CLT CLT Hematology & Blood Analysis 3

Question 1

Which condition is characterized by the presence of Howell-Jolly bodies on a peripheral blood smear?

Accepted Answer

Sickle cell disease or post-splenectomy

Answer

Howell-Jolly bodies are nuclear remnants in RBCs normally removed by the spleen; their presence indicates asplenia or splenic dysfunction.

Question 2

What is the principle behind the automated cell counter's impedance method for counting blood cells?

Accepted Answer

Cells disrupt electrical current as they pass through an aperture

Answer

In the impedance (Coulter) method, cells passing through a small aperture disrupt an electrical current, and the magnitude of the change correlates with cell size and count.

Question 3

A patient presents with a prolonged aPTT but a normal PT. Which coagulation factor deficiency is most consistent with this result?

Accepted Answer

Factor VIII (Hemophilia A)

Answer

Factor VIII deficiency (Hemophilia A) prolongs the aPTT, which tests the intrinsic pathway, while the PT (extrinsic pathway) remains normal.

Question 4

Hypersegmented neutrophils (>5 lobes) on a blood smear are a classic finding in which type of anemia?

Accepted Answer

Megaloblastic anemia (B12 or folate deficiency)

Answer

Hypersegmented neutrophils are characteristic of megaloblastic anemia caused by vitamin B12 or folate deficiency, which impairs DNA synthesis.

Question 5

Which parameter in a CBC directly reflects the variation in red blood cell size?

Accepted Answer

RDW (Red Cell Distribution Width)

Answer

RDW measures the degree of anisocytosis (variation in RBC size); an elevated RDW suggests a heterogeneous population of red cells.

(CLT) Clinical Laboratory Technologist Certification Practice Test

(CLT) Clinical Laboratory Technologist Certification Practice Test

CLT CLT Hematology & Blood Analysis 3