Predictive risk factors of urinary tract infection following flexible ureteroscopy despite preoperative precautions to avoid infectious complications

Purpose Urinary tract infection (UTI) is a common complication after flexible ureteroscopy (fURS) despite technical precautions to avoid infectious complications. The aim was to investigate incidence and predictive risk factors of UTI following fURS procedure. Patients and methods We conducted a retrospective study including consecutive fURS performed in our center from January 2015 to March 2019. The indications were: nephrolithiasis management and diagnosis and conservative treatment of upper urinary tract urothelial carcinomas (UTUC). Since 2015, we had technical precautions to avoid postoperative infectious complications: centralized collection of preoperative urine cultures which are examined daily by an urologist and a service provider, systematic use of ureteral access sheath and application of standardized antibiotic prophylaxis measures. The primary endpoint was occurrence of UTI within 15 days following fURS. Results Six hundred and four fURS were included for nephrolithiasis (n = 462) and UTUC management (n = 142). The median (IQR) age in the study cohort was 61(48-68) years, 268 female patients were included (44.4%), the median (IQR) Charlson score was 2(1-4) and single-use fURS were used in 186 cases (30.8%). Postoperative UTI occurred in 41 cases (6.7%). In multivariate analysis, female gender (OR 2.20 [1.02-5.02], p = 0.04), UTI within the last 6 months (OR 2.34 [1.12-5.11], p = 0.02), preoperative polymicrobial urine culture (OR 4.53 [1.99-10.56], p < 0.001) and increased operative time (OR 1.02 [1.002-1.031], p = 0.02) remain associated with postoperative UTI. Conclusions In a large cohort study, female gender, prior UTI, increased operative time and preoperative polymicrobial urine culture were associated with the occurrence of postoperative UTI. Limiting operative time and improving our knowledge of polymicrobial urine cultures could reduce the infectious risk.