Evaluation of nephrolithiasis and its risk factors in living kidney donor candidates

Living kidney donation is the preferred choice for renal transplantation due to superior short-tem and long-term recipient, patient, and graft survival. However, living donor safety is essential, and in-depth donor evaluation is required to minimize donor risk. Kidney stone disease is prevalent in the general population, and many kidney donor candidates have had recent or remote stone events. This review will explore the prevalence, causes, and required steps in donor evaluation for stones to maintain donor safety.

In the United States, the prevalence of kidney stones is about 10% but reported to be about 2-8% among kidney donor candidates. These include asymptomatic, symptomatic, and incidental stones found on CT imaging, which can now detect small calcifications of 1-2 mm or less. These images may also over represent punctate calcifications, which are Randall's plaques in the renal papillae that do not represent active stone disease.

Current data support donation when the donor does not have metabolic risk factors for stones and the retained kidney is stone free. Using the above guidelines, recurrent stone disease in donors or stone-related complications in recipients are uncommon, limited to a few percentage of patients.