Development of de novo HLA donor specific antibodies (HLA-DSA), HLA antibodies (HLA-Ab) and allograft rejection post blood transfusion in kidney transplant recipients

Background: Blood transfusion during the post-operative period of kidney transplantation is common as part of a life-saving procedure, especially in the event of acute blood loss. However, there have been conflicting opinions since the pre-cyclosporine era. The risk of sensitization post-transfusion remains the main limiting factor following transfusion in kidney transplant recipients. Thus, the objective of this study is to assess the development of de novo HLA-DSA, HLA-Ab and allograft rejection post blood transfusion. Methodology: This is a retrospective cohort study recruiting all kidney transplant recipients in South Australia from January 2010 till December 2018. Following that, the incidence of blood transfusion within one week post-operatively were traced (transfusion group). The outcomes were compared with all other transplant recipients (non-transfusion group). Recipient's demographic, donor characteristics and immunological risk profiles were obtained from the transplant unit database, while the biopsy report, history of blood transfusion, latest serum creatinine and follow-up status was gathered from the electronic medical system (OASIS). The HLA-DSA and HLA-Ab results were collected from the NOMS database. Finally, the survival data were merged with the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry for South Australia recipients graft survival. Results: A total of 699 patients were eligible for analysis. The mean age was 50.64 +/- 13.23 years old. There were more elderly (> 65 years old) and females who needed transfusion. The majority had glomerulonephritis as the primary disease. There was no statistical difference in donor characteristics, cold ischemic time and immunological risk between the transfusion and non-transfusion group. There was no difference in the development of de novo HLA-DSA, HLA-Ab and rejection episodes between the group and the results were consistent in a model adjusted for all potential confounders. Median graft survival in days between the transfusion vs non-transfusion group was 1845 IQR (961,2430) and 1250 IQR (672,2013). Conclusion: Blood transfusion under strong immunosuppressive cover within a one-week post-operative period is safe with no significant association with the development of de novo HLA-DSA, HLA-Ab or clinical rejection.