Transfusion with blood products carries a risk of acute and more chronic adverse reactions. These reactions can either be immune mediated due to a component mismatch, or non immune, underpinned by bacterial or viral contamination. Reactions range from very mild such as urticaria, to life threatening in the case of transfusion-related acute lung injury. In transfusion with packed red blood cells, the most common adverse event is pyrexia, while urticaria is the most common adverse event that follows infusion with FFP.

From the options mentioned here, the closest diagnosis is haemophilia. This is a mixed picture, as a purpuric rash on the buttocks does not correlate with this diagnosis. However, the most appropriate diagnosis is haemophilia.

The age of the patient and the presence of immature white blood cells are suggestive of leukaemia. Hodgkin’s disease is unlikely in this age group and it usually presents with lymphadenopathy. In HIV, immature white blood cells are not present in the blood.

The presentation of the child is highly suggestive of Henoch-Schonlein purpura (HSP). It is an IgA-mediated, autoimmune hypersensitivity vasculitis that targets the small vessels of the skin, GI tract, kidneys, and joints.It is most commonly seen in children aged 3 – 6 years old and is twice as common in boys than girls. Preceding viral URTI with low-grade pyrexia is common. The most common organism associated with HSP is, however, Group A streptococcal infection.A purpuric rash is seen on the back of the legs and buttocks and can less frequently affect the arms. Arthralgia is common (usually knees/ankles) in these patients.Abdominal pain and bloody diarrhoea may occur. And half of the children with HSP have renal involvement. Rarely, it can lead to end-stage renal failure.Treatment includes adequate hydration, occasionally steroids, and other immunosuppressants. The disease can recur in 1 in 3 children.

Breast milk jaundice is a type of jaundice associated with breast-feeding. It typically occurs one week after birth. The condition can sometimes last up to 12 weeks, but it rarely causes complications in healthy, breast-fed infants. The exact cause of breast milk jaundice isn’t known. However, it may be linked to a substance in the breast milk that prevents certain proteins in the infant’s liver from breaking down bilirubin. The condition may also run in families. Breast milk jaundice is rare, affecting less than 3 percent of infants. When it does occur, it usually doesn’t cause any problems and eventually goes away on its own. It’s safe to continue breast-feeding.

Red blood cells (RBC) have a life span of 120 days in humans.Aging of RBC includes changes in many properties: decreased metabolic activity, morphological alterations, including decreased cell volume and changes in cell shape, and quantitative and qualitative modulations of the surface.

Due to breakdown of the red blood cell membrane in haemophilic patients, cholesterol crystals are formed by the lipids. On the other hand lipofuscin deposition does not occur in haemolysis or haemorrhage. Neutrophil accumulation suggests acute inflammation. Anthracotic pigment is an exogenous carbon pigment that deposits in the lung from dust. Russell bodies are intracellular accumulations of immunoglobins in plasma cells. Curschmann’s spirals and Charcot Leyden crystals are pathognomonic of asthma.

Acute lymphoblastic leukaemia (ALL) is an aggressive type of blood and bone marrow cancer which can appear in childhood. Signs of childhood ALL include: Fever, Easy bruising, Petechiae, Bone or joint pain, Painless lumps in multiple areas of the body, Weakness, fatigue or paleness, and Loss of appetite. Blood tests may show elevated white blood cells, decreased values of red blood cells and low platelet count.

Howell-Jolly bodies are often seen in post-splenectomy cases, together with Pappenheimer bodies, target cells and irregular contracted red blood cells. The loss of splenic tissue results in the inability to readily remove immature or abnormal red blood cells from the circulation.

Haemophilia A and haemophilia B are inherited in an X-linked recessive pattern. The genes associated with these conditions are located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition.

In haemophilia C, The severity of the deficiency is based on plasma factor XIC (clotting) activity. Major factor XI deficiency is present when the activity of factor XI in plasma is less than 1-15 IU/dL.In major deficiency factor XI, bleeding is related to injury, especially when trauma involves tissues rich in fibrinolytic activators, such as the oral mucosa, the nose, and the urinary tract. Unlike patients with severe haemophilia A or B, patients with major factor XI deficiency do not spontaneously bleed.The aPTT is usually prolonged in factor XI deficiency (but depends on the sensitivity of the reagent and test system–partial deficiency can be missed), whereas the PT and TT are normal.

Hassall’s corpuscles are groups of epithelial cells within the thymic medulla. The physical nature of these structures differs between mammalian species. Although Hassall’s corpuscles have been proposed to act in both the removal of apoptotic thymocytes and the maturation of developing thymocytes within the thymus, the function of Hassall’s corpuscles has remained an enigma.

Hyposplenism usually occurs after the surgical removal of the spleen or in pathological processes where the splenic tissue is replaced with abnormal tissue. It is often associated with diseases such as sickle cell disease, Coeliac disease, SLE and Dermatitis Herpetiformis. Myxoedema however bears no known association with hyposplenism. Patients with hyposplenism are at risk of fulminant bacterial infection.

Haemophilia B (also known as Christmas disease) is due to a deficiency in factor IX. Haemophilia A is due to a deficiency in factor VIII.

Carbon monoxide is a colourless gas, which is toxic to animals. It has a high affinity for haemoglobin (around 250 times greater than oxygen). It combines with haemoglobin forming carboxyhaemoglobin, which decreases the oxygen-carrying capacity of the blood, leading to a left-shift in the oxygen-dissociation curve. CO is produced endogenously in limited amounts (0.4ml per hour), but the toxic levels are higher.

The clinical features and the presentation of this child and the MRI findings are highly suggestive of acute lymphoblastic leukaemia.Anaemia and neutropenia, with a borderline platelet count as well as the tumour infiltration on both femurs on the MRI scan, are suggestive of a widespread Marrow disorder. Based on the age of the patient, acute lymphoblastic leukaemia is more appropriate as it is more common than acute myeloid leukaemia in children and can present with bony pain in this age group.Other options:- Acute myeloid leukaemia: Although this is the most common leukaemia that is seen in adults, it rarely presents in children. – Ewing’s sarcoma: This would usually present in a more unilateral manner, and would only be associated with cytopenia if there was direct bone marrow involvement.- HIV infection: It would be very rare in this group. HIV infection can cause a wide array of signs and symptoms, but we are told that the MRI scan is highly suggestive of tumour infiltration, which would be uncommon in this condition. – Juvenile arthritis: It is much less common. There is also nothing to find on examination, such as swollen or painful joints, which would usually be seen in this condition.

Blood tests do not help in the diagnosis of jaundice except of course by telling the level of jaundice (bilirubin) and providing some corroborative evidence such as autoantibodies, tumour markers or viral titres in the case of hepatitis. Classifying causes of jaundice on the basis of ultrasound provides a quick and easy schema for diagnosing jaundice which is applicable in primary care as well as hospital based practice.

Due to breakdown of the red blood cell membrane in haemophilic patients, cholesterol crystals are formed by the lipids. On the other hand lipofuscin deposition does not occur in haemolysis or haemorrhage. Neutrophil accumulation suggests acute inflammation. Anthracotic pigment is an exogenous carbon pigment that deposits in the lung from dust. Russell bodies are intracellular accumulations of immunoglobins in plasma cells. Curschmann’s spirals and Charcot Leyden crystals are pathognomonic of asthma.

The anti-B antibodies in a patient with blood group A belong to the IgM class of immunoglobulins.Note:IgM is the largest antibody formed of 5 antibodies attached together. This functions to agglutinate or clump antigens. The associated anti-A and anti-B antibodies are usually IgM produced in the first years of life by sensitisation to environmental substances such as food, bacteria, and viruses.Other options:- IgG is the most common antibody. It is a single antibody complex.- IgD is found on the surface of B-lymphocytes.- IgE is bound to tissue cells, especially mast cells and eosinophils.

The differentials of the child’s condition are likely to include an Iron deficiency anaemia, or a hemoglobinopathy such as sickle cell disease or thalassemia based on the presentation of pallor, growth failure and easy fatiguability. While the full blood count and film present a hypochromic microcytic anaemia with reticulocytosis, the normal serum ferritin levels rule out iron deficiency anaemia. Thalassemia is to be suspected over sickle cell disease as the patient comes from the Mediterranean region known for a high incidence of thalassemia. Sickle cell anaemia also tends to present with normocytic normochromic red blood cells, with many sickled cells. Vitamin B12 deficiency and Aplastic anaemia are ruled out as they present with a macrocytic anaemia, and a decrease in white blood cells, platelets and red blood cells respectively.

This history is suggestive of Henoch-Schönlein Purpura following a respiratory infection. A typical rash involving thighs and buttocks is often seen in this age group. Coagulation profile is the suitable answer from the given answers.

A peripheral blood film in iron deficiency anaemia can reveal the following morphologically variant RBCs:- Microcytic cells- Hypochromic cells- Pencil cells- Target cellsOther options:- Schistocytes can be caused by mechanical heart valves. – Rouleaux can be seen in chronic liver disease and malignant lymphoma. – Tear-drop poikilocytes can be seen in myelofibrosis. – Acanthocytes can be seen in liver disease and McLeod blood group phenotype.Pathological red cell forms include:- Target cells: Sickle-cell/thalassaemia, iron-deficiency anaemia, hyposplenism, and liver disease.- Tear-drop poikilocytes: Myelofibrosis- Spherocytes: Hereditary spherocytosis and autoimmune haemolytic anaemia- Basophilic stippling: Lead poisoning, thalassaemia, sideroblastic anaemia, and myelodysplasia- Howell-Jolly bodies: Hyposplenism- Heinz bodies: G6PD deficiency and alpha-thalassaemiaSchistocytes (‘helmet cells’): Intravascular haemolysis, mechanical heart valve, and disseminated intravascular coagulation- Pencil poikilocytes: Iron deficiency anaemia- Burr cells (echinocytes): Uraemia and pyruvate kinase deficiency – Acanthocytes: Abetalipoproteinemia

Factors V and VIII are consumed most rapidly in a patient with disseminated intravascular coagulation.Simultaneous coagulation and haemorrhage caused by initially formation of thrombi which consume clotting factors (factors 5,8) and platelets, ultimately leading to bleeding.Causes include:- Infection- Malignancy- Trauma e.g. major surgery, burns, shock, dissecting aortic aneurysm- Liver disease- Obstetric complicationsClinically bleeding is usually a dominant feature, bruising, ischaemia and organ failure.Blood tests reveal prolonged clotting times, thrombocytopenia, decreased fibrinogen and increased fibrinogen degradation products.Treatment of DIC involves treating the underlying cause and supportive management.Mnemonic:D-I-S-S-E-M-I-N-A-T-E-DD- D dimerI-Immune complexesS-Snakebite, shock, heatstrokeS-SLEE-Eclampsia, HELLP syndromeM-Massive tissue damageI-Infections: viral and bacterialN-NeoplasmsA-Acute promyelocytic leukaemiaT-Tumour products: Tissue Factor (TF) and TF-like factors released by carcinomas of pancreas, prostate, lung,colon, stomachE-Endotoxins (bacterial)D-Dead foetus (retained)

Jaundice is considered pathologic if it presents within the first 24 hours after birth. Although up to 60 percent of term new-borns have clinical jaundice in the first week of life, few have significant underlying disease.1,2 However, hyperbilirubinemia in the new-born period can be associated with severe illnesses such as haemolytic disease, metabolic and endocrine disorders, anatomic abnormalities of the liver, and infections. The risk factors here is the mothers blood ground which suggests the cause is fetal-maternal blood group incompatibility.

Aplastic anaemia causes a deficiency of all blood cell types: red blood cells, white blood cells, and platelets. It is more frequent in people in their teens and twenties, but is also common among the elderly. It can be caused by heredity, immune disease, or exposure to chemicals, drugs, or radiation. However, in about one-half of cases, the cause is unknown.The definitive diagnosis is by bone marrow biopsy| normal bone marrow has 30–70% blood stem cells, but in aplastic anaemia, these cells are mostly gone and replaced by fat.First-line treatment for aplastic anaemia consists of immunosuppressive drugs, typically either anti-lymphocyte globulin or anti-thymocyte globulin, combined with corticosteroids, chemotherapy and ciclosporin. Hematopoietic stem cell transplantation is also used, especially for patients under 30 years of age with a related matched marrow donor.

The most probable diagnosis based on the scenario provided above is hereditary spherocytosis.While jaundice and abdominal pain might make you think of hepatitis or cholecystitis in the first instance, the lack of fever suggests otherwise. The apyrexial presentation is against acute cholecystitis, and the past medical history reveals a chronic type of fatigue and two previous episodes of hepatitis. Furthermore, it is unlikely that the child has contracted infective hepatitis twice and now a third time! The most common cause of hepatitis in childhood is hepatitis A, however the lack of travel history to endemic areas makes this less likely. Hepatitis A is usually a mild, self-limiting disease that never presents with chronic symptoms. The chronicity of his fatigue and the blood results lead towards a haematological diagnosis. This is further substantiated by his low haemoglobin levels, high MCV and high reticulocyte count. Chronic haemolytic anaemia is the most likely cause, and the negative Coombs excludes autoimmune haemolytic anaemia (AIHA). Thus, leaving us with the answer as hereditary spherocytosis.Hereditary spherocytosis is a disorder that makes the cytoskeleton of red cells more fragile and therefore leads to red cell death and splenomegaly. Gallstones are a result of this red cell destruction and increased haem metabolism.

Hematopoietic stem cells (HSCs) are a rare population of cells residing in the bone marrow (BM) and continuously replenish all mature blood cells throughout their life span.

The child is suffering from acute sickle cell crisis, a complication of sickle cell disease. It is characterised by a new segmental pulmonary infiltrate consistent with consolidation together with one or more new respiratory symptoms.The mainstay of treatment is oxygen support, (ventilation if required), hydration, antibiotics and analgesia.

Based on the studies, genetic factors are responsible for approximately 60 % DVT cases. Factor V (FV) Leiden which is the most common cause of inherited thrombophilia, predisposes patients to DVT because of resistance to protein C.The heritable causes of deep vein thrombosis, from most to least common are:Factor V LeidenProthrombin G20210A variantProtein C deficiencyProtein S deficiencyAntithrombin deficiencyVon Willebrand disease and thalassaemia are not causes of DVT.

Consuming iron in its Fe2+ (ferrous form) form can improve the ability to absorb dietary iron in patients with iron deficiency anaemia (IDA). Clinical features of IDA include:- Koilonychia- Atrophic glossitis- Post-cricoid webs- Angular stomatitisThe peripheral blood smear shows the following abnormal RBC morphologies:- Target cells- Pencil poikilocytes- Microcytic-hypochromic cells