A Self-Expanding Thermolabile Nitinol Stent as a Minimally Invasive Treatment Alternative for Ureteral Strictures in Renal Transplant Patients

Abstract

Ureteral obstruction in renal transplant allografts secondary to strictures can pose a challenging problem. Its incidence is reported between 0.5% and 4.7%. Usually, open surgical repair is performed. We present a series of patients in whom a metal Memokath™ 051 stent has been used as a minimally invasive treatment alternative. We analyzed our data on the use of thermo-expandable metallic Memokath 051 stents for ureteral strictures in renal transplant patients. Between 2003 and 2010, eight male kidney recipients with a mean age of 49 years and obstructed ureters after kidney transplantation were treated with ureteral Memokath insertion. In six patients, the obstruction was at the level of the anastomosis, and in two, at the pelviureteral junction. After a mean follow-up of 4 years, half of the stents are in situ providing a good graft function. The average indwelling time is 4 years. Spontaneous resolution of the stricture without the need for further stent insertion was seen in three patients after a mean indwelling time of 7.3 months. There was one treatment failure in a patient with an obstructed, dilated, and convoluted ureter that was unable to withhold the stent in situ. No perioperative complications were recorded in this series. The overall success rate was 87%. Ureteral stent placement with the Memokath 051 is a safe minimally invasive treatment alternative for ureteral strictures in renal transplant recipients.