Medical Laboratory TechnicianĀ Exam FREE Medical Laboratory Technician Hematology and Coagulation Questions and Answers 2 ā Questions and Answers
Question 1: A patient's CBC reveals an MCV of 110 fL and oval macrocytes on the peripheral smear. Which nutrient deficiency is most likely responsible?
- Vitamin B12 or folate (Correct answer)
- Iron
- Vitamin C
- Zinc
Correct answer: Vitamin B12 or folate
Oval macrocytes with elevated MCV are characteristic of megaloblastic anemia caused by vitamin B12 or folate deficiency.
Question 2: Which coagulation factor is measured exclusively by the prothrombin time (PT) and not the activated partial thromboplastin time (aPTT)?
- Factor VII (Correct answer)
- Factor X
- Factor V
- Factor II
Correct answer: Factor VII
Factor VII is unique to the extrinsic pathway and is evaluated only by the PT.
Question 3: A D-dimer test is most useful in ruling out which condition?
- Deep vein thrombosis (Correct answer)
- Hemophilia A
- Iron deficiency anemia
- Polycythemia vera
Correct answer: Deep vein thrombosis
A negative D-dimer has high sensitivity for excluding deep vein thrombosis and pulmonary embolism.
Question 4: What is the expected finding on a peripheral blood smear in a patient with disseminated intravascular coagulation (DIC)?
- Schistocytes (Correct answer)
- Spherocytes
- Target cells
- Howell-Jolly bodies
Correct answer: Schistocytes
Schistocytes (fragmented red blood cells) result from mechanical shearing of RBCs through fibrin strands in DIC.
Question 5: Which anticoagulant is preferred for routine coagulation testing such as PT and aPTT?
- 3.2% sodium citrate (Correct answer)
- EDTA
- Sodium heparin
- Potassium oxalate
Correct answer: 3.2% sodium citrate
Sodium citrate at 3.2% concentration is the standard anticoagulant for coagulation studies because it reversibly binds calcium.
Question 6: A prolonged bleeding time with a normal platelet count and normal PT/aPTT most likely suggests which condition?
- von Willebrand disease (Correct answer)
- Factor V Leiden
- Hemophilia B
- Antithrombin III deficiency
Correct answer: von Willebrand disease
Von Willebrand disease causes prolonged bleeding time due to defective platelet adhesion despite normal platelet counts.
A patient's CBC reveals an MCV of 110 fL and oval macrocytes on the peripheral smear.
Which nutrient deficiency is most likely responsible?