode?

      Your Answer: Pioglitazone

      Explanation:

      Pioglitazone is used to treat type 2 diabetes mellitus. It selectively stimulates the nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-γ) and to a lesser extent PPAR-α.

      Of the medications mentioned in this question, only pioglitazone is a recognized cause of hypoglycaemia.

    • This question is part of the following fields:

      • Endocrine Pharmacology
      • Pharmacology
      6
      Seconds
  • Question 184 - C3 deficiency leads to particular susceptibility of infection with which of the following:...

    Incorrect

    • C3 deficiency leads to particular susceptibility of infection with which of the following:

      Your Answer: Intracellular bacteria

      Correct Answer: Encapsulated bacteria

      Explanation:

      Macrophages and neutrophils have C3b receptors and they phagocytose C3b-coated cells. C3 deficiency thus leads to increased susceptibility of infection with encapsulated organisms (e.g. S. pneumoniae, H. influenzae).The early stages of the complement cascade leading to coating of the cells with C3b can occur by two different pathways:The classical pathway usually activated by IgG or IgM coating of cellsThe alternative pathway which is more rapid and activated by IgA, endotoxin and other factors

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      72.2
      Seconds
  • Question 185 - Which of the following drugs decreases plasma-theophylline levels: ...

    Incorrect

    • Which of the following drugs decreases plasma-theophylline levels:

      Your Answer: Erythromycin

      Correct Answer: Carbamazepine

      Explanation:

      Examples of enzyme-inhibiting drugs (raise plasma theophylline level):
      Erythromycin
      Clarithromycin
      Ciprofloxacin
      Fluconazole
      Verapamil
      Allopurinol
      Cimetidine
      Examples of enzyme-inducing drugs (lower plasma theophylline level):
      Primidone
      Phenobarbital
      Carbamazepine
      Phenytoin
      Ritonavir
      Rifampicin
      St John’s Wort

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory
      16.7
      Seconds
  • Question 186 - An 11-year-old boy was brought to the emergency room due to fever and...

    Incorrect

    • An 11-year-old boy was brought to the emergency room due to fever and pain in the ears. Upon physical examination, it was observed that the mastoid area is erythematous and there is a presence of a boggy, tender mass. A diagnosis of acute mastoiditis was made.

      Which of the following parts of the temporal bone is most likely involved?

      Your Answer: Zygomatic process

      Correct Answer: Petrous part

      Explanation:

      Mastoiditis is the inflammation of a portion of the temporal bone referred to as the mastoid air cells. The mastoid air cells are epithelium lined bone septations that are continuous with the middle ear cavity.

      The temporal bone is composed of four parts: the mastoid process, the petrous pyramid, the squamous, and tympanic portions. The mastoid process and the petrous pyramid are the portions of particular interest because of the prevalence of suppurations within these parts of the temporal bone.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
      6.1
      Seconds
  • Question 187 - Which of the following clinical features would you least expect to see in...

    Incorrect

    • Which of the following clinical features would you least expect to see in a lesion of the frontal lobe:

      Your Answer: Primitive reflexes

      Correct Answer: Contralateral homonymous hemianopia with macular sparing

      Explanation:

      Contralateral homonymous hemianopia with macular sparing results from damage to the primary visual cortex of the occipital lobe. Incontinence may occur due to damage of the cortical micturition centre in the prefrontal cortex. Primitive reflexes and inability to problem solve may occur due to damage to the prefrontal cortex. Motor weakness of the contralateral limb with UMN signs may occur due to damage of the primary motor cortex.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      6.9
      Seconds
  • Question 188 - Which of the following is where the rectovesical fascia is located: ...

    Incorrect

    • Which of the following is where the rectovesical fascia is located:

      Your Answer: Between the ampulla of the rectum and the sacrum

      Correct Answer: Between the fundus of the bladder and the ampulla of the rectum

      Explanation:

      In a triangular area between the vasa deferentia, the bladder and rectum are separated only by rectovesical fascia, commonly known as Denonvillier’s fascia.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      17.6
      Seconds
  • Question 189 - Which of the following drugs is first line treatment for a stable regular...

    Correct

    • Which of the following drugs is first line treatment for a stable regular broad-complex tachycardia:

      Your Answer: Amiodarone

      Explanation:

      A regular broad-complex tachycardia is likely to be ventricular tachycardia or a regular supraventricular rhythm with bundle branch block. A ventricular tachycardia (or broad-complex tachycardia of uncertain origin) should be treated with amiodarone 300 mg IV over 10 – 60 min, followed by an infusion of 900 mg over the next 24 hours. If previously confirmed as SVT with bundle branch block, the patient should be treated as for narrow-complex tachycardia.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      22.2
      Seconds
  • Question 190 - A 60-year-old man with insulin-controlled diabetes mellitus asks you about how his ability...

    Incorrect

    • A 60-year-old man with insulin-controlled diabetes mellitus asks you about how his ability to drive is affected. He owns a car as well as a motorcycle.

      Which of the following statements about driving with diabetes under insulin control is correct?

      Your Answer:

      Correct Answer: He must monitor his blood glucose levels every 2 hours whilst driving

      Explanation:

      The DVLA sends a detailed information sheet about their licence and driving to all drivers with diabetes mellitus. The primary danger of driving while diabetic is hypoglycaemia.

      The DVLA must be notified of the following diabetic patients:
      All of the drivers are on insulin. (Licenses are being reviewed more frequently.)
      Those who are at high risk of hypoglycaemia and have had more than one episode of severe hypoglycaemia in the previous year. (Severe hypoglycaemia is defined as requiring the assistance of another person to manage.)
      Those who are unaware of their hypoglycaemia
      Anyone who has ever been in a car accident due to hypoglycaemia
      Anyone with diabetic retinopathy who needs laser treatment (to both eyes or to a second eye if sight only in one eye)
      Patients with diabetes complications that impair their ability to drive.

      To drive, drivers with insulin-treated diabetes must meet the following requirements:
      They need to be aware of hypoglycaemia.
      They must not have had more than one episode of hypoglycaemia in the previous 12 months that necessitated the assistance of another person.
      They must check their blood glucose levels no later than 2 hours before the first journey.
      While driving, they must check their blood glucose levels every two hours.
      The visual acuity and visual field standards must be met.

      Any significant changes in their condition must be reported to the DVLA. Furthermore, on days when they are not driving, group 2 licence holders must test their blood glucose twice daily using a metre that can store three months’ worth of readings.

      In addition to this advice, the DVLA also offers the following advice to diabetic patients:
      When taking tablets that have the potential to cause hypoglycaemia (such as sulfonylureas and glinides), monitoring may be necessary if there has been more than one episode of severe hypoglycaemia.
      Drivers must show good control and be able to recognise hypoglycaemia.
      Verify that your vision meets the required standard.

      If a patient feels hypoglycaemic or has a blood glucose level of less than 4.0 mmol/L, they should not drive. Driving should not be resumed until blood glucose levels have returned to normal, which should take 45 minutes.

      If there are any warning signs, patients should carry rapidly absorbed sugar in their vehicle and stop, turn off the ignition, and eat it.

      If resuscitation is required, a card stating which medications they are taking should be carried.

      If hypoglycaemia causes an accident, a diabetic driver may be charged with driving under the influence of drugs.

    • This question is part of the following fields:

      • Endocrine Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 191 - You suspected a fungal nail infection in a 50-year-old man who presented with...

    Incorrect

    • You suspected a fungal nail infection in a 50-year-old man who presented with an itchy, scaly rash between his toes and a thicker, discoloured nail on his big toe that has been there for almost one month already. Which of the following tests is most likely to confirm your suspected diagnosis?

      Your Answer:

      Correct Answer: Nail clippings for microscopy and culture

      Explanation:

      Nail clippings for microscopy and culture are a diagnostic test for fungal infection. Because some fungi are restricted to the lower parts of the nail, clippings should be taken from the discoloured or brittle parts and cut back as far as possible from the free edge.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
      0
      Seconds
  • Question 192 - Which lobe of the prostate gland is most commonly affected in benign prostatic...

    Incorrect

    • Which lobe of the prostate gland is most commonly affected in benign prostatic hypertrophy?

      Your Answer:

      Correct Answer: Median

      Explanation:

      Benign enlargement of the prostate is common in men older than 50 years. The cause is possibly an imbalance in the hormonal control of the gland. The median lobe of the gland enlarges upward and encroaches within the sphincter vesicae, located at the neck of the bladder. The leakage of urine into the prostatic urethra causes an intense reflex desire to micturate. The enlargement of the median and lateral lobes of the gland produces elongation and lateral compression and distortion of the urethra so that the patient experiences difficulty in passing urine and the stream is weak. Back-pressure effects on the ureters and both kidneys are a common complication. The enlargement of the uvula vesicae (owing to the enlarged median lobe) results in the formation of a pouch of stagnant urine behind the urethral orifice within the bladder. The stagnant urine frequently becomes infected, and the inflamed bladder (cystitis) adds to the patient’s symptoms.

      In all operations on the prostate, the surgeon regards the prostatic venous plexus with respect. The veins have thin walls, are valveless, and are drained by several large trunks directly into the internal iliac veins. Damage to these veins can result in a severe haemorrhage.

    • This question is part of the following fields:

      • Abdomen And Pelvis
      • Anatomy
      0
      Seconds
  • Question 193 - A 39-year-old woman is feeling unwell one week after a parathyroid surgery.

    Which of...

    Incorrect

    • A 39-year-old woman is feeling unwell one week after a parathyroid surgery.

      Which of the following stimulates release of parathyroid hormone (PTH)?

      Your Answer:

      Correct Answer: Increased plasma phosphate concentration

      Explanation:

      PTH is synthesised and released from the chief cells of the four parathyroid glands located behind the thyroid gland.
      It is a polypeptide containing 84 amino acids and it controls free calcium in the body.

      The following stimuli causes release of PTH:
      Increased plasma phosphate concentration
      Decreased plasma calcium concentration

      PTH release is inhibited by:
      Normal or increased plasma calcium concentration
      Hypomagnesaemia

      The main actions of PTH are:
      Increases plasma calcium concentration
      Decreases plasma phosphate concentration
      Increases osteoclastic activity (increasing calcium and phosphate resorption from bone)
      Increases renal tubular reabsorption of calcium
      Decreases renal phosphate reabsorption
      Increases renal conversion of 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol (via stimulation of 1-alpha hydroxylase)
      Increases calcium and phosphate absorption in the small intestine (indirectly via increased 1,25-dihydroxycholecalciferol)

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
      0
      Seconds
  • Question 194 - A 24-year-old male presents to the Emergency Department with a three-day history of...

    Incorrect

    • A 24-year-old male presents to the Emergency Department with a three-day history of high-grade fever, headache and rash along with neck stiffness. On examination, Kernig's sign is positive, and you note a petechial rash over the trunk and limbs. Her vital signs show tachycardia and hypotension. Based on these findings, you diagnose sepsis secondary to meningitis.

      Which one of the following definitions of sepsis is currently accepted?

      Your Answer:

      Correct Answer: Life-threatening organ dysfunction caused by a dysregulated host response to infection

      Explanation:

      In 2016 the SOFA guideline was introduced, also called the Sepsis-related Organ Failure Assessment, to make a sepsis diagnosis easier and prevent mortality.

      According to this guideline, sepsis was defined as a life-threatening organ dysfunction due to a dysregulated host response to infection.

      Septic shock was defined as a subset of sepsis in which the circulatory and metabolic abnormalities would lead to a greater risk of mortality than sepsis alone. Patients with septic shock would be clinically identified by a need for vasopressors to maintain MAP greater than 65 mmHg and serum lactate greater than two mmol/L.

    • This question is part of the following fields:

      • Pathology
      • Pathology Of Infections
      0
      Seconds
  • Question 195 - As a result of a cardiovascular drug she was prescribed, a 67-year-old woman...

    Incorrect

    • As a result of a cardiovascular drug she was prescribed, a 67-year-old woman develops corneal microdeposits.

      Which of the following drugs is the MOST LIKELY cause?

      Your Answer:

      Correct Answer: Amiodarone

      Explanation:

      Corneal microdeposits are almost universally present (over 90%) in people who have been taking amiodarone for more than six months, especially at doses above 400 mg/day. Although these deposits usually cause no symptoms, about 10% of patients report seeing a ‘bluish halo.’ This goes away once the treatment is stopped, and it rarely causes vision problems.

      Other effects of amiodarone on the eye are much rarer, occurring in only 1-2 percent of patients:
      Optic neuropathy is a condition that affects the eyes.
      Non-arteritic anterior ischaemic optic neuropathy (N-AION)
      Swelling of the optic disc

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 196 - Which of the following statements is false regarding the biceps brachii muscle? ...

    Incorrect

    • Which of the following statements is false regarding the biceps brachii muscle?

      Your Answer:

      Correct Answer: It pronates the radioulnar joint in the forearm

      Explanation:

      The biceps brachii muscle is one of the chief muscles of the arm. The origin at the scapula and the insertion into the radius of the biceps brachii means it can act on both the shoulder joint and the elbow joint, which is why this muscle participates in a few movements of the arm. It derives its name from its two heads which merge in one unique distal body, defining the unusual structure of the muscle.

      The biceps brachii muscle is supplied by the musculocutaneous nerve (C5-C6), a branch of the brachial plexus.

      Arterial supply to the biceps brachii muscle varies considerably, coming from up to eight vessels originating from the brachial artery in the middle third of the arm.

      In the shoulder joint both muscle heads partially enforce opposite movements. The long head pulls the arm away from the trunk (abduction) and turns it inwards (inward rotation) whereas the short head pulls the arm back towards the trunk (adduction). When both heads contract simultaneously it leads to an arm bend (flexion). In the elbow joint the muscle bends the forearm (flexion) and rotates it outwards (supination). The supination is most powerful in a flexed elbow. In addition to the movement functions, the biceps has the important task to support the humeral head within the shoulder joint. Its antagonist is the triceps brachii in the posterior compartment of the arm.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      0
      Seconds
  • Question 197 - Regarding cortical areas, which one is found in the posterior part of the...

    Incorrect

    • Regarding cortical areas, which one is found in the posterior part of the inferior frontal gyrus?

      Your Answer:

      Correct Answer: Broca’s area

      Explanation:

      Broca’s area is involved in the expressive aspects of spoken and written language (production of sentences constrained by the rules of grammar and syntax). It corresponds to the opercular and triangular parts of the inferior frontal gyrus (BA 44 and 45). These areas are defined by two rami (branches) of the lateral sulcus (one ascending, one horizontal) which ‘slice into’ the inferior frontal gyrus. In keeping with its role in speech and language, Broca’s area is immediately anterior to the motor and premotor representations of the face, tongue and larynx. A homologous area in the opposite hemisphere is involved in non-verbal communication such as facial expression, gesticulation and modulation of the rate, rhythm and intonation of speech.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
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      Seconds
  • Question 198 - Regarding non-Hodgkin lymphoma (NHL), which of the following statements is CORRECT: ...

    Incorrect

    • Regarding non-Hodgkin lymphoma (NHL), which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: There is a much greater predilection to disseminate to extranodal sites than in Hodgkin lymphoma.

      Explanation:

      Non-Hodgkin’s lymphoma (NHL) refers to a group of lymphoproliferative malignancies (about 85% of B-cell and 15% of T or NK (natural killer) cell origin) with different behavioural patterns and treatment responses. This group of malignancies encompasses all types of lymphoma without Reed-Sternberg cells being present. The Reed-Sternberg cell is classically seen in Hodgkin’s lymphoma.
      NHL is five times as common as Hodgkin’s lymphoma. The peak incidence of NHL is in the 50-70 years age group, it affects men and women equally, but affects the Caucasian population more commonly than black and Asian ethnic groups.
      The following are recognised risk factors for NHL:
      Chromosomal translocations and molecular rearrangements
      Epstein-Barr virus infection
      Human T-cell leukaemia virus type-1 (HTLV-1)
      Hepatitis C
      Congenital and acquired immunodeficiency states
      Autoimmune disorders, e.g. Sjogren’s syndrome and Hashimoto’s thyroiditis
      The most common clinical features at presentation are:
      Lymphadenopathy (typically asymmetrical and painless)
      Weight loss
      Fatigue
      Night sweats
      Hepatosplenomegaly
      For clinical purposes, NHL is divided into three groups: indolent, high-grade, and lymphoblastic.
      Indolent (low-grade) NHL:
      The cells are relatively mature
      Disease follows an indolent course without treatment
      Often acceptable to follow a ‘watch and wait’ strategy
      Local radiotherapy often effective
      Relatively good prognosis with median survival of 10 years
      High-grade NHL:
      Cells are immature
      Disease progresses rapidly without treatment
      Significant number of patients can be cured with intensive combination chemotherapy regimens
      Approximately 40% cure rate
      Lymphoblastic NHL:
      Cells are very immature and have a propensity to involve the CNS
      Treatment and progression are similar to that of acute lymphoblastic leukaemia (ALL)

    • This question is part of the following fields:

      • Haematology
      • Pathology
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  • Question 199 - The Meissner’s plexus acts as the main control for gastrointestinal secretion and local...

    Incorrect

    • The Meissner’s plexus acts as the main control for gastrointestinal secretion and local blood flow within the gut.

      The Meissner’s plexus lies in which layer of the gut wall?

      Your Answer:

      Correct Answer: Submucosa

      Explanation:

      The Meissner’s plexus (submucosal plexus), an enteric nervous plexus, acts as the main control for gastrointestinal secretion and local blood flow within the gut.

      It is located in the submucosal layer on the inner surface of the muscularis externa.

    • This question is part of the following fields:

      • Gastrointestinal Physiology
      • Physiology
      0
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  • Question 200 - A patient presents complaining of visual loss. On examination you note a contralateral...

    Incorrect

    • A patient presents complaining of visual loss. On examination you note a contralateral homonymous hemianopia. Where is the most likely site of the lesion:

      Your Answer:

      Correct Answer: Optic tract

      Explanation:

      At the optic chiasm, fibres from the medial (nasal) half of each retina crossover, forming the right and left optic tracts.
      The left optic tract contains fibres from the left lateral (temporal) retina and the right medial retina.
      The right optic tract contains fibres from the right lateral retina and the left medial retina.
      Each optic tract travels to its corresponding cerebral hemisphere to reach its lateral geniculate nucleus (LGN) located in the thalamus where the fibres synapse.
      A lesion of the optic tract will cause a contralateral homonymous hemianopia.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
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SESSION STATS - PERFORMANCE PER SPECIALTY

Physiology (31/43) 72%
Renal Physiology (2/5) 40%
Anatomy (27/45) 60%
Thorax (2/4) 50%
Microbiology (21/25) 84%
Pathogens (7/9) 78%
Specific Pathogen Groups (9/10) 90%
Immune Responses (4/7) 57%
Pathology (13/23) 57%
Haematology (7/10) 70%
Basic Cellular (3/5) 60%
Cardiovascular (7/10) 70%
Endocrine Physiology (5/7) 71%
Infections (13/17) 76%
Pharmacology (39/53) 74%
Central Nervous System (15/16) 94%
Respiratory Pharmacology (2/4) 50%
Cardiovascular Pharmacology (6/9) 67%
Upper Limb (4/12) 33%
Respiratory Physiology (2/2) 100%
Gastrointestinal Pharmacology (1/1) 100%
Gastrointestinal (2/4) 50%
Inflammatory Responses (0/2) 0%
Basic Cellular Physiology (2/2) 100%
Endocrine (8/9) 89%
Lower Limb (0/5) 0%
CNS Pharmacology (3/3) 100%
Respiratory (3/6) 50%
Head And Neck (5/5) 100%
Cardiovascular Physiology (1/1) 100%
Cranial Nerve Lesions (1/3) 33%
Renal (3/3) 100%
Principles Of Microbiology (1/1) 100%
Musculoskeletal (1/2) 50%
Abdomen (3/3) 100%
Musculoskeletal Pharmacology (1/1) 100%
Anaesthesia (1/1) 100%
General Pathology (1/3) 33%
Principles (1/1) 100%
Abdomen And Pelvis (2/2) 100%
Endocrine Pharmacology (1/2) 50%
Pathology Of Infections (1/1) 100%
Gastrointestinal Physiology (1/1) 100%
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