Comparison of miniaturized percutaneous nephrolithotomy and flexible ureterorenoscopy for the management of 10-20 mm renal stones in obese patients

To evaluate and compare effectivity and safety of flexible ureteroscopy (F-URS) and mini-percutaneous nephrolithotomy (mPNL) for 10-20 mm renal stones in obese patients. Between 2012 and 2015, charts of patients who were treated with F-URS or mPNL for 10-20 mm kidney stone(s) were analyzed. Patients with BMI > 30 kg/m(2) were enrolled into the study. Total of 315 patients were treated with mPNL, and 56 patients were matched our inclusion criteria. In the same period, F-URS was performed in 669 patients, and 157 of them had 10-20 mm kidney stones, and their BMI values were > 30 kg/m(2). The patients were retrospectively matched at a 1:1 ratio to index F-URS-mPNL cases with respect to the patient age, gender, ASA score, BMI and size, number, and location of stone. Gender, age, BMI, stone size, stone number, location of stone(s), and ASA scores were similar between groups. The mean operation time was significantly longer in mPNL group (p: 0.021). However, the mean fluoroscopy time was similar (p: 0.270). Hemoglobin drop requiring blood transfusion and angioembolization was performed in two and one patients after mPNL, respectively. Overall complication rate was significantly higher in mPNL group than F-URS group (30.3 vs. 5.3 %, p: 0.001). Our results demonstrated that both F-URS and mPNL achieve acceptable stone-free rates in obese patients with 10-20 mm renal stones. However, complication rates were significantly lower in F-URS group.