Efficacy of ultra-mini percutaneous nephrolithotomy and retrograde intrarenal surgery in the treatment of 2-3 cm lower calyceal stones

We aimed to compare the efficacy and safety of ultra-mini percutaneous nephrolithotomy (UMP) and retrograde intrarenal surgery (RIRS) for the management of lower calyceal stones. A group of 136 patients with a single lower calyceal stone (2-3 cm in diameter) was divided into the UMP or RIRS groups. The average operation time in the RIRS group was significantly longer than that in the UMP group, and the intraoperative blood loss in the former was markedly less than that in the latter. Besides, in the RIRS group, the decreased value of postoperative Hb was obviously lower, the postoperative hospital stay was evidently shorter, and the total hospitalization expenses were markedly less than those in UMP group were. Moreover, the success rate of the first-stage lithotripsy in the UMP group was notably higher than that in RIRS group. The RIRS group had an obviously lower VAS score but a markedly higher BCS score than the UMP group six hours after surgery. At 24 h after operation, the levels of serum CRP, TNF-alpha and IL-6 in patients in both groups were remarkably increased, and they were evidently lower in the RIRS group than those in the UMP group were. Three days after surgery, the levels of serum CRP, TNF-alpha and IL-6 were notably lower in the UMP group than those in RIRS group were. RIRS and UMP are safe and effective in the treatment of 2-3 cm lower calyceal stones. The first-stage UMP is characterized by a high stone-free rate (SFR), short operation time and low postoperative infection risk, while RIRS is associated with less blood loss and low total expenses.