An outbreak of multidrug-resistant Pseudomonas aeruginosa infections following flexible ureteroscopic stone removal.

Abstract

Background: Postoperative infections are an emerging concern in endourology. This study reports an outbreak of urinary tract infections associated with Pseudomonas aeruginosa (PA) in patients who underwent stone removal surgery using flexible ureteroscopy (FURS) at Seoul Medical Center.

Methods: Between August and December 2024, five patients who underwent FURS performed by the same surgeon developed postoperative febrile episodes requiring further treatment. Urine cultures from four patients revealed an outbreak of multidrug-resistant PA, prompting environmental cultures and an inspection of the instrument reprocessing procedures led by the hospital's infection control department.

Results: Although PA was not isolated from the FURS itself, urine culture results showed identical antibiotic susceptibility profiles, and three patients exhibited temporal continuity, suggesting that the infections were related to surgery. No PA infections occurred among patients treated by other surgeons using single-use FURS during the same period, indicating that the infections were associated with the reusable FURS used solely by surgeon A. Environmental culturing detected PA on the sink and handle in the cleaning room, and deficiencies in the reprocessing procedures were identified. The FURS reprocessing protocol was revised to include ethylene oxide gas sterilization after each use, twice-daily disinfections of the sink where PA was identified, and replacement of handles and brushes. After implementing improvements to the reprocessing protocol, no further infections were reported over six months.

Conclusions: Comprehensive device management may help prevent device related outbreaks. Given the complexity of FURS reprocessing, systematic management by trained personnel and ongoing monitoring are necessary to prevent device-associated infections.