Long-Term Outcomes of Living Kidney Donors Left with Multiple Renal Arteries: A Retrospective Cohort Study from a Single Center.

Background: The presence of multiple renal arteries (MRAs) is a common anatomical variant in living kidney donors. While MRAs are not considered a contraindication to donation, it remains uncertain whether leaving the donor with a kidney containing MRAs affects long-term outcomes. This study aimed to evaluate renal and clinical outcomes in donors based on the vascular anatomy of the remnant kidney. Methods: We conducted a retrospective cohort study of living kidney donors who underwent nephrectomy at our institution between 2011 and 2016. Donors were categorized according to the vascular anatomy of the remaining kidney: single renal artery (SRA) vs. multiple renal arteries (MRAs). Data on renal function, hypertension, diabetes mellitus, and cardiovascular events were collected at baseline and follow-up. The primary outcome was long-term renal function, which was measured by the estimated glomerular filtration rate (eGFR). Secondary outcomes included clinical comorbidities and postoperative complications. Results: Among 190 donors, 132 had a remaining kidney with a single artery and 58 had MRAs. Over a median follow-up of 89.5 months (SRA) and 74.5 months (MRA), there were no significant differences in eGFR (SRA: 66 mL/min vs. MRA: 65 mL/min, p = 0.60), serum creatinine (p = 0.86), or the incidence of hypertension (31.8% vs. 34.5%, p = 0.35). Rates of diabetes mellitus and cardiovascular events were similarly low and comparable between groups. Conclusions: Living kidney donors left with a remnant kidney containing multiple renal arteries have similar long-term renal function and clinical outcomes as those with a single renal artery. These findings support the feasibility of MRA retention in donor selection and contribute to evidence-based surgical planning and donor counseling.