Medical Laboratory Technician Exam Blood Bank and Transfusion 5

Question 1

Which blood group system is associated with the receptor for Plasmodium vivax malaria?

Accepted Answer

Duffy (Fy)

Answer

The Duffy antigen (DARC) is the receptor for P. vivax merozoites; Fy(a-b-) individuals, common in West Africa, are resistant to P. vivax malaria.

Question 2

A technologist performing an elution notices the eluate reacts with all panel cells. The MOST likely cause is:

Accepted Answer

A warm autoantibody coating the red cells

Answer

A panreactive eluate is classic for warm autoimmune hemolytic anemia (WAIHA), where autoantibody eluted from the patient's cells reacts with all test cells.

Question 3

According to AABB Standards, the minimum hemoglobin content in a unit of packed red blood cells must be at least:

Accepted Answer

51 g per unit

Answer

AABB Standards require ≥51 g of hemoglobin per RBC unit (≥80% of units tested) to ensure adequate therapeutic content.

Question 4

Which blood group antibody is classically associated with paroxysmal cold hemoglobinuria (PCH)?

Accepted Answer

Anti-P (Donath-Landsteiner antibody)

Answer

PCH is caused by the Donath-Landsteiner biphasic antibody, which has anti-P specificity, binding complement at cold temperatures and causing hemolysis upon warming.

Question 5

Massive transfusion is generally defined as transfusion of:

Accepted Answer

10 or more units of RBCs within 24 hours (or one blood volume)

Answer

Massive transfusion is defined as replacement of one entire blood volume (approximately 10 units of RBCs) within 24 hours in an adult.

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Blood Bank and Transfusion 5