OBJECTIVE - To assess stone-related events (SREs) requiring retreatment in a series of 100 consecutive patients treated by retrograde intrarenal surgery for renal stones and to evaluate potential risk factors thereof.
PATIENTS AND METHODS - The primary outcome was incidence of SRE (medical or surgical treatment). Secondary outcomes included side of SRE, time to SRE, and late complications. Retrospective analysis of potential risk factors included high-risk stone formers (HRSF), obesity, high stone burden, and lower pole stones. In addition, we evaluated endoscopically determined small residual fragments of
RESULTS - Eighty-five of the 99 patients were followed up for a mean of 59 months (31-69), among whom 26 (30.1%) had SRE. Thirty-four of the 85 (40%) patients were HRSFs, 22 of whom experienced SRE (both sides) during follow-up (64.7%, p<0.001). Eight of the 17 patients (47.1%) with SRF experienced ipsilateral side SRE, compared with 13 (19.1%) of the 68 without ipsilateral SRE (p=0.022, hazard ratio [HR] 2.823 [CI 1.16-6.85]). Risk for ipsilateral SRE was unaffected by the presence of SRF among HRSFs (p=0.561). Of low-risk patients with SRF, 33.3% experienced ipsilateral SRE, while those without SRF experienced no ipsilateral SRE (p<0.001).
CONCLUSIONS - Endoscopically determined stone clearance predicts disease recurrence within 5 years after retrograde intrarenal surgery. Even small residual fragments are an important risk factor for future stone-related (ipsilateral) events; therefore, patients with residual fragments of any size should not be labeled "stone-free" and endoscopic stone treatment should aim at complete stone clearance.
Journal of endourology / Endourological Society. 2016 Mar 28 [Epub ahead of print]
Simon Hein, Arkadiusz Miernik, Konrad Wilhelm, Daniel Schlager, Dominik Stefan Schoeb, Fabian Adams, Vach Werner, Martin Schoenthaler
University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ; University of Freiburg, Centre for Medical Biometry and Medical Informatics, Freiburg, Germany ; University Medical Center Freiburg, Department of Urology, Freiburg, Germany ;