Medical Technologist Test Hematology 2 — Questions and Answers
Question 1: What is the anticoagulant of choice for a complete blood count (CBC) specimen?
- Sodium citrate
- EDTA (Correct answer)
- Heparin
- Oxalate
Correct answer: EDTA
EDTA (lavender top tube) chelates calcium to prevent clotting and best preserves cell morphology for CBC analysis.
Question 2: Schistocytes on a peripheral blood smear are associated with which condition?
- Polycythemia vera
- Microangiopathic hemolytic anemia (Correct answer)
- Chronic lymphocytic leukemia
- Iron deficiency anemia
Correct answer: Microangiopathic hemolytic anemia
Schistocytes (fragmented red cells) result from mechanical destruction of RBCs seen in TTP, HUS, and DIC.
Question 3: Which coagulation test is used to monitor heparin therapy?
- PT/INR
- aPTT (Correct answer)
- Thrombin time
- Bleeding time
Correct answer: aPTT
The activated partial thromboplastin time (aPTT) monitors the intrinsic pathway and is used to adjust unfractionated heparin dosing.
Question 4: A patient with polycythemia vera would be expected to have which laboratory result?
- Decreased hematocrit
- Elevated erythropoietin level
- Increased red cell mass with low erythropoietin (Correct answer)
- Thrombocytopenia
Correct answer: Increased red cell mass with low erythropoietin
Polycythemia vera is a myeloproliferative disorder with increased RBC mass and suppressed erythropoietin due to autonomous bone marrow production.
Question 5: Which cell is the precursor to platelets in the bone marrow?
- Myeloblast
- Megakaryocyte (Correct answer)
- Erythroblast
- Monoblast
Correct answer: Megakaryocyte
Megakaryocytes undergo cytoplasmic fragmentation (thrombopoiesis) to release platelets into the bloodstream.
Question 6: Rouleaux formation on a peripheral smear is commonly associated with which condition?
- Sickle cell disease
- Multiple myeloma (Correct answer)
- G6PD deficiency
- Hemophilia A
Correct answer: Multiple myeloma
Rouleaux (stacked coin-like RBC arrangement) occurs when elevated proteins like immunoglobulins reduce the negative charge between RBCs, common in multiple myeloma.
Medical Technologist Test Hematology 2
What is the anticoagulant of choice for a complete blood count (CBC) specimen?