Multidrug-resistant Pseudomonas aeruginosa cholangitis after endoscopic retrograde cholangiopancreatography: Failure of routine endoscope cultures to prevent an outbreak

BACKGROUND: Nosocomial infections due to medical devices are of increasing concern to infection control practitioners. Attempts to prevent such infections have included surveillance cultures of endoscopes and bronchoscopes. In July 2002, the infectious disease consultation service was asked to see three patients with sepsis due to multidrug-resistant Pseudomonas aeruginosa after endoscopic retrograde cholangiopancreatography (ERCP). OBJECTIVE: To describe an outbreak of multidrug-resistant P. aeruginosa sepsis after ERCP at an institution that performs routine surveillance cultures of endoscopes. DESIGN: A traditional outbreak investigation supplemented by pulsed-field gel electrophoresis (PFGE) was undertaken, including a case-control analysis based on the hypothesis that all infected individuals had their ERCP performed with the same endoscope. SETTING: A tertiary-care academic medical center. RESULTS: The case-control analysis confirmed the hypothesis that undergoing ERCP with the implicated endoscope was associated with a culture positive for Pseudomonas (P = .01). The available strains were identical by PFGE. This outbreak occurred despite a negative surveillance culture of the implicated endoscope 1 month earlier. CONCLUSIONS: Infectious morbidity can occur after endoscopy despite negative surveillance cultures. The practice of routine endoscope cultures does not prevent device-related infectious morbidity.