[Rare cause of ureteral obstruction following renal transplantation]

The case of a 22-year-old man with an urinary tract obstruction which developed 4 weeks after renal transplantation is reported. Ureteral obstruction was caused by the ductus deferens, a very rare cause of ureteral obstruction. The importance of ultrasound examination as a very convenient, noninvasive method in the differential diagnosis of possible complications after renal transplantation is stressed.