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Management strategies and results for severely encrusted retained ureteral stents.

PURPOSE
To review the management approach to and results of severely encrusted retained ureteral stents and analyze predictive risk factors.


PATIENTS AND METHODS
Medical records from January 1996 to March 2006 were reviewed for Double-J stent complications and their final outcome. A total of 876 stents were inserted in 784 patients for treatment of renal calculi with extracorporeal shockwave lithotripsy, ureteral calculi, after percutaneous nephrolithotomy, pyeloplasty, or injury to the ureter and kidney. Of these stents, 95 (10.84%) were found to be encrusted, and 26 (2.96%) were not only encrusted but retained as well. These patients, 21 men and 5 women with a mean age of 34 years (range 18-69 years), underwent one or more of the following procedures: cystolitholapaxy, retrograde ureteroscopic manipulation, intracorporeal or extracorporeal lithotripsy, percutaneous nephrolithotomy, and open surgical removal to make them stent free.


RESULTS
The average duration of stent placement was 14 months (range 5 months-9 years). The encrustation was confined to the upper coil in 4 and the upper coil and body in 5. The lower coil and body in 8 and 9, respectively, were totally encrusted, of which 2 were fragmented as well. A total of 62 sessions of auxiliary procedures were required to render patients stent free. Four patients required percutaneous nephrolithotomy and one open removal.


CONCLUSION
Encrustation and retention of a ureteral stent is a serious complication. Successful management of encrusted retained stents requires multimodality procedures along with proper record keeping of stent insertion and removal and patient counseling.