Management of encrusted ureteral stents

Objectives: To present our experience in managing encrusted ureteral stents and to review the literature on the subject. Methods: A total of 22 patients with encrusted ureteral stent were treated in our department. Encrustation of the stent and associated stone burden were evaluated using plain radiography, sometimes supplemented by intravenous urography or ultrasonography. The treatment method was determined by the site of encrustation, the size of the stone burden and the availability of endourologic equipment. Results: Stents were inserted for stone disease in 17 patients, for congenital abnormality in 3 and for ureteric obstruction by malignancy in 2. Stents were left in place for a mean of 10.8 months (range 5–34 months). The site of encrustation was in the bladder in 15 (68.2%), ureter in 13 (59%) and kidney in 8 patients (36.4%); more than one site was involved in 11 (50%) cases. For upper coil encrustations, retrograde ureterorenoscopy was performed in 9 cases, percutaneous nephrolithotomy in 4 and open pyelolithotomy in 2. For lower coil encrustation, fragmentation by grasper and/or transurethral cystolithotripsy was attempted in 11 cases, and suprapubic cystolithotomy was required for failure in 7 cases. Sixteen patients (72.7%) were rendered stone-free and 5 (22.7%) had clinically insignificant residual stones (3mm or less). Conclusions: Encrustation is one of the most difficult complications of ureteral stents and its management is a complex clinical scenario for the treating surgeon. The combination of several surgical techniques is often necessary but the best treatment remains the prevention of this problem by providing patient education.