High quality transfusion and HLA services - prerequisites for successful ABO incompatible kidney transplantation

Abstract : Background - Modern desensitization protocols have enabled successful ABO incompatible kidney transplant (ABOiKT). We report a case of ABOiKT that elucidates the crucial role of support services including provision of high quality, reliable tools to screen for red cell as well as anti HLA antibodies to ensure an event-free pre and post-transplant period. Case report - A 21 years old gentleman of blood group O-positive was to receive a renal allograft from his HLA haplo-matched mother with blood group A-positive. His initial HLA-crossmatch by Complement Dependent Cytotoxicity (CDC) was negative and anti-A titre at presentation was 1-512. The transfusion and immunology lab services support was central to several challenging decisions that were undertaken during this transplant. Despite the high initial anti-A antibody titre, the patient underwent successful desensitization with Rituximab, plasmapheresis and Anti-thymocyte globulin, guided by the antibody measurements. Among the platforms for red cell antibody monitoring, the CAT was chosen in view of its several advantages. The monitoring frequency was determined after considering the frequency of plasmapheresis and the possibility of rebound. Adequate inventory of group A and AB fresh frozen plasma contributed to decreasing titres and event -free apheresis procedures. More sensitive assays were used to detect the presence of detrimental anti-HLA Antibodies. The low grade pre-transplant CDC crossmatch positivity was clarified as attributable to Rituximab use, by the clearly negative ELISA screen and Luminex crossmatch (DSA using donor lysate). With effective desensitization the anti-A titre was reduced to 1-2 against which transplantation was performed successfully. Currently, three years post-transplant the graft is functional the patient is doing well. Conclusion - This case demonstrates the centrality of the Transfusion and Immunology lab services in crafting the success of an ABOiKT as well as the importance of the interface between the laboratory and the clinician in this scenario.