Complications and associated factors of pediatric extracorporeal shock wave lithotripsy

We determined the safety, efficacy and complications of extracorporeal shock wave lithotripsy in managing pediatric urolithiasis and analyzed possible factors affecting the complication rate.

We retrospectively reviewed 128 patients younger than 16 years who had undergone extracorporeal shock wave lithotripsy with a Lithostar® lithotripter between January 2000 and December 2010. Stone clearance and complications were assessed at postoperative week 1, and months 1 and 3. Success was defined as no radiological evidence of stone, or fragments 4 mm or less. Treatment failure was analyzed to find any correlation with stone size. Complications were assessed with a specific focus on rehospitalizations during postoperative week 1.

The overall success rate was 93.5% (115 of 123 patients). Repeat treatment rate was 56.1% (69 patients). Extracorporeal shock wave lithotripsy failed in 8 children, who subsequently required ancillary procedures. Mean stone size in the treatment failure group was 17.03 mm, compared to 13.04 mm in the successfully treated group. A total of 22 patients (17.8%) had complications in postoperative week 1 but only 19 (15.4%, 12 boys and 7 girls) were rehospitalized at that time. Presence of a metabolic risk factor was the only predictive factor for complications. By comparison, we found a lower success rate and higher ancillary procedure rate in the group with complications.

Extracorporeal shock wave lithotripsy is effective for pediatric urolithiasis, with a small but substantial morbidity rate. Parents should be informed about possible rehospitalization following extracorporeal shock wave lithotripsy due to complications independent of stone size.