P38 An Acute Hemolytic Transfusion Reaction Due to Anti‐Wra Antibodies.

Abstract

The Wra antigen is found on the red blood cells of approximately 1 : 1000 caucasians. Anti‐Wra antibodies have been reported to be present in 1 : 25 to 1 : 100 healthy blood donors and an even higher proportion of hospital patients. Wra incompatibilty might therefore be expected to occur in approximately one in 50,000 blood transfusions. Reports of hemolytic transfusion reactions (HTR) and hemolytic disease of the newborn (HDN) due to anti‐Wra are however rare. We report an acute HTR due to anti‐ Wra in a 58 year old male with MDS associated with rigors, shortness of breath and a significant rise in serum bilirubin from 16 μmol L−1 pre‐transfusion to 110 μmol L−1 immediately afterwards. This was accompanied by the appearance of bilirubin and urobilinogen in his urine and a fall in haemoglobin of nearly 2 g dL−1 following the transfusion. Anti‐ Wra was the only antibody implicated. Wra antigen expressing reference panel cells and the unit being transfused during the gave 2–3+ reactions by IAT against the recipient's plasma. The donation typed as positive with Wra antisera. The recipient typed as Wra antigen negative. The reaction resulted in the patient being admitted to hospital for 2 days. The increasing use of electronic issue may result in more frequent reports of reactions due to anti‐Wra as commonly used screening cells do not express this antigen.