8 clinical MCQs in Blood Transfusion. A 62-year-old female presents with mucosal bleeding and a platelet count of 950,000/µL. Bo
Q1. A 62-year-old female presents with mucosal bleeding and a platelet count of 950,000/µL. Bone marrow biopsy shows clusters of large, mature megakaryocytes with 'staghorn' nuclei. Molecular testing is positive for CALR mutation. What is the primary risk factor for transformation to myelofibrosis?
Answer: Presence of ASXL1 or EZH2 mutations
Explanation: ASXL1 and EZH2 are epigenetic modifier mutations that drive disease progression in Essential Thrombocythemia toward myelofibrosis, independent of platelet count or age.
Q2. A 28-year-old female at 32 weeks gestation presents with schistocytic anemia, thrombocytopenia, and normal coagulation studies. ADAMTS13 is 45%. BP is 160/110 mmHg, urinalysis shows 3+ protein. What is the most likely diagnosis?
Answer: HELLP Syndrome
Explanation: HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) is confirmed by the pregnancy context, hypertension, and proteinuria. ADAMTS13 10% rules out TTP. Normal coagulation rules out DIC.
Q3. A 19-year-old male presents with massive lymphadenopathy. Biopsy shows 'starry sky' appearance. IHC positive for CD19, CD20, CD10, BCL-6, negative for BCL-2. Cytogenetics show t(8;14). Which metabolic complication is he at highest risk for during induction therapy?
Answer: Tumor Lysis Syndrome with Hyperkalemia
Explanation: This is Burkitt Lymphoma (t(8;14), starry sky, BCL-2 negative). Its extremely high proliferation rate causes massive Tumor Lysis Syndrome upon treatment — releasing potassium, phosphate, and uric acid into the bloodstream.
Q4. A 70-year-old male with Waldenström Macroglobulinemia presents with sudden vision loss and epistaxis. Fundoscopy shows 'sausage-link' retinal veins. Serum viscosity is 4.5 centipoise. What is the immediate treatment?
Answer: Emergent Plasmapheresis
Explanation: Hyperviscosity syndrome is a medical emergency. Plasmapheresis rapidly removes the excess IgM paraprotein, immediately reducing serum viscosity and reversing symptoms. Rituximab is used later for disease control.
Q5. A 45-year-old male with fatigue, splenomegaly, WBC 120,000/µL, full myeloid spectrum on smear with basophilia, and t(9;22). Which molecular finding is most associated with the accelerated phase?
Answer: Additional trisomy 8 or second Ph chromosome
Explanation: This is CML. Clonal evolution — acquiring additional chromosomal abnormalities like trisomy 8 or a second Philadelphia chromosome — signals progression to the accelerated phase, indicating loss of disease control.
Q6. A patient with WAIHA requires a transfusion. The antibody screen is pan-reactive. Which technique is most appropriate to identify underlying clinically significant alloantibodies?
Answer: Differential allogeneic adsorption
Explanation: When autoantibodies mask alloantibodies, allogeneic adsorption using cells of different phenotypes (R1R1, R2R2, rr) removes the autoantibody while preserving detectable alloantibodies for identification.
Q7. Four hours after a platelet transfusion, a patient develops chills, 2°C fever rise, respiratory distress, BP 80/40 mmHg, bilateral infiltrates on CXR, and low PCWP. What is the most likely cause?
Answer: Transfusion Related Acute Lung Injury (TRALI)
Explanation: TRALI presents with acute hypoxia, bilateral infiltrates, and low PCWP (ruling out cardiogenic cause). It occurs within 6 hours of transfusion and is caused by donor anti-HLA/HNA antibodies activating recipient neutrophils in the lungs.
Q8. A neonate with HDFN due to anti-D requires exchange transfusion. Mother is O negative, infant is A positive. What is the best blood product?
Answer: O negative RBCs reconstituted with AB plasma
Explanation: O negative RBCs avoid both maternal anti-D (D-negative) and ABO incompatibility. AB plasma is used because it contains no anti-A or anti-B, making it safe for any infant ABO type.