Results of shockwave lithotripsy for pediatric urolithiasis.

Abstract

Shockwave lithotripsy (SWL) is widely practiced in the management of pediatric urolithiasis. However, the efficacy, need for ancillary procedures, and treatment-related complications are not as clearly defined as in the adult population. We reviewed the outcomes of SWL in the pediatric population at our lithotripsy unit. A retrospective review of all patients </=16 years of age treated with SWL between January 1991 and June 2002 was undertaken. One hundred patients with 115 stones underwent 131 SWL procedures (115 first treatments, 16 retreatments). The mean age was 10.7 years (range 10 months-16 years). Stone locations were as follows: caliceal 42.6%, renal pelvic 27%, and ureteral (30.4%). The mean stone size was 7.8 mm (range 2-23 mm). Risk factors for stone formation, the need for secondary therapies, and treatment-related complications were noted. The stone-free rate for a single-session SWL procedure, defined as complete absence of stone fragments on plain film, intravenous urography, or renal ultrasonography, was calculated based on 3-month follow-up. The efficiency quotient (EQ) was also calculated. Risk factors were identified in 31 children (27.0%), including metabolic and anatomic abnormalities. Patients with a risk factor were less likely to be stone free after one SWL session than those without risk factors (31.7% v 64.7%; P < 0.001). General (74.8%), neurolept (24.4%), and epidural (0.8%) anesthesia were utilized. Ureteral stents were placed in 25% of treatments. There were no intraoperative complications. Minor complications were seen in 4.6% of patients. Ancillary procedures were required in 10 patients. Following initial SWL treatment, 60.2% of patients were stone free. The retreatment rate was 13.9%. Following a second treatment, the stone-free rate increased to 68%. The EQ was 54.3. Employing a strict definition of treatment success, single-session SWL in our series offers moderate efficacy in the pediatric population. Patients who have a large stone or risk factor such as an anatomic abnormality are less likely to become stone free and might better undergo an endourologic procedure.