Ex-vivo Management of Renal Calculi in Living Donor Kidneys: A Retrospective Study from Malaysia

Abstract

Renal transplantation has significantly improved outcomes for patients with End Stage Renal Disease (ESRD), with living kidney donors offering advantages such as better long-term survival and immediate graft function. However, the presence of renal stones in potential living donors has historically been a contraindication for transplantation due to the risks it poses to both the recipient and the donor. The objective of the study is to evaluate the feasibility and safety of ex-vivo management of renal calculi in living donor kidneys and its potential impact on the transplantation process. This retrospective study from Malaysia describes the ex-vivo management of renal calculi in living donor kidneys prior to transplantation, aiming to expedite the transplantation process for recipients in urgent need. A total of four living donors with incidental non-obstructing renal stones underwent ex-vivo surgery at University Malaya Medical Centre. Preoperative evaluations and risk stratification were performed to ensure the well-being of the remaining kidney. Intraoperatively, flexible uretero-renoscopy (URS) was used to visualize the collecting system of the graft kidney. In one case, the stone was successfully removed using a stone basket, while in the remaining cases, no stones were found, and the radio-opacity seen in preoperative imaging was identified as benign Randall's plaques. No immediate complications or compromise in early graft function were observed. Both donors and recipients remained well during the follow-up period, with no occurrences of urolithiasis. The ex-vivo procedure added minimal cold ischemia time to the transplantation process, allowing quick access to the collecting system while being cautious not to injure the ureter.In conclusion, ex-vivo management of renal stones in living donor kidneys represents a potential solution to expand the pool of suitable organs for transplantation. However, the optimal operative management of graft urolithiasis remains debatable, and individualized assessment and multidisciplinary team discussions are necessary to ensure safety and success.  Long-term follow-up and larger studies are required to evaluate the impact of this technique on graft function and outcomes.