Background/Case Studies: A group A, D positive 61-year-old Caucasian female with a history of a cold autoantibody and anti-Fya developed multiple additional alloantibodies – anti-c and anti-Jkb following transfusion of one unit of O positive red blood cells (RBCs). Two weeks later, upon readmission to a trauma hospital and further transfusion of antigen-negative group O RBCs, she experienced signs of a transfusion reaction, including increased bilirubin and liver enzymes. The referring facility ordered a post-transfusion reaction investigation. When tested by the facility, the sample demonstrated pan-reactivity which was unable to be resolved or attributed to any antibody specificity; therefore, a sample was referred to the Immunohematology Reference Laboratory (IRL) for further evaluation. Upon arrival to the IRL, the sample was grossly hemolyzed and icteric. Initial testing revealed no mixed field in the forward ABO typing, indicating a possible transfusion reaction caused by an additional antibody that was not yet previously identified.
Study
Design/Methods: The IRL’s serologic testing was performed using tube techniques and red cell treatments including Direct Antiglobulin Test (DAT), Low-Ionic Strength Solution (LISS), Dithiothreitol (DTT), antisera, and in-house antigen negative donor units.
Results/Findings: A selected cell panel made up of commercially prepared reagent cells, which included cells positive and negative for previously identified antibodies was created. Extensive serologic testing revealed a strong antibody reactive at all phases, with all reagent red cells using LISS tube technique. The DAT-IgG and autologous control were negative, the DAT-C3b was 1+ positive. The antibody reactivity strength after 0.01M DTT treatment of the patient plasma remained unchanged at LISS-IAT, but was negative at IS and 37C readings with all cells tested. The pattern of reactivity and persistence after 0.01M DTT treatment led to the suspicion of an antibody to a high prevalence antigen, with an IgM and IgG component. A panel of Group O cord cells and group A donor RBCs was created and yielded negative results at all phases with cells antigen negative for c, Jkb, and Fya, using LISS tube technique. No additional alloantibodies were identified. These serologic results led to the conclusion that the newly identified antibody was clinically significant, anti-IH. Conclusions: This case emphasizes that antigens with ABO-specific expression need to be kept in mind as a risk of producing an adverse reaction when transfusing out-of-type blood products. Future transfusions for this patient required group A RBCs in conjunction with the use of a blood warmer to prevent future transfusion reactions caused by clinically significant anti-IH.
