Outcomes of retrograde intrarenal surgery compared with ultra-mini percutaneous nephrolithotomy in the management of renal calculi

INTRODUCTION: To evaluate the outcomes of retrograde intrarenal surgery (RIRS) and ultra-mini percutaneous nephrolithotomy (umPCNL) in the management of renal calculi. MATERIAL AND METHODS: Between March 2015 and January 2018, a total of 44 patients were treated with umPCNL. The outcomes of these patients were compared with 75 patients who underwent RIRS for renal calculi during the same time period. RESULTS: Median stone size was 9 mm in the umPCNL group and 7 mm in the RIRS group. Stone-free rates after a single procedure were achieved in 85% of patients for the RIRS group and 98% for the umPCNL group. 16% of RIRS patients were left with a ureteric stent, whilst 7% of patients (n = 5) needed a second RIRS. One patient in the umPCNL group was left with a percutaneous nephrostomy; all other patients were left totally tubeless. The mean operative time was 66 minutes in the RIRS group and 55 minutes in the umPCNL group (p = 0.04). The minor complication rates for the RIRS and umPCNL groups were 17% and 15%, respectively. One patient in the RIRS group required postoperative nephrostomy insertion; there were no major complications in the umPCNL group. The median length of stay was 0 days in the RIRS group and 1 day in the umPCNL group. CONCLUSIONS: The overall study showed that umPCNL has low complication rates and good stone-free rates, with a lower requirement for ancilliary procedures. UmPCNL is an acceptable alternative in selected patients with small- to moderate-sized renal calculi.