P KOTAGIRI1, R MASTERON1, P HUGHES1, M HAEUSLER1, S HOLT1, C HOGAN1
1Royal Melbourne Hospital, Melbourne, Victoria
Background: Blood group antigens are red blood cell surface markers made of either protein or carbohydrate and are defined serologically by an antibody. The role of most are unknown. Antibodies against these antigens cause varying degrees of red blood cell hemolysis. Antibodies against the major ABO blood groups cross-reacts with similar antigens on the kidney causing hyper-acute rejection without therapy. Non-ABO red blood cell antigens can cause transient red blood cell hemolysis due to antigen positive passenger red blood cells. Renal transplant rejection may occur, where the red blood cell antigen is present on the endothelial cells of vasculature or renal epithelium and is structurally immunogenic. Of the common non-ABO red blood cell group antigens, there is evidence of renal expression with the MNS, Lutheran, Lewis, Duffy and Kidd groups.
Case report: We present a case series of renal transplants with mismatched non-ABO red blood cell group antigens and examine the evidence that this can cause rejection. We illustrate the merits of treatments including; increased immunosuppression, plasma exchange and warming of the kidney, to help prevent rejection.
Conclusion: Future studies are required to help delineate the significance of the non-ABO red blood cell antigens and the most effective therapy. More extensive red blood cell antigen and antibody screening pre-transplantation may help identify patients at risk. The use of transfusion matching and antibody depleted FFP may help prevent antibody formation. In the presence of known non-ABO red blood cell antigen mismatch and rejection with no donor specific antibody, there may be a role for testing for non-ABO red blood cell group antibodies.