MLPAO Transfusion Medicine Advanced Practice Flashcards

What is gel column technology (gel test) and how does it work in blood banking?

Answer: A method using dextran gel-filled microtubes where agglutinated red cells are trapped in the gel while non-agglutinated cells pass through to the bottom

Gel column technology (DiaMed/Bio-Rad) uses microtubes containing dextran acrylamide gel. After incubation, tubes are centrifuged: agglutinated red cells are trapped in the gel matrix (positive result), while non-agglutinated cells pass through to the bottom (negative result). This standardized method reduces subjective interpretation and is widely used for typing, antibody screening, and crossmatching.

What is transfusion-related acute lung injury (TRALI)?

Answer: Acute respiratory distress occurring within 6 hours of transfusion, caused by donor antibodies activating recipient neutrophils in pulmonary capillaries

TRALI is a serious complication characterized by acute bilateral pulmonary edema and hypoxia within 6 hours of transfusion, without other risk factors for acute lung injury. It is caused by donor anti-HLA or anti-HNA antibodies that activate recipient neutrophils in pulmonary capillaries. Risk reduction strategies include using male-only plasma donors.

What is the significance of the Duffy blood group system in relation to malaria?

Answer: The Duffy antigen Fy(a)/Fy(b) serves as the receptor for Plasmodium vivax; Duffy-negative individuals are resistant to P. vivax malaria

The Duffy glycoprotein (DARC) serves as the receptor for P. vivax merozoite invasion of red blood cells. The Fy(a-b-) phenotype (common in individuals of West African descent due to a GATA-1 binding site mutation) confers resistance to P. vivax malaria. This selective advantage has maintained the high frequency of the Duffy-null phenotype in malaria-endemic regions.

What is the role of Canadian Blood Services (CBS) in the Canadian blood system?

Answer: CBS is responsible for collecting, testing, processing, and distributing blood and blood products across Canada (except Québec, which is served by Héma-Québec)

Canadian Blood Services (CBS) is the national, not-for-profit blood operator responsible for the collection, testing, processing, and distribution of blood and blood products for all Canadian provinces and territories except Québec (served by Héma-Québec). CBS also manages the national stem cell, organ, and tissue donation programs.

What infectious disease testing is performed on all donated blood in Canada?

Answer: HIV, Hepatitis B, Hepatitis C, HTLV-I/II, Syphilis, West Nile Virus, and additional tests as required

All Canadian blood donations are tested for: HIV-1/2 (antibody and NAT), Hepatitis B (HBsAg, anti-HBc, NAT), Hepatitis C (antibody and NAT), HTLV-I/II (antibody), Syphilis (antibody), and West Nile Virus (NAT). Additional testing (e.g., Babesia, Zika) may be implemented based on risk assessment. Nucleic acid testing (NAT) has significantly narrowed the window period.

What is the difference between leukoreduction and irradiation of blood products?

Answer: Leukoreduction removes white blood cells to prevent febrile reactions, CMV transmission, and HLA alloimmunization; irradiation inactivates residual lymphocytes to prevent TA-GVHD

Leukoreduction (filtration to <5 × 10⁶ residual WBCs) prevents febrile non-hemolytic transfusion reactions, CMV transmission, and HLA alloimmunization. In Canada, all red cells and platelets are pre-storage leukoreduced. Irradiation (25 Gy gamma) inactivates residual T lymphocytes to prevent TA-GVHD in susceptible patients. They serve different, complementary purposes.