Treatment of renal stones with flexible ureteroscopy in preschool age children.

The aim of the study is to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) to treat renal stones in preschool age (<7 years) children. From September 2005 to May 2013, a total of 65 children (31 boys and 34 girls) with 72 renal stones were treated using RIRS. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. In the presence of residual calculi >4 mm, a second-stage RIRS was performed. The pre-operative, operative and post-operative data of the patients were retrospectively analyzed. A total of 65 patients with a mean age of 4.31 ± 1.99 years (6 months-7 years) were included in the present study. The mean stone size was 14.66 ± 6.12 mm (7-30 mm). The mean operative time was 46.47 ± 18.27 min. In 5 (7.69%) patients, the initial procedure failed to reach the renal collecting system and ended with the insertion of a pigtail stent. The stone-free rates were 83.07 and 92.3% after the first and second procedures, respectively. Complications were observed in 18 (27.7%) patients and classified according to the Clavien system. Post-operative hematuria (Clavien I) occurred in 6 (9.2%) patients, post-operative urinary tract infection with fever (Clavien II) was observed in 10 (15.4%) patients, and ureteral wall injury (Clavien III) was noted in 2 (3%) patients. RIRS is an effective and safe procedure that can be used to manage renal stones in preschool age children.