Iatrogenic Infection from Endoscopes Despite High-Level Disinfection

Chris E. Forsmark, MD

A recent outbreak highlights the importance and challenges of disinfecting duodenoscopes.

Although multisociety guidelines detail steps for reliable, high-level disinfection (Gastrointest Endosc 2011; 73:1075), inadequately disinfected endoscopes have previously caused clusters of infections.

In a recent investigation of a single-hospital outbreak of carbapenem-resistant Enterobacteriaceae (CRE) producing New Delhi metallo-β-lactamase (NDM) — a pathogen that is rare in the U.S. and marked by high mortality and limited treatment options — the 39 infected patients had all been exposed to a duodenoscope, and 35 had been exposed to a single duodenoscope. An NDM-producing Escherichia coli strain identical to the patients' pathogen was recovered from this duodenoscope even after reprocessing.

A careful analysis identified no lapses in manufacturer-recommended, standard processing of the scope between infected patients. The duodenoscope was not damaged, had undergone routine maintenance, and was 3 years old. Once the hospital switched from high-level disinfection with an automated washer to gas sterilization, cultures obtained from the duodenoscope were negative and no additional patients developed this infection.

Citation(s):

Epstein L et al. New Delhi metallo-β-lactamase–producing carbapenem-resistant Escherichia coli associated with exposure to duodenoscopes. JAMA 2014 Oct 8; 312:1447.

Rutala WA and Weber DJ.Gastrointestinal endoscopes: A need to shift from disinfection to sterilization? JAMA 2014 Oct 8; 312:1405.