Ultra-mini percutaneous nephrolithotomy (UM-PCNL) with a semi-rigid ureteroscope in pre-school children: An Innovative Experience in Southern Iran

Background: Since its inception, percutaneous nephrolithotomy (PCNL) has undergone extensive modification to reduce post-operative complication rates and provide easier renal access to the surgeon. One of the recent advances in minimally invasive procedures is the advent of ultra-mini PCNL (UM-PCNL) which provides miniaturized access to the upper urinary tract. However, the specific instruments applied in UM-PCNL may not be found in centers with limited resources. In this single-center study, we evaluated the feasibility and short-term complication rates of performing UM-PCNL using a semirigid ureteroscope with a 4Fr tip instead of an ultra-mini nephroscope in preschool children aged less than seven years old. Results: : A total of 68 patient records (42 M:26 F) with a mean age of 3.2±2.4 years were retrospectively evaluated in this study. Short-term complications were defined as those occurring within three weeks after surgery. The early stone-free rate (SFR) was 91% and the short-term total SFR stood at 97%. No statistically significant difference in preoperative and postoperative Hb, Bun, Cr, Na, and K was found. Fever (11 patients) and ileus (5 patients) constituted the majority of complications and only one patient required a blood transfusion. None of the cases undergoing UM-PCNL with this method required a re-do PCNL. Conclusion: Our experience shows that with sufficient experience in maneuvering the semi-rigid ureteroscope, urologists practicing in centers with limited resources could perform UM-PCNL with relatively favorable outcomes.