Retrograde Intrarenal Surgery (RIRS) for upper urinary tract stones in children below 12 years of age: A single centre experience

Objective: Retrograde Intra Renal Surgery (RIRS) is a minimally invasive surgical modality for the treatment of renal stones. We evaluated the efficacy of RIRS in children below aged 12 years of age in the form of stone-free rate (SFR), complications and the feasibility of the procedure. Materials and methods: This retrospective study included all children ≤ 12 years of age, with upper urinary tract stones single or multiple ≤ 15 mm in size who underwent RIRS between February 2019 to November 2021. RIRS was performed with 7.5 Fr flexible ureterorenoscope over the guidewire, the stones were dusted with Laser and the ureteral stent was left after RIRS. All patients had the post-procedure stent removed within 3 weeks after checking for residual stones with X-ray and ultrasonography of Kidney-Ureter-Bladder (USG-KUB). Follow-up USG KUB was done at 4 months. Results: 15 patients included in our study met the inclusion criteria. The mean age was 8.7 ± 2.8 years, the mean stone size was 11.26 ± 2.14 mm and 26.6 % had multiple stones. Retrograde access failure was noted in 36.3 % in non stented patients. The mean operative time was 72.6 ± 20 minutes, fluoroscopy time was 4.4 ± 0.9 minutes and the mean LASER time was 26 ± 3.9 minutes. The mean hospital stay was 2.8 ± 0.9 days. Ureteral access sheath (UAS) was used in one patient. Conversion to mini PCNL was done in one pre stented patient due to access failure and one patient had a second look RIRS for residual stone. No major complications were noted except onr patient who had sepsis. The stone-free rates were 93.3% after primary RIRS and 100% after second look RIRS. Conclusions: RIRS is a feasible, safe procedure for pediatric upper urinary stones with excellent stone-free rates and a low rate of complications.