Pediatric retrograde intra-renal surgery for renal stones <2 cm in solitary kidney.

INTRODUCTION: Management of renal stones in children with a solitary kidney is a challenge. In the current study, the efficacy and safety of retrograde intrarenal surgery (RIRS) in these children were determined.

PATIENTS AND METHODS: Records of children with renal stones who were treated at our institute between August 2011 and August 2014 were retrospectively assessed. Inclusion criteria were: Children with single renal stone <2 cm size, in a solitary kidney. A 7.5 Fr flexible ureteroscope (FURS) was introduced into the ureter over a hydrophilic guidewire under visual and fluoroscopic guidance - applying a back-loading technique. The stone was completely dusted using 200 μm laser fiber (0.2-0.8 joules power and 10-30 Hz frequency). At the end of the maneuver, a 5 Fr JJ stent was inserted into the ureter. The children were discharged home 24 h postoperative - provided that no complications were detected.

RESULTS: Fourteen children (3 girls and 11 boys) with median age 9.5 years (range 6-12) were included. The mean stone burden was 12.2 ± 1.5 mm (range 9-20). Stones were successfully accessed in all of the cases by the FURS except for 2 cases in whom a JJ stent was inserted into the ureter and left in place for 2 weeks to achieve passive dilatation. All of the stones were dusted completely. The immediate postoperative stone-free rate (SFR) was 79%, and the final SFR was 100% after 3 weeks. No intraoperative complications were observed.

CONCLUSIONS: RIRS for renal stone <2 cm in children with a solitary kidney is a single-session procedure with a high SFR, low complication rate, and is a minimally invasive, natural orifice technique.