A Novel Protocol Obviates Endoscope Sampling for Carbapenem-Resistant Enterobacteriaceae: Experience of a Center with a Prior Outbreak.

backgroundNumerous published outbreaks, including one from our institution, have described endoscope-associated transmission of multidrug-resistant organisms (MDROs). Individual centers have adopted their own protocols to address this issue, including endoscope culture and sequestration. Endoscope culturing has drawbacks and may allow residual bacteria, including MDROs, to go undetected after high-level disinfection.

aimTo report the outcome of our novel protocol, which does not utilize endoscope culturing, to address our outbreak.

methodsAll patients undergoing procedures with elevator-containing endoscopes were asked to permit performance of a rectal swab. All endoscopes underwent high-level disinfection according to updated manufacturer's guidance. Additionally, ethylene oxide (EtO) sterilization was done in the high-risk settings of (1) positive response to a pre-procedure risk stratification questionnaire, (2) positive or indeterminate CRE polymerase chain reaction (PCR) from rectal swab, (3) refusal to consent for PCR or questionnaire, (4) purulent cholangitis or infected pancreatic fluid collections. Two endoscopes per weekend were sterilized on a rotational basis.

resultsFrom September 1, 2015 to April 30, 2016, 556 endoscopy sessions were performed using elevator-containing endoscopes. Prompted EtO sterilization was done on 46 (8.3%) instances, 3 from positive/indeterminate PCR tests out of 530 samples (0.6%). No CRE transmission was observed during the study period. Damage or altered performance of endoscopes related to EtO was not observed.

conclusionIn this pilot study, prompted EtO sterilization in high-risk patients has thus far eliminated endoscope-associated MDRO transmission, although no CRE infections were noted throughout the institution during the study period. Further studies and a larger patient sample will be required to validate these findings.