Master Blood Transfusion MCQs: Coagulation & Hematology – 30 MCQs | Kenya MBChB

30 Year 3: Blood Transfusion exam questions on Master Blood Transfusion MCQs: Coagulation & Hematology for medical students. Includes MCQs, answers, explanation

This MCQ set contains 30 questions on Master Blood Transfusion MCQs: Coagulation & Hematology in the Year 3: Blood Transfusion unit. Each question includes the correct answer and a detailed explanation for active recall and exam preparation.

Q1: Which coagulation factor is deficient in Hemophilia A?

  1. A. Factor VIII
  2. B. Factor IX
  3. C. Factor XI
  4. D. Factor XIII

Correct answer: A – Factor VIII

Hemophilia A = Factor VIII deficiency; Hemophilia B = Factor IX deficiency (Christmas disease).

Q2: Most common cause of prolonged PT with normal aPTT?

  1. A. Von Willebrand disease
  2. B. Factor VII deficiency
  3. C. Lupus anticoagulant
  4. D. Heparin therapy

Correct answer: B – Factor VII deficiency

Factor VII is only in the extrinsic pathway (measured by PT); its deficiency prolongs PT while leaving aPTT normal.

Q3: PT 45s, aPTT 65s (both prolonged) — most likely cause?

  1. A. Warfarin overdose
  2. B. DIC
  3. C. Liver disease
  4. D. Factor V deficiency

Correct answer: C – Liver disease

Liver disease impairs synthesis of multiple coagulation factors, prolonging both pathways.

Q4: Blood product for thrombocytopenia with active bleeding?

  1. A. FFP
  2. B. Packed RBCs
  3. C. Cryoprecipitate
  4. D. Platelet concentrate

Correct answer: D – Platelet concentrate

Thrombocytopenia = low platelets; replacing platelets directly addresses the bleeding cause.

Q5: The crossmatch test primarily detects?

  1. A. All of the above
  2. B. Rh incompatibility
  3. C. Irregular antibodies
  4. D. ABO incompatibility

Correct answer: A – All of the above

The crossmatch detects any antibody-antigen reaction between donor RBCs and recipient serum.

Q6: Emergency transfusion, blood type unknown — give?

  1. A. AB positive RBCs
  2. B. O negative RBCs
  3. C. AB positive FFP
  4. D. O positive RBCs

Correct answer: B – O negative RBCs

O negative is the universal donor — no A, B, or Rh antigens to trigger reactions.

Q7: Cryoprecipitate contains high concentrations of all EXCEPT?

  1. A. Fibrinogen
  2. B. Factor VIII
  3. C. Von Willebrand factor
  4. D. Factor IX

Correct answer: D – Factor IX

Cryo contains: fibrinogen, Factor VIII, Factor XIII, vWF, and fibronectin. Factor IX is NOT in cryoprecipitate.

Q8: Positive direct antiglobulin test (DAT) indicates?

  1. A. Antibodies in patient's serum
  2. B. Antibodies bound to patient's RBCs
  3. C. ABO incompatibility
  4. D. Hemolytic transfusion reaction

Correct answer: B – Antibodies bound to patient's RBCs

DAT detects IgG or complement already coating the patient's own RBCs in vivo.

Q9: Most serious immediate complication of blood transfusion?

  1. A. Febrile non-hemolytic reaction
  2. B. Allergic reaction
  3. C. Acute hemolytic reaction
  4. D. TACO

Correct answer: C – Acute hemolytic reaction

ABO-incompatible transfusion causes massive intravascular hemolysis, DIC, renal failure — rapidly fatal.

Q10: Most sensitive lab test for detecting DIC?

  1. A. Platelet count
  2. B. Fibrinogen level
  3. C. PT/aPTT
  4. D. D-dimer

Correct answer: D – D-dimer

D-dimer is highly sensitive for DIC — elevated whenever clot formation and lysis are simultaneously occurring.

Q11: Von Willebrand disease is characterized by?

  1. A. Prolonged PT only
  2. B. Prolonged aPTT only
  3. C. Prolonged bleeding time and aPTT
  4. D. Prolonged PT and aPTT

Correct answer: C – Prolonged bleeding time and aPTT

vWF is needed for platelet adhesion (bleeding time) and carries Factor VIII (aPTT).

Q12: Mechanism of action of warfarin?

  1. A. Direct thrombin inhibition
  2. B. Factor Xa inhibition
  3. C. Platelet aggregation inhibition
  4. D. Vitamin K antagonism

Correct answer: D – Vitamin K antagonism

Warfarin inhibits Vitamin K epoxide reductase, blocking activation of factors II, VII, IX, and X.

Q13: Patient on heparin — monitored using?

  1. A. PT/INR
  2. B. aPTT
  3. C. Bleeding time
  4. D. Platelet count

Correct answer: B – aPTT

Heparin potentiates antithrombin III; therapeutic target is 1.5–2.5× normal aPTT.

Q14: Heparin-induced thrombocytopenia (HIT) typically occurs?

  1. A. Within 24 hours
  2. B. After 3 weeks
  3. C. 5–10 days after starting heparin
  4. D. Only with high-dose heparin

Correct answer: C – 5–10 days after starting heparin

HIT is immune-mediated via antibodies against heparin-PF4 complexes.

Q15: Most important blood group system after ABO and Rh?

  1. A. Kell
  2. B. Duffy
  3. C. Kidd
  4. D. MNS

Correct answer: A – Kell

Kell antigens are highly immunogenic and clinically the next most significant after ABO and Rh.

Q16: Massive transfusion is defined as?

  1. A. 50% volume in 12h
  2. B. 100% volume in 24h
  3. C. 150% volume in 24h
  4. D. 10 units

Correct answer: B – 100% volume in 24h

Replacement of the entire blood volume (~5L) within 24 hours, or 10 units of RBCs.

Q17: FFP:Platelets:RBCs ratio in massive transfusion protocol?

  1. A. 1:1:1
  2. B. 1:1:2
  3. C. 1:2:3
  4. D. 1:1:4

Correct answer: A – 1:1:1

Evidence-based damage control resuscitation uses a balanced 1:1:1 ratio.

Q18: Antithrombin III deficiency predisposes to?

  1. A. Bleeding disorders
  2. B. Thrombotic disorders
  3. C. Platelet dysfunction
  4. D. Hemolytic anemia

Correct answer: B – Thrombotic disorders

ATIII is a natural anticoagulant; its deficiency causes thrombophilia.

Q19: Most common inherited bleeding disorder?

  1. A. Hemophilia A
  2. B. Hemophilia B
  3. C. Von Willebrand disease
  4. D. Factor V Leiden

Correct answer: C – Von Willebrand disease

vWD affects ~1% of the population — the most common inherited bleeding disorder worldwide.

Q20: Factor V Leiden mutation causes?

  1. A. Bleeding tendency
  2. B. Resistance to activated protein C
  3. C. Warfarin resistance
  4. D. Heparin resistance

Correct answer: B – Resistance to activated protein C

Factor V Leiden makes Factor Va resistant to cleavage by activated Protein C, causing thrombophilia.

Q21: TRALI is most commonly caused by?

  1. A. Bacterial contamination
  2. B. Volume overload
  3. C. Donor antibodies against recipient leukocytes
  4. D. ABO incompatibility

Correct answer: C – Donor antibodies against recipient leukocytes

Donor anti-HLA or anti-HNA antibodies activate recipient neutrophils in the lung, causing non-cardiogenic pulmonary edema within 6 hours.

Q22: Shelf life of platelet concentrates at room temperature?

  1. A. 3 days
  2. B. 5 days
  3. C. 7 days
  4. D. 14 days

Correct answer: B – 5 days

Stored at 20–24°C with agitation; limited to 5 days due to bacterial contamination risk.

Q23: Which factor is NOT part of the intrinsic coagulation pathway?

  1. A. Factor VIII
  2. B. Factor IX
  3. C. Factor VII
  4. D. Factor XII

Correct answer: C – Factor VII

Factor VII belongs exclusively to the extrinsic pathway. Intrinsic: XII, XI, IX, VIII.

Q24: Protein S functions as a cofactor for?

  1. A. Protein C
  2. B. Antithrombin III
  3. C. Factor V
  4. D. Factor VIII

Correct answer: A – Protein C

Protein S enhances activated Protein C's ability to degrade Factors Va and VIIIa.

Q25: Most common cause of acquired coagulation disorder?

  1. A. Vitamin K deficiency
  2. B. Liver disease
  3. C. DIC
  4. D. Medication-induced

Correct answer: B – Liver disease

The liver synthesizes nearly all coagulation factors — liver disease is the most common acquired coagulopathy globally.

View on OmpathStudy