Objectives: To determine the stone-free rates and intra- and postoperative complication rates and grades of ureterorenoscopic stone treatment in patients with a solitary kidney. Methods: This study is a subanalysis of the Clinical Research Office of the Endourological Society (CROES) ureterorenoscopy (URS) study, which is a prospective international multicenter observational study. Over a 1-year period, consecutive patients treated with ureterorenoscopy for urinary stones were included. Patients entered in this analysis were those with a solitary functioning kidney. Descriptive data on patient characteristics, stone-free rates, complication rates, and grades were evaluated for three separate groups: patients treated with ureteroscopy for ureteral stones, for renal stones, and a combination of renal and ureteral stones. Results: A total of 301 patients were treated for stones in a solitary kidney; 219 were treated for ureteral stones. In this group, the stone-free rate was 88.6%, with an intraoperative complication rate of 7.4% and postoperative complication rate of 4.1%. Totally, 57 patients were treated for renal stones. In this group, the stone-free rate was 56.4%, with an intraoperative complication rate of 7.0% and postoperative complication rate of 10.5%. There were 25 patients who were treated for renal stones in combination with ureter stones. In this group, the stone-free rate was 60.0%, with an intraoperative complication rate of 12.0% and postoperative complication rate of 10.5%. Within the three groups, 72% of the postoperative complications were classified as Clavien I and II. Conclusions: Ureteroscopy is an effective and safe treatment modality for the removal of ureteral and renal stones in patients with a solitary kidney. Stone location as well as total stone burden seems to be important factors influencing the ability to render patients stone free. Moreover, single session ureteroscopic stone removal was less effective for the treatment of larger renal stones or renal stones in combination with ureteral stones.
Keywords: renal stones; solitary kidney; stone treatment; ureteral stones; ureterorenoscopy; ureteroscopy; urolithiasis.