Impact of renal allograft nephrectomy on graft and patient survival following retransplantation: a systematic review and meta-analysis

Background. It is not clear whether renal allograft removal affects the outcome of renal retransplantation. This study aimed to determine the effect of allograft nephrectomy (AN) and noAN (No AN) on renal retransplantation. Methods. A systematic review and meta-analysis were conducted using MEDLINE, Embase and the Cochrane Library. Observational studies or randomized controlled trials including renal retransplantation recipients with AN or No-AN were included. The primary outcomes were graft survival, patient survival, acute rejection (AR) and delayed graft dysfunction; the secondary outcomes were positive panel reactive antibody rate and serum creatinine level at 1 year after retransplantation, cold ischemia time and time of hemodialysis before recent transplantation. Pooled estimates of odds ratios (ORs) and the weighted mean difference for outcomes were calculated. Results. A total of 13 studies divided into 20 trials including 1923 patients were analyzed. The No-AN group had a significantly higher 3-year graft survival rate {OR 0.48 [95% confidence interval (CI) 0.34-0.69], 10 studies, n = 1030} and 5-year graft survival rate [OR 0.65 (95% CI 0.44-0.97), 16 studies, n = 1878] than the AN group. The rates of 5-year patient survival [OR 1.82 (95% CI 1.14-2.90), 5 studies, n = 749], positive panel reactive antibody [OR 3.08 (95% CI 2.08-4.56), 12 studies, n = 1225], AR [OR 1.59 (95% CI 1.21-2.09), 15 studies, n = 1388] and delayed graft dysfunction [OR 1.66 (95% CI 1.20-2.03), 8 studies, n = 879] were all significantly higher in the AN group. Compared with the No-AN group, cold ischemia time was longer in the AN group [weighted mean difference 1.84 (95% CI 0.90-2.79), 7 studies, n = 919]. The rate of 1-year graft survival and 10-year graft survival, serum creatinine levels at 1 year after retransplantation and the time of hemodialysis before recent transplantation were similar between the AN and No-AN groups. Conclusions. We recommend allowing the failed graft to remain unless symptoms dictate the need for surgery. We also suggest donor-specific antibody dynamic monitoring and better human leukocyte antigen matching for improved long-term outcome of retransplantation.