V04-06 ENCRUSTATED METALLIC URETERAL STENT TREATED BY MINI NEPHROLITHOTOMY

Abstract

INTRODUCTION AND OBJECTIVE: The use of polymeric double J stents for the management of ureteral strictures is effective for a short period of time, although they have limited use due to the risk of obstruction and to the need for periodic stent changes. Metal stents have been developed with the aim of maintaining greater ureteric patency, alleviating symptoms, and, especially, allowing less frequent exchanges. Although metallic stent changes are approved for 12 months, there are no concrete data defining a safe dwell-time to prevent clinically significant encrustations. Likewise, there are no reports of surgeries performed to treat metal stent encrustations. Our objective with this video is to describe a case of a large metallic ureteral stent encrustation successfully treated by Mini Percutaneous Nephrolithotomy (MiniPerc) in an obese patient. METHODS: A 48-year-old female was admitted at our hospital for treatment. The patient had previously undergone a metallic DJ stent implantation for the treatment of a chronic ureteral stricture but hasn’t had a stent exchange in the last 18 months due to loss of follow-up. Radiological exams revealed a large encrustation at the right renal pelvis (2,5x1,6cm). After the attempt of removing the stent by cystoscopy failed, a mini percutaneous nephrolithotomy was performed to treat the kidney stone and to implant another stent. RESULTS: After the procedure, the patient became stone-free and had a silicone DJ stent implanted. Metabolic evaluation of the urine did not reveal hypercalciuria or any other contributing factor for this severe complication. CONCLUSIONS: Large encrustations on a metallic ureteral stent are rare complications and may require surgical treatment. Mini percutaneous nephrolithotomy seems to provide a safe and feasible treatment option for these cases, even in obese patients. Source of Funding: Authors