Blood Bank

Question 1

ABO discrepancy: Forward Group has weak or absent reaction

Answer 1

Sub-group of A (transfuse w/ O), Transfused with Group O (check Hx), Newborn <6mon or elderly patient, Weakened expression due to leukaemia (check Hx), Excessive A or B substance, or Bone Marrow transplant (check Hx)

Question 2

ABO discrepancy: Forward has Unexpected Positive Reaction

Answer 2

Acquired B antigen due to carcinoma of colon or rectum, Polyagglutination due to T activation (transfuse O cells), or Bone marrow transplant (check Hx)

Question 3

ABO discrepancy: Forward Group has Mixed Field reaction

Answer 3

Patient transfused with Group O (investigate transfusion Hx), Blood group chimera (investigate patient Hx), or Bone marrow transplant (check Hx)

Question 4

ABO discrepancy: Reverse Group has weak or absent reaction

Answer 4

Agammaglobulinemia or hypogammaglobulinemia (check Hx), Newborn or elderly patient (check age & Hx), Immunocompromised patient, & Bone marrow transplant (check Hx)

Question 5

ABO discrepancy: Reverse group has unexpected positive reaction

Answer 5

Rouleaux formation (perform saline replacement), Cold antibody such as anti-M, P1, Lewis, I or HI (prewarm tech), Bone marrow transplant (check Hx), Anti-A1

Question 6

ABO discrepancy first steps when found

Answer 6

Re-check tubes and labels. Re-wash cells and repeat BOTH forward and reverse grouping. If discrepancy still exists then determine type of discrepancy and troubleshoot.