ABO Discrepancies and Subgroups Flashcards
Unexpected reactions in Forward or Reverse blood grouping
ABO discrepancies
Identify the group of ABO discrepancies.
- Weakly reacting or missing reactions in reverse typing
- Weakly reacting antibodies
Group 1
Identify the group of ABO discrepancies.
- Weakly reacting or missing reactions in forward typing
- Weakly reacting or missing antigens
- Least frequently encountered
Group 2
Identify the group of ABO discrepancies.
- Psuedoagglutination or rouleaux formation in RT and FT
Group 3
Identify the group of ABO discrepancies.
- Miscellaneous problems between FT and RT
Group 4
Identify the group of ABO discrepancies.
- depression of antigens in leukemia and Hodgkin’s disease
- subgroups of A and B
- acquired phenomenon
- chimerism
Group 2
Identify the group of ABO discrepancies.
- protein or plasma abnormalities
- Rouleaux formation / pseudoagglutination
- wharton’s jelly
- ↑ globulin or fibrinogen
Group 3
Identify the group of ABO discrepancies.
- Cold reactive autoantibodies
- Circulating RBCs of more than one ABO group
- Unexpected ABO isoagglutinins
- Unexpected non-ABO alloantibodies
- Cis-AB
Group 4
What phenotype of the A subgroup contains A and A1 antigens (react with both antibodies)?
A1 cell
What phenotype of the A subgroup contains A antigens only (react with anti-A only)?
A2 cell
What reagent agglutinates both A2 and A1 cells?
Anti-A antisera
What reagent agglutinates only A1 cells and is used to distinguish A subgroups?
Dolichos biflorus
What reagent will you treat RBCs for the resolution of group 2 discrepancies?
acetyl anhydride
What is the resolution of group 3 discrepancies?
washing red cells with saline several times (6-8 times for cord blood studies)
What reagent will you treat the forward test used for group 4 discrepancies?
dithiothreitol (DTT)
