Blood banking

A patient's cells react 4+ with Anti-A and 0 with Anti-B. The serum reacts 1+ with A cells and 4+ with B cells. What is the most likely cause of this discrepancy?

Subgroup of A

Which antibody systems show dosage?

Rh, Kidd, Duffy, MNS

A patient experiences hypotension, fever, and bilateral pulmonary edema shortly after transfusion. The donor unit contains HLA antibodies. What is the diagnosis?

TRALI

Treating reagent red cells with proteolytic enzymes like ficin or papain will enhance the reactivity of which antibody?

Anti-Rh

A patient with a history of severe febrile non-hemolytic transfusion reactions should receive which type of blood component?

Leukocyte-reduced RBCs

A patient's serum reacts with all screening cells at room temperature (IS), but the autocontrol is negative. What is the most likely cause?

Cold alloantibody (anti-Le^a or anti-P1)

What is the primary mechanism of action of Rh Immune Globulin (RhIg)?

Clearing of foetal D+ cells

A patient with a delayed hemolytic transfusion reaction (DHTR) likely exhibits which laboratory finding?

Positive DAT with anti-IgG

A donor unit is labeled 'CMV Negative'. This unit is most indicated for which patient group?

Low birth weight infants

Which of the following is an effect of proteolytic enzymes on the Duffy blood group system?

Antigens are destroyed

What is the clinical significance of a low-titer, cold-reactive antibody identified as Anti-I?

Generally clinically insignificant

When performing a crossmatch, what is the primary purpose of the 'Immediate Spin' phase?

Detection of ABO incompatibility

Which structural feature is unique to both pentameric $IgM$ and dimeric $IgA$ that allows for their polymerization?

J-Chain

A technologist observes 'mixed-field' agglutination during ABO forward grouping. Which condition is the most likely cause?

Subgroup A3

To prevent Transfusion-Associated Graft-vs-Host Disease (TA-GVHD), which modification must be performed on blood components?

Gamma irradiation

An antibody panel shows reactions that are destroyed by treatment with Ficin. Which of the following antibodies is likely present?

Duffy or MNS

Which blood group system is most commonly associated with delayed hemolytic transfusion reactions (DHTR) due to titers that drop below detectable levels?

Kidd

Kleihauer-Betke test calculation part 1:

Foetal RBC % = (faetal cells/ total red cells) x 100

Kleihauer-Betke test calculation part 2:

Foetal blood volume = Foetal RBC % x 50

Kleihauer-Betke test calculation part 3:

Number of vials = (foetal blood volume / 30) round + 1

A patient with no history of transfusion or pregnancy has a positive antibody screen. The panel shows a pattern consistent with anti-Le^a. What is the clinical significance of this antibody for crossmatching?

clinically insignificant

What is the primary purpose of adding 'check cells' (Coombs Control Cells) to all negative antiglobulin tests?

To confirm AHG was added and active

Which condition is characterized by a positive Direct Antiglobulin Test (DAT) with a 'broad-spectrum' AHG but a negative antibody screen?

Warm autoimmune haemolytic anemia

Which reagent is used to distinguish between $IgM$ and $IgG$ antibodies by cleaving the disulfide bonds of the $IgM$ pentamer?

DDT

A patient has a suspected $anti-I$. Which technique is best used to determine if there are underlying clinically significant alloantibodies?

Pre-warmed technique