Introduction: Extracorporeal shock wave lithotripsy (ESWL) is an option for the treatment of urinary lithiasis. Objective: To describe the outcomes of ESWL for the treatment of urinary lithiasis in children. Methods: A descriptive and retrospective study of 51 patients with urinary lithiasis that underwent ESWL from 2014 to 2019. Results: Males and 15–18-year-old patients prevailed; 27.4% had prior surgery; 10-20 mm lithiasis of renal location and density between 400-799 HU were the most common; a double J stent was the most utilized urinary derivation prior to lithotripsy treatment; 7.8% required retreatment; 13.7% additional interventions; the stone-free rate was 74.5% at one month and 92.2% at three months. The size of the lithiasis was associated with the success of the treatment (p<0.023). The most frequent complication was steinstrasse; endourologic procedures were the most utilized, grade III b (Clavien-Dindo) prevailed and were associated to older patients (p=0.04), renal lithiasis localization (p=0.017), larger size (p=0.08), and density(p=0.036). Conclusions: ESWL is effective and safe for treating urinary lithiasis in children. Its success was significantly associated to smaller stone size and its complications to patients of older age, larger stone size, density and renal localization of the lithiasis.

Introduction: Surgery by lumboscopic approach is of choice for some work groups, despite being more arduous and requiring a higher learning curve. Objective: To assess the lumboscopic approach and identify predictive factors of complications and conversion to open surgery. Material and Methods: A transversal, retrospective study of 436 patients that underwent surgery by lumboscopy at the National Center for Minimally Invasive Surgery, 2008-2019. Absolute and relative frequencies; the Chi-Square Test and Student´s t Test and the Multiple Logistics Regression, were utilized, (p≤0.05). Results: Renal atrophy due to benign diseases (49.8%), renoureteral lithiasis (26.6%), surgery of moderate complexity (71.9%) prevailed, such as nephrectomy (50.2%). 16.1% had undergone prior surgery, and 12.4% a urinary derivation. 3% required conversion to open surgery and 18.8% presented complications. Renal staghorn and non-staghorn lithiasis, surgical technique, level of complexity of the surgery, operative time, transoperative bleeding and length of hospital stay were significantly associated (p<0.05) to complications, but after measuring logistics regression, only hospital stay resulted statistically significant (p=0.000). Regarding conversion: gender, past history of prior surgery, operative time and bleeding were significantly associated (p<0.05) in both the univariate and multivariate analysis. Conclusions: Nephrectomy due to benign causes and surgeries of moderate complexity prevailed in this series. The perioperative outcomes were satisfactory and the most frequent complications were postoperative, infectious and of grade II severity. Longer hospital stay was a predictive factor for complications whereas males, past history of prior surgery, longer operative time and bleeding were identified as predictive factors for conversion to open surgery.