Stone Disease in Living-Related Renal Donors: Long-Term Outcomes for Transplant Donors and Recipients

Background and Purpose: Historically, patients wishing to donate their kidney to living related recipients were deemed ineligible if preoperative imaging demonstrated nephrolithiasis. We assess the outcomes of donors with nephrolithiasis and the outcomes of their recipients. Methods: Donors undergoing nephrectomy between 2001 and 2011 who had nephrolithiasis on preoperative computed tomography (CT) imaging or a history of stone passage were identified. A retrospective chart review documented donor and recipient demographics, donor 24-hour urine collections, stone size and location, stone events after transplant, and graft function. A seven-question telephone survey regarding development and/or presence of symptomatic nephrolithiasis was conducted. Results: Fifty-four donor-recipient pairs met the inclusion criteria. Twenty-eight (51.9%) patients had valid preoperative 24-hour urine collection, seven (25%) of whom had hypercalciuria. Seven (13%) patients had previous symptomatic nephrolithiasis, but no stones on imaging. Forty-one patients donated a kidney with at least one stone, with a mean stone size of 2.4mm (range 1-6mm). Median follow-up for donors and recipients was 22.5 months (interquartile range [IQR] 1-79.3) and 47.4 months (IQR 25.1-76.1), with 50% and 77.7% having a follow-up of more than 2 years, respectively. One donor with nephrolithiasis on preoperative imaging who donated the contralateral kidney passed a stone spontaneously after visiting the emergency department. Otherwise, no other donors or recipients experienced any stone episodes during the follow-up period. Conclusion: The risk of clinical stone recurrence in donors and recipients is low: As such, presence of small caliceal stones should not constitute an exclusion for living-related kidney donation.