Extracorporeal Shockwave Lithotripsy Versus Flexible Ureteroscopy for the Management of Upper Tract Urinary Stones in Children.

Objective: To compare the efficacy and morbidity of extracorporeal shockwave lithotripsy (SWL) and flexible ureteroscopy (F-URS) for the management of upper tract urinary stones in children. Methods: All SWL and F-URS performed in children in a single institution between 2000 and 2014 were reviewed retrospectively. Only procedures performed to treat upper tract urinary stones (upper ureter or kidney) were included in this study. Preoperative and perioperative outcomes were compared between the SWL and F-URS groups. Univariate and multivariate logistic regression analyses were used to evaluate predictors of stone-free (SF) status. Results: Over the study period, 100 SWL and 46 F-URS were conducted in 69 children. The SWL and F-URS groups were comparable in terms of stone size (14.6 vs 13.2 mm, p = 0.32), but there were more multiple stones (31% vs 57%; p = 0.003) and lower pole calculi (14% vs 37%; p = 0.003) in the F-URS group. The SF rate after one procedure was almost two times higher in the F-URS group compared with the SWL group (37% vs 21%; p = 0.04) without increasing the complication rate (21.7% vs 16%; p = 0.31). Similar results were observed in the subgroup of single renal stones <20mm (SF rates: 78.6% vs 50%; p = 0.06). In multivariate analysis, the use of F-URS vs SWL was a predictor of an SF status (odds ratio = 3.7; p = 0.02). Conclusion: F-URS provides a higher single-session SF rate, despite more complex urinary stones (multiple, lower pole, etc.) and without increasing morbidity.