Long-term renal outcomes in living kidney donors with asymptomatic nephrolithiasis: a 10-year single-center study

Abstract

Nephrolithiasis remains an important consideration in living kidney donor evaluation, but long-term outcomes in carefully selected donors with asymptomatic stones remain incompletely defined. We evaluated renal functional trajectories and postdonation stone recurrence among donors with incidental nephrolithiasis identified during predonation assessment. In this single-center retrospective cohort study, all living kidney donors who underwent nephrectomy between March 2007 and March 2017 under a standardized age-stratified protocol were analyzed. Donors with asymptomatic nephrolithiasis on predonation computed tomography were compared with stone-free donors. Primary endpoints were postdonation stone recurrence and estimated glomerular filtration rate (eGFR; 2021 Chronic Kidney Disease Epidemiology Collaboration equation) at last follow-up. Multivariable and longitudinal mixed-effects models were used to evaluate renal outcomes. Among 1444 approved donors, 52 (3.6%) had asymptomatic nephrolithiasis; 44 were included in the final analytical cohort. No donor developed radiologic recurrence or symptomatic stone events during extended follow-up. Nephrolithiasis was not independently associated with last follow-up eGFR, ≥30% decline in eGFR, or longitudinal renal functional trajectories. Carefully selected donors with small, asymptomatic stones demonstrated favorable long-term outcomes, supporting a risk-stratified approach to donor selection.