Retroperitoneal kidney transplantation with liver and native kidney mobilization: a safe technique for pediatric recipients

BACKGROUND: Pediatric kidney transplant (KT) using larger, deceased or living donor adult kidneys can be challenging in the pediatric population due to limited space in the retroperitoneum. Liver and native kidney (L/NK) mobilization techniques can be used in smaller and younger transplant recipients to aid in retroperitoneal placement of the renal allograft. Here, we compare the clinical outcomes of pediatric retroperitoneal KT with and without L/NK mobilization. METHODS: We retrospectively analyzed pediatric renal transplant recipients treated between January 2015 and May 2021. Donor and recipient demographics, intraoperative data, and recipient outcomes were included. Recipients were divided into two groups according to the surgical technique utilized: with L/NK mobilization (Group 1) and without L/NK mobilization (Group 2). Baseline variables were described using frequency distributions for categorical variables and means and standard errors for continuous variables. Tests of association with the likelihood of using L/NK mobilization were performed using standard χ(2) tests, t tests, and the log-rank test. RESULTS: Forty-six pediatric recipients were evaluated and categorized into Group 1 (n = 26) and Group 2 (n = 20). Recipients in Group 1 were younger (6.7 ± 0.8 years vs. 15. 3 ± 0.7, P < 0.001), shorter (109.5 ± 3.7 vs. 154.2 ± 3.8 cm, P < 0.001) and weighed less (21.4 ± 2.0 vs. 48.6 ± 3.4 kg, P < 0.001) than those in Group 2. Other baseline characteristics did not differ between Groups 1 and 2. One urologic complication was encountered in Group 2; no vascular or surgical complications were observed in either group. Additionally, no stents or drains were used in any of the patients. There were no cases of delayed graft function or graft primary nonfunction. The median follow-up of the study was 24.6 months post-transplant. Two patients developed death-censored graft failure (both in Group 2, P = 0.22), and there was one death with a functioning graft (in Group 2, P = 0.21). CONCLUSIONS: Retroperitoneal liver/kidney mobilization is a feasible and safe technique that facilitates implantation of adult kidney allografts into pediatric transplant recipients with no increased risk of developing post-operative complications, graft loss, or mortality.