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Question 1
Correct
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A patient complains of stomach ache. You see a midline scar in the epigastric area when you examine the abdomen. Upon further interrogation, the patient reveals that she had a subtotal gastrectomy for recurring stomach ulcers several years ago. The stomach mucosa secretes a variety of vital compounds, and her ability to secrete some of these molecules has been harmed as a result of his surgery.
The stomach D-cells secrete which of the following substances?
Your Answer: Somatostatin
Explanation:Somatostatin-producing cells present in the pyloric antrum, duodenum, and pancreatic islets are known as D-cells or delta-cells. Somatostatin inhibits gastric acid secretion by acting directly on acid-producing parietal cells in the stomach via a G-protein coupled receptor. By suppressing the release of other hormones such as gastrin, secretin, and histamine, somatostatin can indirectly reduce stomach acid output, slowing the digesting process.
The table below summarizes the many cell types found in the stomach, as well as the substances secreted by each cell type and the function of the secretion:Cell type/ Substance secreted/ Function of secretion
Parietal cells/ Hydrochloric acid/ Kills microbes and activates pepsinogen
Parietal cells/ Intrinsic factor/Binds to vitamin B12 and facilitates its absorption
Chief cells/ Pepsinogen/ Protein digestion
Chief cells/ Gastric lipase/ Fat digestion
G-cells/ Gastrin/ Stimulates gastric acid secretion
Enterochromaffin-like cells (ECL cells) /Histamine/ Stimulates gastric acid secretion
Mucous-neck cells/ Mucous and bicarbonate/ Protects stomach epithelium from acid
D-cells/ Somatostatin/ Inhibits gastric acid secretion -
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 2
Correct
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The cutaneous circulation's principal role is thermoregulation. This process is aided by the existence of arteriovenous anastomoses.
Which of the following anatomical areas has the greatest number of arteriovenous anastomoses?Your Answer: Pinna of the ear
Explanation:Short vessels called arteriovenous anastomoses (AVAs) link tiny arteries and veins. They have a large lumen diameter. The strong and muscular walls allow AVAs to completely clog the vascular lumen, preventing blood flow from artery to vein (acting like a sphincter). When the AVAs open, they create a low-resistance connection between arteries and veins, allowing blood to flow into the limbs’ superficial venous plexuses. There is no diffusion of solutes or fluid into the interstitium due to their strong muscle walls.
AVAs are densely innervated by adrenergic fibres from the hypothalamic temperature-regulation centre. High sympathetic output occurs at normal core temperatures, inducing vasoconstriction of the AVAs and blood flow through the capillary networks and deep plexuses. When the temperature rises, sympathetic output decreases, producing AVA vasodilation and blood shunting from the artery to the superficial venous plexus. Heat is lost to the environment as hot blood rushes near to the skin’s surface.
AVAs are a specialized anatomical adaptation that can only be found in large quantities in the fingers, palms, soles, lips, and pinna of the ear. -
This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 3
Correct
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You examine a 72-year-old man who has recently begun bumetanide treatment for worsening heart failure.
Which of these statements about bumetanide is correct?Your Answer: It has better intestinal absorption than furosemide
Explanation:Bumetanide is a loop diuretic that is used to treat congestive heart failure. It is frequently used in patients who have failed to respond to high doses of furosemide.
It has a potency of about 40 times that of furosemide, with a 1 mg dose being roughly equivalent to a 40 mg dose of furosemide.
Seizures are not known to be triggered by bumetanide. In fact, it lowers the concentration of neuronal chloride, making GABA’s action more depolarizing, and it’s currently being tested as an antiepileptic in the neonatal period.It takes effect after 1 hour of oral administration, and diuresis takes 6 hours to complete.
Bumetanide absorbs much better in the intestine than furosemide. Because it has a higher bioavailability than furosemide, it is commonly used in patients with gut oedema.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 4
Correct
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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 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.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 5
Correct
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During her pregnancy, a 28-year-old lady was given an antibiotic. The neonate was prematurely born with cyanosis and ashen grey coloured skin as a result of this. Other symptoms were hypotonia, low blood pressure, and poor feeding.
From the  following antibiotics, which one is most likely to cause this side effect?Your Answer: Chloramphenicol
Explanation:Grey baby syndrome is a rare but causes significant adverse effect caused by the build-up of chloramphenicol in neonates (particularly preterm babies).
The following are the main characteristics of ‘grey baby syndrome’:
Skin that is ashy grey in colour.
Feeding problems
Vomiting
Cyanosis
Hypotension
Hypothermia
Hypotonia
Collapse of the cardiovascular system
Distension of the abdomen
trouble breathing -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 6
Correct
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Regarding Clostridium species, which of the following statements is INCORRECT:
Your Answer: They are facultative anaerobes.
Explanation:Clostridium spp. are obligatory anaerobic spore-forming Gram-positive bacilli. Toxin production is the main pathogenicity mechanism.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 7
Correct
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All of the following statements are correct regarding the management of acute asthma in adults except:
Your 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).
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This question is part of the following fields:
- Pharmacology
- Respiratory
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Question 8
Correct
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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: 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.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 9
Correct
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Polyuria and polydipsia develop in a patient with a history of affective disorder, who has been on long-term lithium treatment. She has a fluid deprivation test done because she is suspected of having nephrogenic diabetic insipidus. Which of the following urine osmolality findings would be the most reliable in confirming the diagnosis?
Your Answer: After fluid deprivation <300 mosmol/kg, after IM desmopressin >800 mosmol/kg
Explanation:The inability to produce concentrated urine is a symptom of diabetes insipidus. Excessive thirst, polyuria, and polydipsia are all symptoms of this condition. There are two forms of diabetes insipidus: Nephrogenic diabetes insipidus and cranial (central) diabetes insipidus.
A lack of ADH causes cranial diabetic insipidus. Patients with cranial diabetes insipidus can have a urine output of up to 10-15 litres per 24 hours, however most patients can maintain normonatraemia with proper fluid consumption. Thirty percent of cases are idiopathic, while another thirty percent are caused by head injuries. Neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis), and medicines like naloxone and phenytoin are among the other reasons. There is also a very rare hereditary type that is linked to diabetes, optic atrophy, nerve deafness, and bladder atonia.
Renal resistance to the action of ADH causes nephrogenic diabetes insipidus. Urine output is significantly increased, as it is in cranial diabetes insipidus. Secondary polydipsia can keep serum sodium levels stable or raise them. Chronic renal dysfunction, metabolic diseases (e.g., hypercalcaemia and hypokalaemia), and medications, such as long-term lithium use and demeclocycline, are all causes of nephrogenic diabetes insipidus.
The best test to establish if a patient has diabetes insipidus vs another cause of polydipsia is the water deprivation test, commonly known as the fluid deprivation test. It also aids in the distinction between cranial and nephrogenic diabetes insipidus. Weight, urine volume, urine osmolality, and serum osmolality are all measured after patients are denied water for up to 8 hours. At the end of the 8-hour period, 2 micrograms of IM desmopressin is given, and measures are taken again at 16 hours.
The following are the way results are interpreted:
Urine osmolality after fluid deprivation : Urine osmolality after IM desmopressin
Cranial diabetes insipidus: <300 mosmol/kg : >800 mosmol/kg
Nephrogenic diabetes insipidus: <300 mosmol/kg : <300 mosmol/kg
Primary polydipsia: >800 mosmol/kg : >800 mosmol/kg -
This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 10
Correct
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A 23-year-old man is discovered to have an infection from Helicobacter pylori.
Which of the following types of cancer is mostly associated with Helicobacter pylori infection?Your Answer: Gastric cancer
Explanation:H. pylori is recognized as a major cause of type B gastritis, a chronic condition formerly associated primarily with stress and chemical irritants. In addition, the strong association between long-term H. pylori infection and gastric cancer has raised more questions regarding the clinical significance of this organism. There is speculation that long-term H. pylori infection resulting in chronic gastritis is an important risk factor for gastric carcinoma resulting in H. pylori being classified as a carcinogen.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 11
Incorrect
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Which of the following serology results is consistent with chronic hepatitis B infection:
Your Answer: Anti-HBs positive and anti-HBc IgG positive
Correct Answer: HBsAg positive and anti-HBc IgG positive
Explanation:Disease state vs Serology
Acute hepatitis: BHBsAg, HBeAg, anti-HBc IgM
Chronic hepatitis B (low infectivity): HBsAg (>6/12), anti-HBe, anti-HBc IgG
Chronic hepatitis B (high infectivity): HBsAg (>6/12), HBeAg, anti-HBc IgG
Cleared infection: Anti-HBs, anti-HBe, anti-HBc IgG
Vaccinated: Anti-HBs -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 12
Correct
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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 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.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 13
Correct
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Regarding nitrous oxide, which of the following statements is CORRECT:
Your Answer: Nitrous oxide may be used for maintenance of anaesthesia where its use allows reduced dosage of other agents.
Explanation:For anaesthesia, nitrous oxide is commonly used in a concentration of around 50 – 66% in oxygen in association with other inhalation or intravenous agents. Nitrous oxide cannot be used as the sole anaesthetic agent due to lack of potency, but is useful as part of a combination of drugs since it allows reduction in dosage of other agents. Exposure to nitrous oxide for prolonged periods, either by continuous or by intermittent administration, may result in megaloblastic anaemia as a result of interference with the action of vitamin B12. Nitrous oxide increases cerebral blood flow and should be avoided in patients with, or at risk of, raised intracranial pressure. Nitrous oxide may be administered by any trained personnel experienced in its use.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 14
Correct
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Regarding cortical areas, which one is found in the posterior part of the inferior frontal gyrus?
Your 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.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 15
Correct
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By which of the following is mean arterial pressure (MAP) primarily determined?
Your Answer: Total peripheral resistance and cardiac output
Explanation:Mean arterial pressure (MAP) = Cardiac output (CO) x Total peripheral resistance (TPR).
Cardiac output is dependent on the central venous pressure (CVP). CVP, in turn, is highly dependent on the blood volume.
Any alterations of any of these variables will likely change MAP. -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 16
Correct
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Which of the following is NOT an adverse effect associated with statin therapy:
Your Answer: Aplastic anaemia
Explanation:Adverse effects of statins include:, Headache, Epistaxis, Gastrointestinal disorders (such as constipation, flatulence, dyspepsia, nausea, and diarrhoea), Musculoskeletal and connective tissue disorders (such as myalgia, arthralgia, pain in the extremity, muscle spasms, joint swelling, and back pain), Hyperglycaemia and diabetes, Myopathy and rhabdomyolysis, Interstitial lung disease and Hepatotoxicity
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 17
Correct
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A 30-year-old woman is transfused following a diagnosis of anaemia secondary to heavy vaginal bleeding. She complains of feeling hot and cold during transfusion of the second unit and her temperature is 38.5ºC. Prior to the transfusion, her temperature was 37ºC. She has no other symptoms.
Which of these transfusions reactions most likely occurred?Your Answer: Febrile transfusion reaction
Explanation:Febrile transfusion reactions presents with an unexpected temperature rise (≥ 38ºC or ≥ 1ºC above baseline, if baseline ≥ 37ºC) during or shortly after transfusion. It is usually an isolated finding and the fever is accompanied by chills and malaise occasionally.
Allergic reaction is commonly caused by foreign plasma proteins but may be due to anti-IgA. Allergic type reactions usually present with urticaria, pruritus, hives. Associations include laryngeal oedema or bronchospasm.
Acute haemolytic reaction aka immediate haemolytic transfusion reaction presents with fever, chills, pain at transfusion site, nausea, vomiting, dark urine and feeling of ‘impending doom’. Often, it occurs due to ABO incompatibility.
Transfusion-associated circulatory overload (TACO) presents as acute or worsening respiratory distress within 6 hours of transfusion of a large volume of blood. It is common in patients with diminished cardiac reserve or chronic anaemia. Elderly patients, infants and severely anaemic patients are particularly susceptible. Clinical features of TACO include: Acute respiratory distress, Tachycardia, Hypertension, Acute/worsening pulmonary oedema on chest X-ray. The BNP is usually raised to at least 1.5 times the pre-transfusion baseline.
Transfusion-related lung injury (TRALI) is a form of acute respiratory distress caused by the donor plasma containing antibodies against the patient’s leukocytes. It is defined as hypoxia and bilateral pulmonary oedema that occurs within 6 hours of a transfusion in the absence of other causes of acute lung injury. Clinical features include Breathlessness, cough, frothy sputum, hypertension or hypotension, hypoxia and fever. Chest X-ray shows multiple perihilar nodules with infiltration of the lower lung fields.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 18
Correct
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You are instructed by a senior to administer Mannitol to an RTA patient with increased intracranial pressure.
Mannitol is a low molecular weight compound that freely filters at the glomerulus and is not reabsorbed.
Out of the following, which is a contraindication to the use of mannitol?Your Answer: Severe pulmonary oedema
Explanation:Mannitol is the most widely used osmotic diuretic that is most commonly used to reduce cerebral oedema and intracranial pressure.
It is recommended to use mannitol for the reduction of CSF pressure/cerebral oedema in a dose of 0.25-2 g/kg as an intravenous infusion over 30-60 minutes. This can be repeated 1-2 times after 4-8 hours if needed.Mannitol has several contraindications and some of them are listed below:
1. Anuria due to renal disease
2. Acute intracranial bleeding (except during craniotomy)
3. Severe cardiac failure
4. Severe dehydration
5. Severe pulmonary oedema or congestion
6. Known hypersensitivity to mannitol -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 19
Correct
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After collapsing at home, a 75-year-old man is transported in an ambulance. He is now awake, but he is experiencing palpitations and chest pain. He is transported to resuscitation and placed on a cardiac monitor, which indicates that he is in VT. An amiodarone infusion is set up.
Which of the following statements about amiodarone side effects is correct?Your Answer: It can cause jaundice
Explanation:Amiodarone has a lot of potential toxic side effects, so it’s important to get a full clinical evaluation before starting treatment with it.
The following are some of the most common amiodarone side effects:
Arrhythmias
Corneal microdeposits
Hepatic disorders
Hyperthyroidism
Hypothyroidism
Hepatic disorders and jaundice
Nausea
Peripheral neuropathy
Respiratory disorders (including lung fibrosis)
Sleep disturbance
Skin reactions
QT prolongationAmiodarone can cause optic neuritis, which is a very rare side effect. If this happens, the amiodarone should be stopped right away because it poses a risk of blindness.
Most people who take amiodarone develop corneal microdeposits, which go away once the medication is stopped and rarely cause vision problems.
Amiodarone has a chemical structure that is similar to that of thyroxine and can bind to the nuclear thyroid receptor. It can cause both hypothyroidism and hyperthyroidism, though hypothyroidism is far more common, with 5-10% of patients suffering from it.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 20
Correct
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A 45-old woman is on several medications and being treated for epilepsy and bipolar disorder. In the ward rounds, you are asked to examine her in detail and discover she has a noticeable tremor. You believe that one of her medications may be responsible for this new onset tremor.
Which of the following medications is least likely to be responsible for this tremor?Your Answer: Carbamazepine
Explanation:The only medication that does not commonly cause tremors is carbamazepine.
The other drugs present with the following types of tremors as a side effect to their usage:
1. Sodium valproate – Postural tremor is most common, but a resting tremor can also occur. Approximately 25% of patients taking sodium valproate are found to develop a tremor within 12 months of starting therapy.
2. Lithium – fine hand tremor is very commonly seen and reported in as many as 50% of patients during the first week of therapy. The tremor tends to reduce with time and is only present in around 5% of patients taking the medication two years or longer.
3. Atypical antipsychotics, such as olanzapine and quetiapine – tremor and limb shakiness. -
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 21
Correct
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Doxycycline is indicated first line for treatment of which of the following infections:
Your Answer: Chlamydia
Explanation:Doxycycline may be used first line for chlamydia, pelvic inflammatory disease (with metronidazole and ceftriaxone), acute bacterial sinusitis, exacerbation of chronic bronchitis, moderate-severity community acquired pneumonia and high-severity community acquired pneumonia (with benzylpenicillin).
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 22
Correct
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Which of the following microbes adheres to the genital mucosa using fimbriae:
Your Answer: Neisseria gonorrhoeae
Explanation:Infection of the genital mucosa by Neisseria gonorrhoeae involves attachment to and invasion of epithelial cells. Initial adherence of gonococci to columnar epithelial cells is mediated by type IV pili assembled from pilin subunit PilE proteins and pilus tip-associated PilC proteins, it then invades the epithelial layer, triggering a local acute inflammatory response.
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This question is part of the following fields:
- Microbiology
- Principles
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Question 23
Correct
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Achlorhydria is diagnosed in a 37-year-old individual who has had recurring episodes of gastroenteritis. This is an autoimmune illness of the gastric parietal cells that causes insufficient stomach acid production.
Damage to stomach parietal cells will alter the secretion of which other substance?Your Answer: Intrinsic factor
Explanation:Achlorhydria is an autoimmune illness of the gastric parietal cells that causes insufficient stomach acid production. The parietal cells that have been injured are unable to create the necessary amount of stomach acid. As a result, the pH of the stomach rises, food digestion suffers, and the risk of gastroenteritis rises.
The secretion of hydrochloric acid and intrinsic factor is controlled by the gastric parietal cells, which are epithelial cells in the stomach. These cells can be found in the gastric glands, the fundus lining, and the stomach body.
In response to the following three stimuli, the stomach parietal cells release hydrochloric acid:
H2 Histamine receptors are stimulated by histamine (most significant contribution)
Acetylcholine stimulates M3 Receptors via parasympathetic action.
CCK2 receptors are stimulated by Gastrin.Intrinsic factor, which is essential for vitamin B12 absorption, is also produced by stomach parietal cells.
Omeprazole is a proton pump inhibitor that is both selective and irreversible. It inhibits the H+/K+-ATPase system present on the secretory membrane of gastric parietal cells, which lowers stomach acid secretion.
Ranitidine inhibits histamine H2-receptors in a competitive manner. The reversible inhibition of H2-receptors in gastric parietal cells reduces both the volume and concentration of gastric acid. -
This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 24
Correct
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Question 25
Correct
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Which of the following is the site of secretion of intrinsic factor:
Your Answer: Stomach
Explanation:Intrinsic factor is essential for the absorption of the small amounts of vitamin B12 normally present in the diet from the terminal ileum. The parietal cells of the stomach produce intrinsic factor, and following a gastrectomy, the absorption of vitamin B12 will be markedly reduced, and a deficiency state will exist.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 26
Correct
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Which of the following side effects is more common of etomidate than other intravenous induction agents:
Your Answer: Extraneous muscle movements
Explanation:Etomidate is associated with a high incidence of extraneous muscle movements, which can be minimised by an opioid analgesic or a short-acting benzodiazepine given prior to induction. Etomidate causes less hypotension than thiopental sodium and propofol during induction. Etomidate is associated with rapid recovery without a hangover effect. The rate of respiratory depression and tachycardia is not higher in etomidate.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 27
Correct
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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: 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.
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 28
Correct
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An increased anion gap metabolic acidosis is typically caused by which of the following?
Your Answer: Propylene glycol overdose
Explanation:Causes of a raised anion gap acidosis can be remember using the mnemonic MUDPILES:
-Methanol
-Uraemia (in renal failure)
-Diabetic ketoacidosis
-Propylene glycol overdose
-Infection/Iron overdose/Isoniazid/Inborn errors of metabolism
-Lactic acidosis
-Ethylene glycol overdose
-Salicylate overdose -
This question is part of the following fields:
- Physiology
- Renal
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Question 29
Correct
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Which of the following globin chains makes up haemoglobin A2 (HbA2)?
Your 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.
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This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 30
Correct
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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: Glanzamann’s thromboasthenia
Explanation:Glanzmann’s thromboasthenia is a rare platelet disorder in which platelets contain defective or low levels of glycoprotein IIb/IIIa.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 31
Correct
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A 15-year-old male is admitted to a rehabilitation centre with a history of multiple strokes, myopathy and learning disabilities since childhood. He is under the care of a multidisciplinary team, and his genetic testing reports show the presence of a mitochondrial disorder.
Which one of the following diseases does this patient most likely have?Your Answer: MELAS
Explanation:Mitochondrial diseases are a group of disorders caused by dysfunctional mitochondria. Most cases are maternally inherited, as we inherit our mitochondrial DNA from our mothers only, although mutations in nuclear DNA cause some cases.
Examples of Mitochondrial Diseases include:
1. Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS)
2. Mitochondrial epilepsy with ragged red fibres (MERRF)
3. Leber’s hereditary optic neuropathy (LHON)
4. Diabetes mellitus and deafness (DAD)
5. Neuropathy, ataxia, retinitis pigmentosa, and ptosis (NARP)
6. Leigh syndrome (subacute sclerosing encephalopathy).Red-green colour blindness and G6PD deficiency have an X-linked recessive pattern of inheritance.
Tay-Sachs Disease and spinal muscular atrophy have an autosomal recessive pattern of inheritance.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 32
Correct
-
A patient suffers a stab wound to the neck. The entry point of the blade is situated within the posterior triangle of the neck.
Which of the following muscles is LEAST likely to be involved? Select ONE answer only.Your Answer: Sternohyoid
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 nerveThe 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
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Question 33
Correct
-
Which of the following side effects has limited the use of etomidate as an intravenous induction agent:
Your Answer: Adrenocortical suppression
Explanation:Etomidate causes the least cardiovascular depression of the intravenous induction agents, with only a small reduction in the cardiac output and blood pressure. In the past, etomidate was widely used to induce anaesthesia in the shocked, elderly or cardiovascularly unstable patient. However, more recently it has become less popular as a single induction dose blocks the normal stress-induced increase in adrenal cortisol production for 4 – 8 hours, and up to 24 hours in elderly and debilitated patients. Although no increase in mortality has been identified following a single dose during induction of anaesthesia, the use of etomidate has declined due to a perceived potential morbidity.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 34
Incorrect
-
A 32-year-old woman suffers a deep wound to her thigh while she was climbing over a barbed wire fence. As a consequence of her injury, the nerve that was severed innervates the gracilis muscle.
In which of the following nerves is the gracilis muscle innervated by?Your Answer: Posterior branch of the obturator nerve
Correct Answer: Anterior branch of the obturator nerve
Explanation:The gracilis muscles is innervated by the anterior branch of the obturator nerve (L2-L4).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 35
Incorrect
-
Which of the following statements accurately describes the extensor indicis muscle?
Your Answer: It assists with adduction of the hand at the wrist joint
Correct Answer: It lacks the juncturae tendinum
Explanation:Extensor indicis is a narrow, elongated muscle found in the posterior compartment of the forearm. It belongs to the deep extensors of the forearm, together with supinator, abductor pollicis longus, extensor pollicis longus, and extensor pollicis brevis muscles. It lacks the juncturae tendinum, which connects the extensor digitorum on the dorsal aspect of the hand.
Extensor indicis can be palpated by applying deep pressure over the lower part of the ulna while the index finger is extended. The main function of extensor indicis involves the extension of the index finger at the metacarpophalangeal and interphalangeal joints. As the index finger is one of the few fingers that have their own separate extensor muscle, it is able to extend independently from other fingers. Additionally, extensor indicis muscle produces a weak extension of the wrist.
Extensor indicis receives its nervous supply from posterior interosseous nerve, a branch of the radial nerve derived from spinal roots C7 and C8. The skin overlying the muscle is supplied by the same nerve, with fibres that stem from the spinal roots C6 and C7.
The superficial surface of the extensor indicis receives arterial blood supply from posterior interosseous branch of the ulnar artery, whereas its deep surface receives blood from perforating branches of the anterior interosseous artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 36
Incorrect
-
All of the following cause bronchodilation, EXCEPT for:
Your Answer: Adrenaline
Correct Answer: Stimulation of irritant receptors
Explanation:Factors causing bronchodilation: Via beta2-adrenoceptors
Sympathetic stimulation:
Adrenaline (epinephrine)
Beta2-adrenergic agonists e.g. salbutamol
Anticholinergic and muscarinic antagonists e.g. ipratropium -
This question is part of the following fields:
- Physiology
- Respiratory
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Question 37
Correct
-
Which of the following is a clinical effect of hyperkalaemia:
Your 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
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Question 38
Correct
-
A patient with abdominal pain, vomiting and bloody diarrhoea develops a low platelet count and deranged renal function. A diagnosis of haemolytic uraemic syndrome is made.
Which of the following organisms is a recognised cause of haemolytic uraemic syndrome? Select ONE answer only.Your Answer: Escherichia coli
Explanation:E.Colistrain 0157 causes enterohaemorrhagic diarrhoea and can be followed by haemolytic uraemic syndrome (renal failure, haemolytic anaemia and thrombocytopenia).
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 39
Incorrect
-
A patient suffers an injury to the nerve that innervates gluteus medius.​
The gluteus medius muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: Inferior gluteal nerve
Correct Answer: Superior gluteal nerve
Explanation:Gluteus minimus is innervated by the superior gluteal nerve.
Gluteus medius is innervated by the superior gluteal nerve.
Gluteus maximus is innervated by the inferior gluteal nerve. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 40
Correct
-
The patient is a 61-year-old man with severe central chest pain. An acute myocardial infarction is revealed by his ECG. Clopidogrel is one of the medications he takes as part of his treatment.
Clopidogrel's direct mechanism of action is which of the following?Your Answer: Inhibition of platelet ADP receptors
Explanation:Clopidogrel, a thienopyridine derivative, prevents platelet aggregation and cross-linking by the protein fibrin by inhibiting the ADP receptor on platelet cell membranes (inhibits binding of ADP to its platelet receptor (P2Y12 ADP-receptor).
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 41
Correct
-
Which one of the listed cells are typically found in a granuloma?
Your Answer: Epithelioid cells
Explanation:Typically, a granuloma has Langhan’s cells (large multinucleated cells) surrounded by epithelioid cell aggregates, T lymphocytes and fibroblasts.
Antigen presenting monocytic cells are found in the skin are known as Langerhan’s cells.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 42
Incorrect
-
The Auerbach's plexus is a set of ganglia that controls peristalsis and is located in the gut wall.
Auerbach's plexus is located in which layer of the gut wall?Your Answer: Subserosa
Correct Answer: Muscular layer
Explanation:The Auerbach’s plexus, also known as the myenteric plexus, is a collection of ganglia that controls peristalsis and is located in the gut wall.
In the muscular layer of the wall, it is located between the circular and longitudinal muscle layers. It is a linear network of linked neurons that runs the length of the gastrointestinal system. The myenteric plexus generates an increase in gut wall tone and the strength of rhythmical contractions when stimulated.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 43
Correct
-
You review an 83-year-old woman who has stage 5 chronic kidney disease. She has a number of electrolyte problems.
Which ONE of the following decreases the renal reabsorption of phosphate?Your Answer: Parathyroid hormone
Explanation:Parathyroid hormone (PTH) is a polypeptide containing 84 amino acids. It is the principal controller of free calcium in the body.
The main actions of parathyroid hormone 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
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Question 44
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: Loss of sensation over the lateral arm
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).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 45
Correct
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A 17-year-old student presents with a headache and petechial rash. A diagnosis of meningitis was suspected, with a causative agent of Neisseria meningitidis.
Which of the following statements is considered correct regarding Neisseria meningitidis?Your Answer: The antiphagocytic polysaccharide capsule is the main determinant of its pathogenicity
Explanation:N. meningitidis is a Gram-negative cocci and can be found as a commensal as well as an invasive pathogen. It is an important etiologic agent of endemic and epidemic meningitis and meningococcaemia and rarely pneumonia, purulent arthritis, or endophthalmitis. N. meningitidis has also been recovered from urogenital and rectal sites as a result of oral-genital contact. Meningococcal carriage, usually involving nonencapsulated strains, may cause an increase in protective antibody against the pathogenic strains. Of the 12 meningococcal encapsulated serogroups, A, B, C, Y, and W-135 account for most cases of disease in the world. N. meningitidis possesses a polysaccharide capsule that is antiphagocytic and serves as an important virulence factor.
It can be found on the mucosal surfaces of the nasopharynx and oropharynx in 30% of the human population. The organism is transmitted by close contact with respiratory droplet secretions from a carrier to a new host. Only a few newly colonized hosts develop meningococcal disease, with the highest incidence being found in infants and adolescents.
The quadrivalent vaccine Menactra is a polysaccharide-protein conjugated vaccine with antigens to serogroups A, C, Y, and W-135. This conjugate vaccine is licensed for people 2 to 55 years old. This vaccine does not protect against meningitis caused by serogroup B because group B polysaccharide is a very poor immunogen in humans.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 46
Correct
-
A young man develops an infection spread via aerosol transmission.
Which of these organisms is commonly spread by aerosol transmission?Your Answer: Measles virus
Explanation:Aerosols are airborne particles less than 5 µm in size, containing infective organisms that usually cause infection of the upper or lower respiratory tract.
Examples of organisms commonly spread by aerosol transmission are:
Measles virus
Varicella zoster virus
Mycobacterium tuberculosisThe following table summarises the various routes of transmission with example organisms:
Route of transmission
Example organisms
Aerosol (airborne particle < 5 µm)
Mycobacterium tuberculosis
Varicella zoster virus
Measles virusHepatitis A and Rotavirus are spread by the faeco-oral route.
Neisseria gonorrhoea is spread by sexual route.
Staphylococcus aureus is spread by direct contact.
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This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
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Question 47
Correct
-
Regarding Clostridium difficile, which of the following statements is CORRECT:
Your Answer: It is normally found in gut flora.
Explanation:C. difficile is normally found in the gut flora but its growth is normally suppressed by more dominant anaerobes. It has exotoxin-mediated effects causing profuse diarrhoea. Oral clindamycin (a broad spectrum antibiotic) is commonly implicated in precipitating C. difficile colitis; first line treatment is with oral metronidazole. Tetanolysin is a toxin produced by Clostridium tetani bacteria.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 48
Correct
-
You've been summoned to a young man in the resus area who has an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.
The use of adenosine is not contraindicated in which of the following situations?Your Answer: Concurrent use of a beta-blocker
Explanation:The use of a beta-blocker at the same time increases the risk of myocardial depression, but it is not a contraindication.
The use of adenosine is contraindicated in the following situations:
Asthma
COPD (chronic obstructive pulmonary disease)
Decompensated heart failureÂ
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
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Question 49
Correct
-
Regarding antacids, which of the following statements is CORRECT:
Your Answer: Antacids should not be taken at the same time as other drugs as they impair absorption.
Explanation:Antacids should preferably not be taken at the same time as other drugs since they may impair absorption. Antacids act by neutralising stomach acid. They are used for symptomatic relief in dyspepsia, but are not first line for proven peptic ulcer disease where antisecretory drugs have a better healing effect. Magnesium-containing antacids tend to be laxative whereas aluminium-containing antacids tend to be constipating. Antacids are contraindicated in hypophosphataemia.
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This question is part of the following fields:
- Gastrointestinal
- Pharmacology
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Question 50
Correct
-
A 62-year-old female complains of pain in her right upper quadrant. An abdominal ultrasound is conducted, and a big gallstone is discovered. The radiologist who performs the scan speaks with you about the physiology of the gallbladder and biliary tract.
During a 24-hour period, how much bile does the gallbladder produce?
Your Answer: 400-800 ml
Explanation:The gallbladder stores and concentrates bile, which is produced by the liver. In a 24-hour period, around 400 to 800 mL of bile is generated. The breakdown of fats into fatty acids, the removal of waste materials, and cholesterol homeostasis are all crucial functions of bile.
Bile is created on a constant basis, however it is only necessary after a meal has been consumed. The elimination of water and ions concentrates bile in the gallbladder, which is subsequently stored for later use. Food induces the release of the hormone cholecystokinin from the duodenum, the contraction of the gallbladder, and the relaxation of the sphincter of Oddi. The bile then enters the duodenum.
Bile acids have a hydrophobic and hydrophilic area, making them amphipathic. Bile acids’ amphipathic nature allows them to perform the following crucial functions:
Emulsification of lipid aggregates increases the surface area of fat and makes it easier for lipases to digest it.
Lipid solubilization and transport: solubilizes lipids by creating micelles, which are lipid clumps that float in water.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 51
Correct
-
Regarding the glomerular filtration barrier, which of the following statements is CORRECT:
Your Answer: The main factor determining whether a substance is filtered or not is molecular weight.
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.
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This question is part of the following fields:
- Physiology
- Renal
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Question 52
Correct
-
All of the following statement about the microcirculation are correct except:
Your Answer: Over the capillary bed, there is a net absorption of fluid.
Explanation:The hydrostatic pressure along the length of the capillary is usually greater than plasma oncotic pressure. As a result, there is a small net filtration of fluid from the capillary into the interstitial space. The regulation of blood flow into the microcirculation is via the vasoconstriction of small arterioles, which is activated by the sympathetic nervous system through numerous nerve endings in their walls. Unlike proteins, most ions and small molecules diffuse easily across capillary walls and thus the crystalloid osmotic pressure they exert is roughly the same on either side of the capillary wall. Because the plasma colloid osmotic pressure is higher than interstitial colloid osmotic, fluid is drawn intravascularly. A reduction of hydrostatic capillary pressure and transient increase in absorption of fluid is a result of arteriolar constriction.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 53
Correct
-
Regarding fluid balance, which of the following statements is CORRECT:
Your Answer: About three-quarters of extracellular fluid is interstitial.
Explanation:An ‘average’ person (70 kg male) contains about 40 litres of water in total, separated into different fluid compartments by biological semipermeable membranes; plasma cell membranes between extracellular and intracellular fluid, and capillary walls between interstitial and intravascular fluid. Around two-thirds of the total fluid (27 L) is intracellular fluid (ICF) and one-third of this (13 L) is extracellular fluid (ECF). The ECF can be further divided into intravascular fluid (3.5 L) and interstitial fluid (9.5 L).
Transcellular fluid refers to any fluid that does not contribute to any of the main compartments but which are derived from them e.g. gastrointestinal secretions and cerebrospinal fluid, and has a collective volume of approximately 2 L.
Osmosis is the passive movement of water across a semipermeable membrane from regions of low solute concentration to those of higher solute concentration. -
This question is part of the following fields:
- Basic Cellular
- Physiology
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Question 54
Correct
-
A known epileptic is transported in status epilepticus by ambulance. On the way to the hospital, she took some diazepam.
Which of the following statements about diazepam is correct?Your Answer: It crosses into breast milk
Explanation:Diazepam boosts GABA’s effects, giving it sedative, hypnotic, anxiolytic, anticonvulsant, and muscle-relaxing properties. It can be administered orally, rectally, or intravenously.
With a half-life of 20-100 hours, it is a long-acting benzodiazepine. Midazolam, oxazepam, and alprazolam are examples of short-acting benzodiazepines with a half-life of less than 12 hours (Xanax).
If used in the presence of hepatic impairment, benzodiazepines can cause coma. If treatment is necessary, benzodiazepines with shorter half-lives should be used in lower doses. Diazepam is a sedative that crosses into breast milk and should be avoided by breastfeeding mothers.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 55
Correct
-
Which of the following is NOT a contraindication to treatment with aspirin at analgesic doses:
Your Answer: Myasthenia gravis
Explanation:Aspirin (at analgesic doses) is contraindicated in:
People with a history of true hypersensitivity to aspirin or salicylates (symptoms of hypersensitivity to aspirin or salicylates include bronchospasm, urticaria, angioedema, and vasomotor rhinitis)
People with active or previous peptic ulceration
People with haemophilia or another bleeding disorder
Children younger than 16 years of age (risk of Reye’s syndrome)
People with severe cardiac failure
People with severe hepatic impairment
People with severe renal impairmentN.B. Owing to an association with Reye’s syndrome, aspirin-containing preparations should not be given to children under 16 years, unless specifically indicated, e.g. for Kawasaki disease.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 56
Incorrect
-
The following are all examples of type III hypersensitivity EXCEPT for:
Your Answer: Extrinsic allergic alveolitis
Correct Answer: Goodpasture's syndrome
Explanation:Examples of type III reactions include:
Extrinsic allergic alveolitis
Systemic lupus erythematosus (SLE)
Post-streptococcal glomerulonephritis
Reactive arthritis
Rheumatoid arthritis -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 57
Correct
-
A patient diagnosed with cranial nerve palsy exhibits asymmetrical movement of the palate, nasal regurgitation of food, and nasal quality to the voice.
Which of the following cranial nerves is most likely responsible for the aforementioned features?Your Answer: Vagus nerve
Explanation:The vagus nerve, ‘the wanderer’, contains motor fibres (to the palate and vocal cords), sensory components (posterior and floor of external acoustic meatus) and visceral afferent and efferent fibres.
Palatal weakness can cause nasal speech and nasal regurgitation of food. The palate moves asymmetrically when the patient says ‘ahh’. Recurrent nerve palsy results in hoarseness, loss of volume and ‘bovine cough’.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 58
Correct
-
Thyroid cancer has spread to the regional lymph nodes of a patient as seen in a staging CT scan.
The lymph from the thyroid gland will drain directly to which of the following nodes?Your Answer: Deep lateral cervical lymph nodes
Explanation:Lymphatic drainage of the thyroid gland involves the lower deep cervical, prelaryngeal, pretracheal, and paratracheal nodes. The paratracheal and lower deep cervical nodes, specifically, receive lymphatic drainage from the isthmus and the inferior lateral lobes. The superior portions of the thyroid gland drain into the superior pretracheal and cervical nodes.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 59
Correct
-
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: 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.
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This question is part of the following fields:
- Infections
- Microbiology
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Question 60
Correct
-
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: 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.
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This question is part of the following fields:
- Endocrine Pharmacology
- Pharmacology
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Question 61
Correct
-
A 25-year-old athlete suffers an injury to the nerve that innervates the gluteus minimus muscle.
Which of the following nerves innervates the gluteus minimus muscle?Your Answer: Superior gluteal nerve
Explanation:Gluteus minimus is the smallest muscle of the glutei. It is located just beneath the gluteus medius muscle. Gluteus minimus predominantly acts as a hip stabilizer and abductor of the hip.
The superior gluteal nerve innervates the gluteus minimus. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 62
Correct
-
When a person changes from a supine to an upright position, which of the followingcompensatory mechanismsoccurs:
Your Answer: Increased contractility
Explanation:On standing from a prone position, gravity causes blood to pool in veins in the legs. Central venous pressure (CVP) falls, causing a fall in stroke volume and cardiac output (due to Starling’s law) and thus a fall in blood pressure. Normally this fall in BP is rapidly corrected by the baroreceptor reflex which causes venoconstriction (partially restoring CVP), and an increase in heart rate and contractility, so restoring cardiac output and blood pressure. Impaired autonomic nervous activity in the elderly accounts for the greater likelihood of postural hypotension. Any symptoms of dizziness, blurred vision or syncope is due to a transient fall in cerebral perfusion that occurs before cardiac output and mean arterial pressure (MAP) can be corrected.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 63
Incorrect
-
Which of the following best describes the correct administration of adrenaline for a shockable rhythm in adult advanced life support?
Your Answer: Give 0.5 mg of adrenaline after the third shock and every 3 - 5 minutes thereafter
Correct Answer: Give 1 mg of adrenaline after the second shock and every 3 - 5 minutes thereafter
Explanation:Give adrenaline 1 mg IV (IO) (10 mL of 1:10,000 solution) after the 2nd shock for adult patients in cardiac arrest with a shockable rhythm. Repeat adrenaline 1 mg IV (IO) every 3-5 minutes whilst ALS continues.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 64
Correct
-
Herpes simplex virus is transmitted most commonly through which of the following routes:
Your 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.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 65
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
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Question 66
Incorrect
-
Regarding paracetamol, which of the following statements is CORRECT:
Your Answer: It has anti-inflammatory action.
Correct Answer: It has anti-pyretic action.
Explanation:Paracetamol is a non-opioid analgesic, similar in efficacy to aspirin, with antipyretic properties but no anti-inflammatory properties. It is well absorbed orally and does not cause gastric irritation. Paracetamol is a suitable first-line choice for most people with mild-to-moderate pain, and for combination therapy.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 67
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 onlyHeparin 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 machinesThere 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.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 68
Incorrect
-
A foot drop is a sign of damage to which of the following nerves?
Your Answer: Tibial nerve
Correct Answer: Deep fibular nerve
Explanation:The deep fibular nerve was previously referred to as the anterior tibial nerve.
It starts at the common fibular nerve bifurcation, between the fibula and the proximal part of the fibularis longus. Damage to this nerve can cause foot drop or loss of dorsiflexion since this nerve controls the anterior leg muscles.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 69
Correct
-
Which of the following statements about neutrophils is TRUE:
Your Answer: Neutrophils are typically the first immune cell to arrive to a site of injury.
Explanation:Neutrophils are the most numerous peripheral blood leukocytes, accounting for 50-70 percent of all circulating white cells. Neutrophils have a compact nucleus with two to five lobes and a pale cytoplasm with an irregular shape containing numerous fine pink-blue or grey-blue granules. The granules are classified as primary, which emerges during the promyelocyte stage, and secondary, which develop at the myelocyte stage and predominate in the mature nucleus.
The lifespan of neutrophils in the blood is only 6 – 10 hours. In response to tissue damage, cytokines and complement proteins, neutrophils migrate from the bloodstream to the site of insult within minutes, where they destroy pathogens by phagocytosis.
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This question is part of the following fields:
- Immune Responses
- Pathology
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Question 70
Correct
-
A 42-year-old woman presents with face swelling prominently affecting her upper lip and hands. She has previously been diagnosed with hereditary angioedema.
Which of these is the most appropriate management option for this acute attack?Your Answer: Fresh frozen plasma
Explanation:Hereditary angioedema is inherited as an autosomal dominant disorder and is caused by deficiency of C1 esterase inhibitor, a protein that forms part of the complement system.
Attacks can be precipitated by stress and minor surgical procedures. Clinical features of hereditary angioedema include oedema of the skin and mucous membranes commonly affecting the face, tongue and extremities.
Angioedema and anaphylaxis due to a deficiency of C1 esterase inhibitor are resistant to adrenaline, steroids and antihistamines. Treatment is with fresh frozen plasma or C1 esterase inhibitor concentrate, which contains C1 esterase inhibitor.
Short-term prophylaxis for events that may precipitate angioedema attack is achieved with C1 esterase inhibitor or fresh frozen plasma infusions before the event while long-term prophylaxis can be achieved with antifibrinolytic drugs (tranexamic acid) or androgenic steroids.
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This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 71
Correct
-
After a work-related accident, a 33-year old male is taken to the emergency room with difficulty in adduction and flexion of his left arm at the glenohumeral joint. The attending physician is suspects involvement of the coracobrachialis muscle.
The nerve injured in the case above is?Your Answer: The musculocutaneous nerve
Explanation:The coracobrachialis muscle is innervated by the musculocutaneous nerve (C5-C7) a branch of the lateral cord of the brachial plexus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 72
Correct
-
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: 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
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Question 73
Incorrect
-
Stimulation of J receptors located on alveolar and bronchial walls results in all of the following EXCEPT for:
Your Answer: Relaxation of skeletal muscle
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.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 74
Correct
-
Regarding fat digestion, which of the following statements is CORRECT:
Your 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.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 75
Incorrect
-
Loop diuretics primarily act on which Na+ transporter?
Your Answer: Na + /K + ATPase pump
Correct Answer: Na + /K + /2Cl - symporter
Explanation:The most potent diuretics are loop diuretics e.g. furosemide. They work by inhibiting the Na+/K+/2Cl-symporter in the thick ascending limb of the loop of Henle, which inhibits sodium, potassium, and chloride reabsorption. As a result, there is diuresis with loss of these electrolytes. There is a reduction in transcellular voltage difference, paracellular calcium and magnesium reabsorption.
The medullary interstitium becomes more concentrated by salt reabsorption in the ascending limb. Loop diuretics block this process and reduce the ability of the kidney to concentrate urine. In the collecting duct, there is increased sodium delivery to the principal cells, which increases potassium secretion in return for sodium reabsorption. -
This question is part of the following fields:
- Physiology
- Renal
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Question 76
Incorrect
-
Aldin is a 24-year-old male patient who arrives at the emergency department diagnosed with psittacosis based on his symptoms and history of being a pigeon enthusiast. Which of the following is the causative bacteria of psittacosis?
Your Answer: Chlamydia pneumoniae
Correct Answer: Chlamydia psittaci
Explanation:Chlamydia psittaci is a microorganism that is commonly found in birds.
These bacteria can infect people and cause psittacosis. Psittacosis is an infectious disease that may cause high fever and pneumonia associated with headaches, altered mental state, and hepatosplenomegaly.
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This question is part of the following fields:
- Infections
- Microbiology
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Question 77
Incorrect
-
Which of the following causes the first heart sound?
Your Answer: Opening of the atrioventricular valves
Correct Answer: Closing of the atrioventricular valves
Explanation:The heart sounds are as a result of the various parts of the cardiac cycle.
Heart Sound – Phase of Cardiac Cycle – Mechanical Event:
1st heart sound – Systole starts – there is closure of the atrioventricular (mitral & tricuspid) valves
2nd heart sound – Systole ends – there is closure of the semilunar (aortic and pulmonary) valves
3rd heart sound – Early diastole – this is caused by rapid flow of blood from the atria into the ventricles during the ventricular filling phase
4th heart sound – Late diastole – this is caused by filling of an abnormally stiff ventricle in atrial systole -
This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 78
Correct
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Question 79
Incorrect
-
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: Temporal lobe
Correct 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.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 80
Incorrect
-
Regarding iron deficiency anaemia, which of the following statements is INCORRECT:
Your Answer: Iron deficiency is associated with koilonychia and atrophic glossitis.
Correct Answer: Dietary insufficiency is the most common cause of iron deficiency anaemia in adult men in the UK.
Explanation:Blood loss from the gastrointestinal (GI) tract is the most common cause of iron deficiency anaemia in adult men and postmenopausal women.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 81
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 othersAntibiotic 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
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Question 82
Incorrect
-
Regarding likelihood ratios, which of the following statements is INCORRECT:
Your Answer: Positive likelihood ratio = sensitivity/(1 - specificity)
Correct Answer: Likelihood ratios, like predictive values, are affected by the prevalence of the disease in the population.
Explanation:A likelihood ratio is a measure of the diagnostic value of a test. Likelihood ratios show how many times more likely patients with a disease are to have a particular test result than patients without the disease. Likelihood ratios are more useful than predictive values because they are calculated from sensitivity and specificity and therefore remain constant even when the prevalence of the disorder changes.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 83
Incorrect
-
Which coronary artery is mostly likely affected if an ECG shows a tombstone pattern in leads V2, V3 and V4?
Your Answer: Left marginal artery
Correct Answer: Left anterior descending artery
Explanation:Tombstoning ST elevation myocardial infarction can be described as a STEMI characterized by tombstoning ST-segment elevation. This myocardial infarction is associated with extensive myocardial damage, reduced left ventricle function, serious hospital complications and poor prognosis. Tombstoning ECG pattern is a notion beyond morphological difference and is associated with more serious clinical results.
Studies have shown that tombstoning is more commonly found in anterior than non-anterior STEMI, thus, higher rates of left anterior descending artery disease are observed in patients with tombstoning pattern.
The following ECG leads determine the location and vessels involved in myocardial infarction:
ECG Leads Location Vessel involved
V1-V2 Septal wall Left anterior descending
V3-V4 Anterior wall Left anterior descending
V5-V6 Lateral wall Left circumflex artery
II, III, aVF Inferior wall Right coronary artery (80%) or Left circumflex artery (20%)
I, aVL High lateral wall Left circumflex artery
V1, V4R Right ventricle Right coronary artery
V7-V9 Posterior wall Right coronary artery -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 84
Correct
-
A 59-year-old woman presents with a history of tiredness and weight gain and a diagnosis of hypothyroidism is suspected.
Which of these changes is likely to appear first in primary hypothyroidism?Your Answer: Increased thyroid-stimulating hormone (TSH)
Explanation:The earliest biochemical change seen in hypothyroidism is an increase in thyroid-stimulating hormone (TSH) levels.
Triiodothyronine (T3) and thyroxine (T4) levels are normal in the early stages.
TBG levels are generally unchanged in primary hypothyroidism.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 85
Incorrect
-
Which of the following is an example of continuous data:
Your Answer: Gender
Correct Answer: Height
Explanation:Continuous data is data where there is no limitation on the numerical value that the variable can take e.g. weight, height.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 86
Correct
-
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: 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
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Question 87
Incorrect
-
A 40-year-old man with episodes of blood in urine and flank pain that are recurrent presents for management. He has a history of hypertension that is difficult to control and recurrent urinary tract infections. Other findings are: bilateral masses in his flanks and haematuria (3+ on dipstick).
What is the most likely diagnosis?Your Answer: Nephronophthisis
Correct Answer: Polycystic kidney disease
Explanation:Autosomal dominant polycystic kidney disease (ADPKD) presents with abdominal or loin discomfort due to the increasing size of the kidneys, acute loin pain with or without haematuria, hypertension, and male infertility. It is the most common cause of serious renal disease and the most common inherited cause of renal failure in adults.
Alport syndrome has hearing loss and eye abnormalities in addition to symptoms of kidney disease.
Renal cell carcinoma presents with additional features of unexplained weight loss, loss of appetite, fever of unknown origin and anaemia.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 88
Incorrect
-
Gastrin release from antral G-cells is inhibited by all but which one of the following:
Your Answer: Low gastric pH
Correct Answer: Vagal stimulation
Explanation:Gastrin secretion is inhibited by:
Low gastric pH (negative feedback mechanism)
Somatostatin
Secretin
Gastric inhibitory polypeptide (GIP)
Cholecystokinin -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 89
Incorrect
-
C-reactive protein (CRP) synthesis is predominantly stimulated by which of the following cytokines:
Your Answer: IL-5
Correct Answer: IL-6
Explanation:Activated leukocytes, adipocytes, and endothelial cells all release interleukin 6 (IL-6), a significant proinflammatory cytokine. The main downstream mediator of the acute phase response is C-reactive protein, which is predominantly produced by IL-6–dependent hepatic biosynthesis.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 90
Incorrect
-
An analytical cohort study aimed to determine a relationship between intake of dietary calcium and incidence of hip fractures among post-menopausal women. The following are the data obtained from the study:
No. of post-menopausal women who took Calcium: 500
No. of post-menopausal women who took Calcium and suffered a hip fracture: 10
No. of post-menopausal women who took placebo: 500
No. of post-menopausal women who took placebo and suffered a hip fracture: 25
Compute for the absolute risk in the placebo group.Your Answer: 0.1
Correct Answer: 0.05
Explanation:The absolute risk (AR) is the probability or chance of an event. It is computed as the number of events in treated or control groups, divided by the number of people in that group.
AR = 25/500 = 0.05
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This question is part of the following fields:
- Evidence Based Medicine
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Question 91
Incorrect
-
You received a patient with a 2-day history of diarrhoea and vomiting. Later, after examination, the patient was found to have progressive symmetric descending flaccid paralysis, initial development of blurred vision, dysphagia, and weakness of the upper limbs. The patient is apyrexial and his observations are all normal. Which of the following pathogens is responsible for the said symptoms?
Your Answer: Clostridium tetani
Correct Answer: Clostridium botulinum
Explanation:A botulism infection results in neuroparalysis caused by the neurotoxin generated by Clostridium botulinum.
Food-borne botulism symptoms often appear 12-36 hours after ingestion of the toxin-containing food and may include nausea, vomiting, stomach discomfort, and diarrhoea at first. The most common neurological pattern is an acute onset of bilateral cranial neuropathies with symmetric declining weakening.
Other distinguishing characteristics include the absence of fever, the absence of cognitive abnormalities, the presence of a normal heart rate and blood pressure, and the absence of sensory defects.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 92
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: Skin biopsy
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.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 93
Incorrect
-
Regarding bile, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Bile passes into the duodenum through the ampulla of Vater.
Explanation:Bile is synthesised in the liver. Bile functions to eliminate endogenous and exogenous substances from the liver, to neutralise gastric acid in the small intestine, and to emulsify fats in the small intestine and facilitate their digestion and absorption. Bile is stored and concentrated in the gallbladder. Bile passes out of the gallbladder via the cystic duct. Bile passes into the duodenum through the ampulla of Vater regulated by the sphincter of Oddi.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 94
Incorrect
-
What is the effect of a positive inotrope on the Starling curve:
Your Answer:
Correct Answer: Shifts the curve upwards
Explanation:Contractility (inotropy) is the intrinsic ability of cardiac muscle to develop force at a given muscle length. It is determined by the intracellular [Ca2+] and can be estimated by the ejection fraction. Increases in contractility cause an increase in stroke volume/cardiac output for any level of right atrial pressure or end-diastolic volume, and hence shift the Starling curve upwards. Decreases in contractility cause a decrease in stroke volume/cardiac output for any level of right atrial pressure or end-diastolic volume and hence shift the Starling curve downwards.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 95
Incorrect
-
You're evaluating a male patient who's having a lung function test done. In calculating the patient’s functional residual capacity, what parameters should you add to derive the functional residual capacity volume?
Your Answer:
Correct Answer: Expiratory reserve volume + residual volume
Explanation:The volume of air that remains in the lungs after a single breath is known as functional residual capacity (FRC). It is calculated by combining the expiratory reserve volume and residual volume.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 96
Incorrect
-
Which of the following is the primary indication for loop diuretics?
Your Answer:
Correct Answer: Acute pulmonary oedema
Explanation:Loop diuretics have long been the cornerstone of pulmonary oedema treatment, with furosemide being the most commonly used of these drugs. Premedication with drugs that decrease preload (e.g., nitro-glycerine [NTG]) and afterload (e.g., angiotensin-converting enzyme [ACE] inhibitors) before the administration of loop diuretics can prevent adverse hemodynamic changes.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 97
Incorrect
-
A CT pulmonary angiography of a patient with a massive pulmonary embolus will most likely show which of the following signs?
Your Answer:
Correct Answer: Increased alveolar dead space
Explanation:A CT pulmonary angiogram is an angiogram of the blood vessels of the lungs. It is a diagnostic imaging test used to check for pulmonary embolism.
A pulmonary embolism is caused by a blood clot or thrombus that has become lodged in an artery in the lung and blocks blood flow to the lung. A patient with pulmonary embolism may feel an abrupt onset of pleuritic chest pain, shortness of breath, and hypoxia. Also, pulmonary embolism can result in alveolar dead space.
Dead space represents the volume of ventilated air that does not participate in gas exchange. The alveolar dead space is caused by ventilation/perfusion imbalances in the alveoli. It is defined as the sum of the volumes of alveoli that are ventilated but not perfused.
Aside from pulmonary embolism, smoking, bronchitis, emphysema, and asthma are among the other causes of alveolar dead space.
The other types of dead space are the following: Anatomical dead space is the portion of the airways that conducts gas to the alveoli. This is usually around 150 mL, and there is no possibility of gas exchange in these areas. Physiological dead space is the sum of anatomical and alveolar dead spaces.
Physiological dead space can account for up to 30% of the tidal volume.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 98
Incorrect
-
Which of the following is NOT a notifiable disease:
Your Answer:
Correct Answer: HIV
Explanation:HIV mainly infects CD4+ T helper cells. Viral replication results in progressive T-cell depletion and impaired cell-mediated immunity with subsequent secondary opportunistic infections and increased risk of malignancy. B-cell function is also reduced as a result of lack of T-cell stimulation.
HIV is not a notifiable disease. -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 99
Incorrect
-
Which of these statements about the monospot test is true?
Your Answer:
Correct Answer: It can be positive in rubella
Explanation:Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety of unrelated non-EBV heterophile antibodies.
Heterophile antibodies:
About 70-90% of patients with EBV infectious mononucleosis produce antibodies against an antigen produced in one species that react against antigens from other species called heterophile antibodies. False positives can be seen with rubella, hepatitis, SLE, malaria, toxoplasmosis, lymphoma and leukaemia.These antibodies can be detected by two main screening tests:
The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.
Paul-Bunnell test uses sheep red blood cells. The blood agglutinates in the presence of heterophile antibodies.EBV-specific antibodies:
Patients can remain heterophile-negative after six weeks and are then considered to be heterophile-negative and should be tested for EBV-specific antibodies. EBV-specific antibodies test are helpful if a false positive heterophile antibody test is suspected.
The indirect Coombs test is used to detect in-vitro antibody-antigen reactions. It is typically used in antenatal antibody screening and in preparation for blood transfusion.
Heterophile antibody tests are generally not positive in the incubation period of infectious mononucleosis (4-6 weeks) before the onset of symptoms. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 100
Incorrect
-
Renal potassium excretion is promoted by all but which one of the following:
Your Answer:
Correct Answer: Increased intracellular magnesium
Explanation:Aldosterone: A rise in [K+] in the extracellular fluid of the adrenal cortex directly stimulates aldosterone release. Aldosterone promotes the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane, and also stimulates apical sodium and potassium channel activity, overall acting to increase sodium reabsorption and potassium secretion.
pH changes: Potassium secretion is reduced in acute acidosis and increased in acute alkalosis. A higher pH increases the apical K+channel activity and the basolateral Na+/K+ATPase activity – both changes that promote K+secretion.
Flow rates: Increased flow rates in the collecting duct reduce K+concentration in the lumen and therefore enhance K+secretion. Increased flow also activates BK potassium channels, and ENaC channels which promote potassium secretion and sodium reabsorption respectively.
Sodium delivery: Decreased Na+delivery to the collecting ducts results in less Na+reabsorption and hence a reduced gradient for K+secretion.
Magnesium: Intracellular magnesium can bind and block K+channels inhibiting K+secretion into the tubules. Therefore magnesium deficiency reduces this inhibitory effect and so allows more potassium to be secreted into tubules and can cause hypokalaemia. -
This question is part of the following fields:
- Physiology
- Renal
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SESSION STATS - PERFORMANCE PER SPECIALTY
