Single versus multiple renal arteries in living donor kidney transplantation: A systematic review and patient-level meta-analysis

Grafts with multiple renal arteries (MRAs) were historically considered a relative contraindication to transplantation due to the higher risk of vascular and urologic complications. This study aimed to evaluate graft and patient survival between single renal artery (SRA) and MRA living-donor kidney transplants. An electronic literature search was conducted on PubMed, EMBASE, and Scopus for prospective or retrospective studies comparing SRA versus MRA in living donor renal transplantation, with the provision of Kaplan-Meier curves for recipient overall survival (OS) or graft survival (GS). A graphical reconstructive algorithm was used to obtain OS and GS of individual patients, which was then pooled under random-effects individual patient data (IPD) meta-analysis using Cox-models to determine hazard ratios (HRs) and 95% confidence intervals (CIs). Meta-regression of baseline covariates versus HRs of OS and GS was performed for variables reported in 10 or more studies. Fourteen studies were retrieved, of which 13 (8400 patients) reported OS and 9 (6912 patients) reported GS. There were no significant differences in OS (shared-frailty HR = .94, 95%CI = .85-1.03, p = .172) or GS (shared-frailty HR = .95, 95%CI = .83-1.08, p = .419) between SRA and MRA. This comparison remained non-significant even when restricted to open- or laparoscopic-only studies. Meta-regression yielded no significant associations of GS with donor age, recipient age, and percentage of double renal arteries within the MRA arm. The similar rates of GS and OS between MRA and SRA grafts suggest that there is no need for discrimination between the two when evaluating donors for nephrectomy.