Time to recurrent stone formation in patients with bladder or continent reservoir reconstruction: Fragmentation versus intact extraction

Purpose: Stone formation following bladder or continent reservoir reconstruction in children is a major source of long-term morbidity. We determine whether the method of stone removal (fragmentation or intact extraction) affected the time to stone recurrence in children after bladder reconstruction. Materials and Methods: Medical records from 1993 to 2003 were examined to identify patients with urinary reconstruction subsequently treated for bladder calculi at our institution. Retrospective review of the medical records was performed to determine the type of urinary reconstruction, time to stone recurrence, method of stone removal and length of followup. Kaplan-Meier analysis was performed with each stone episode considered as an individual event. Time to recurrence was measured in months from stone removal to identification of recurrent stones. Results: A total of 60 patients with bladder or continent reservoir reconstructions had undergone 103 stone removal procedures (range 1 to 8 procedures per patient). Patients were rendered stone-free after each procedure. Stones recurred following 42.4% of intact and 43.9% of fragmented extractions at a mean of 27.0 (SD 31.3) and 27.6 (SD 21.8) months, respectively. Kaplan-Meier survival analysis curves for intact and fragmented extractions were not statistically different. Conclusions: Time to stone recurrence in patients with bladder or continent reservoir reconstruction is not altered by the method of stone removal (fragmented versus intact extraction). Since recurrence remains a frequent problem in children after bladder augmentation and/or reconstruction, use of the least invasive modality should be the initial management recommendation.