Haematology End of Year 2025 Past Paper — OmpathStudy

MOUNT KENYA UNIVERSITY — UNIVERSITY EXAMINATION 2024/2025 School of Medicine, Department of Pathology BMBS Year 3 Unit: MBML 3200 — Haematology Date: 14th July 2025, 2:00PM Duration: 2hrs 30mins Paper One — Section A: 60 MCQs (60 marks) Section B: 7 SAQs (60 marks) Section C: 1 LAQ (20 marks) SECTION A: MCQs 1. A 28-year-old woman presents with fatigue and pallor. CBC shows low haemoglobin and peripheral blood film shows microcytic hypochromic red blood cells. What is the most likely diagnosis? a) Vitamin B12 deficiency b) Iron deficiency anaemia c) Aplastic anaemia d) Haemolytic anaemia e) Sickle cell anaemia Answer: b) Iron deficiency anaemia Explanation: Iron deficiency impairs haem synthesis, producing small, pale RBCs. 2. The primary site of haematopoiesis in adults is: a) Liver b) Spleen c) Bone marrow d) Lymph nodes e) Thymus Answer: c) Bone marrow Explanation: Adult active marrow is confined mainly to the axial skeleton. 3. Which blood cell type is primarily responsible for defence against parasitic infections? a) Neutrophils b) Basophils c) Eosinophils d) Monocytes e) Lymphocytes Answer: c) Eosinophils Explanation: Release major basic protein and cationic protein, cytotoxic to helminths. 4. Which clotting factor is deficient in Haemophilia A? a) Factor V b) Factor VII c) Factor VIII d) Factor IX e) Factor X Answer: c) Factor VIII Explanation: X-linked recessive deficiency affecting the intrinsic pathway. 5. A patient presents with recurrent infections, petechiae, and anaemia. Bone marrow biopsy shows reduced cellularity. What is the most likely diagnosis? a) Iron deficiency anaemia b) Sickle cell disease c) Polycythaemia vera d) Aplastic anaemia e) Thalassaemia Answer: d) Aplastic anaemia Explanation: Marrow failure causes pancytopenia (infections, bleeding, anaemia). 6. Haemopoiesis is the process of: a) Blood clot formation b) White blood cell destruction c) Blood cell production d) Plasma protein synthesis e) Iron transport Answer: c) Blood cell production Explanation: Formation of all blood cellular components from stem cells. 7. A 62-year-old man presents with fatigue, fever and bruising. FBC shows WCC 40x10^9/L with 25% circulating blasts, Hb 90 g/L, platelets 50x10^9/L. Which investigation is required to definitively diagnose acute myeloid leukaemia? a) Bone marrow aspirate and trephine biopsy b) Peripheral blood smear c) Flow cytometry of peripheral blood d) Computed tomography scan e) Serum lactate dehydrogenase Answer: a) Bone marrow aspirate and trephine biopsy Explanation: Gives definitive blast count, morphology, cytochemistry, immunophenotyping and cytogenetics. 8. Which cytochemical stain is most useful to confirm lymphoblasts in suspected ALL? a) Myeloperoxidase (MPO) b) Terminal deoxynucleotidyl transferase (TdT) c) Sudan Black B d) Tartrate-resistant acid phosphatase (TRAP) e) Periodic acid-Schiff (PAS) Answer: b) TdT Explanation: Nuclear enzyme expressed in immature lymphoid precursors, absent in mature cells. 9. A patient receiving chemotherapy shows a drop in neutrophil count. This condition is termed: a) Anaemia b) Leukocytosis c) Neutropenia d) Thrombocytopenia e) Erythrocytosis Answer: c) Neutropenia Explanation: Chemotherapy is myelosuppressive, lowering absolute neutrophil count. 10. Which chromosomal translocation is pathognomonic of chronic myeloid leukaemia? a) t(8;21) b) t(15;17) c) t(9;22)(q34;q11) d) t(4;11) e) inv(16) Answer: c) t(9;22)(q34;q11) Explanation: Philadelphia chromosome; BCR-ABL fusion leads to constitutive tyrosine kinase activity. 11. Thrombopoietin primarily regulates the production of: a) Red blood cells b) Plasma cells c) Platelets d) Monocytes e) Eosinophils Answer: c) Platelets Explanation: Stimulates megakaryocyte proliferation and maturation. 12. Which of the following is a stem cell marker used to identify haematopoietic stem cells? a) CD3 b) CD4 c) CD19 d) CD34 e) CD20 Answer: d) CD34 Explanation: Standard marker for haematopoietic progenitor/stem cells. 13. In a bone marrow biopsy of a patient with aplastic anaemia, you would expect to find: a) Hypercellular marrow with many erythroblasts b) Increased megakaryocytes c) Fatty replacement and hypocellularity d) Increased lymphoid follicles e) Excessive neutrophil precursors Answer: c) Fatty replacement and hypocellularity Explanation: Haematopoietic tissue is replaced by fat, reducing cellularity. 14. Granulocyte colony-stimulating factor (G-CSF) is used clinically to: a) Increase platelet production b) Stimulate lymphocyte activation c) Promote neutrophil recovery after chemotherapy d) Inhibit erythropoiesis e) Enhance clotting factor production Answer: c) Promote neutrophil recovery after chemotherapy Explanation: Stimulates granulocyte precursor proliferation, shortening neutropenia. 15. A patient with Chronic Lymphoid Leukaemia develops a warm autoimmune haemolytic anaemia. Which test is essential to confirm this complication? a) Direct antiglobulin (Coombs) test b) Indirect antiglobulin te