Ureteral stent encrustation, incrustation, and coloring: morbidity related to indwelling times.
OBJECTIVE
Ureteral stents are a fundamental part of many urologic procedures. Serious complications, including migration, fragmentation, and stone formation, still occur, especially when stents have been forgotten for a long time. No widespread consensus for the type or indwelling time to avoid ureteral stent complications has been reached, however. We investigated the correlation between the indwelling time and encrustation, incrustation, coloration, and resistance to removal.


METHODS
A total of 330 ureteral stents in 181 patients were examined.


RESULTS
Overall, 155 (47.0%) stents were encrusted, and the encrustation rate was 26.8% at less than 6 weeks, 56.9% at 6 to 12 weeks, and 75.9% at more than 12 weeks. A total of 46 (13.9%) stents resisted removal, and 3 of these could not be removed by cystoscopy. The median indwelling time was 72 (14-124) days for stents that resisted removal and 31 (30-60) days for irremovable stents. The frequency of encrustation with coloration was higher than that without coloration in the period of less than 6 weeks and the period between 6 to 12 weeks of indwelling time.


CONCLUSIONS
In our study, although ureteral stent encrustation was related to the indwelling time, heavily encrusted ureteral stents necessitating additional procedures for removal occurred within an indwelling time of 3 months. The exact interval for removal of an indwelling ureteral stent to avoid additional procedures for removal is therefore difficult to determine.
Department of Urology, Ohguchi Higashi Hospital, Yokohama, Japan. takashi_tk2001@yahoo.co.jp
Takashi
T
Kawahara
Hiroki
H
Ito
Hideyuki
H
Terao
Minoru
M
Yoshida
Junichi
J
Matsuzaki
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002408:Catheters, Indwelling / Q000009:adverse effects*; D003116:Color; D020878:Device Removal; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D015607:Stents / Q000009:adverse effects*; D013997:Time Factors; D014513:Ureter / Q000601:surgery*; D055815:Young Adult