MO965THE EFFECT OF DEGREE OF HUMAN LEUCOCYTE ANTIGEN MISMATCH AMONG LIVE-DONOR KIDNEY TRANSPLANT RECIPIENTS

Abstract

Abstract Background and Aims There is a strong evidence of importance of HLA matching in kidney transplantation and associations between HLA-DR mismatches and rejection, transplant glomerulopathy, graft failure, and death with functioning graft following kidney transplantation. Our aim is to evaluate the effect of degree of HLA mismatch on transplant outcome among live donor kidney transplant recepients. Method The current study is a retrospective cohort study which was performed in Urology and Nephrology Center, Mansoura University, Egypt. The study included 2200 kidney transplant recipients who underwent renal transplantation between March 1976 and August 2019. The patients were divided into 3 main groups according to the degree of HLA mismatch: Group I: 0, 1, 2 HLA mismatch (568 patients). Group II: 3 , 4 HLA mismatch (1462 patients). Group III: 5 HLA mismatch (170 patients Results Demographic and medical characteristics were comparable among the 3 groups. Transplantation from unrelated donors was more frequent among group III (p value: 0.001). Ischemia time was comparable and over 90% of the patients had immediate diuresis.The degree of HLA mismatch affected the choice of induction therapy as lymphocyte depleting agent (ATG) was used more frequently in group III while basliximab was used more frequently in group I (p value: 0.001). Patients in group I were maintained on dual immunosuppressive protocols more frequently than the other 2 groups where triple immunosuppressive protocols were commonly used (p value: 0.02).Tacrolimus-based protocol was used more among group I while cyclosporine-based regimen was frequently used among group III (p value: 0.002, 0.001 respectively). acute rejection episodes were more frequent with group II and III. (p value: 0.001). Chronic rejection was revealed in graft biopsies of group II and III more than group I (p value: 0.046). Incidence of post-transplant Hypertension and Diabetes mellitus was higher in group III (p value: 0.004, 0.016 respectively). Median serum creatinine after 1 year follow up didn't differ significantly between the studied groups. However, serum creatinine was higher in group III after 2, 3, 4 and 5 years post transplantation (p value: 0.006) with subsequent lower creatinine clearance (p value: 0.036). The majority of patients were alive with functioning graft at last follow-up especially in group I with statistically significant difference among the 3 groups (p value: 0.001). More patients were alive with failed graft at last follow up in group III than in the other 2 groups with statistically significant difference (p value: 0.003). There was comparable percent of patients among the 3 groups were died either with functioning or with failed graft. On the other hand the 5, 10 and 15 years graft and patient survival showed statistical significant difference among the 3 groups with better survival for group I (p value: 0.04, 0.001) Conclusion The degree of mismatch affected the choice of immunosuppressive regimen. Higher HLA mismatch was associated with higher incidence of diabetes and hypertension and lower patient and graft survival.