Asymptomatic bilateral ureteropelvic junction obstruction due to supernumerary renal arteries.

A supernumerary renal artery is a common arterial variation, which warrants considerations in a variety of urologic and retroperitoneal operations. Supernumerary renal arteries can be associated with other uro-vascular variations and anomalies such as duplicated renal veins and ureters, aberrant origin of the gonadal arteries, persistence of fetal renal lobulation, and kidney malrotation. The role of crossing supernumerary renal arteries in ureteropelvic junction obstruction (UPJO) is controversial. We report a healthy potential renal transplant donor with bilateral UPJO, which appeared to be secondary to supernumerary renal (inferior polar) arteries. We believe that the bilateral occurrence of asymptomatic UPJO associated with supernumerary renal arteries has not been previously reported.