ASCP Hematology 3

Question 1

Disseminated intravascular coagulation (DIC) is best characterized by:

Accepted Answer

Prolonged PT/PTT, low fibrinogen, elevated D-dimer

Answer

DIC causes simultaneous clotting and fibrinolysis, resulting in prolonged coagulation times, consumed fibrinogen, and elevated D-dimer.

Question 2

Which automated hematology parameter best distinguishes iron deficiency anemia from beta-thalassemia minor?

Accepted Answer

RDW and Mentzer Index

Answer

The Mentzer Index (MCV/RBC) <13 suggests thalassemia; >13 suggests iron deficiency, and elevated RDW favors iron deficiency.

Question 3

The osmotic fragility test is used to diagnose which condition?

Accepted Answer

Hereditary spherocytosis

Answer

Hereditary spherocytosis shows increased osmotic fragility because spherocytes lyse more readily in hypotonic solutions.

Question 4

Which coagulation factor is tested by the prothrombin time (PT)?

Accepted Answer

Factor VII

Answer

PT measures the extrinsic and common pathways, with Factor VII being the extrinsic pathway factor most sensitive to PT changes.

Question 5

Auer rods are pathognomonic for which type of leukemia?

Accepted Answer

Acute myeloid leukemia

Answer

Auer rods are fused lysosomes seen only in myeloid blasts, making them diagnostic of acute myeloid leukemia.

ASCP Practice Test