DS 39 - Transmission of New Delhi Metallo-β-lactamase Producing Escherichia coli Through a Gastroscope From an Esophagogastroduodenoscopy Procedure

Background: Transmission of multi-drug resistant bacteria, such as carbapenem-resistant Enterobacteriaceae (CRE) has been associated with duodenoscopes containing elevator channels. Published data on outbreaks associated with gastroscopes is limited. We investigate the transmission of New Delhi Metallo-β-lactamase producing Escherichia coli (NDM-E.coli) between two hospitalized patients to determine relatedness and potential sources of transmission including a common gastroscope.

Methods: Case study methodology was used and involved collecting the following datasets: chart reviews to determine possible links between two cases occurring July 2023 through September 2023, patient exposures from common scope and environmental proximity, screening specimens collected from rectal samples with isolates sent to the state lab for testing and whole genome sequencing (WGS), infection prevention audits on endoscope cleaning, scope inspections and culturing by a third party.

Results: Both patients had a common gastroscope used, five days apart. The same gastroscope was used on 83 patients prior to sequestering; 44 of whom assented to a screening test. Additionally, 35 patients, admitted to inpatient units common to where the case had been previously hospitalized, were screened. Validation of cleaning and disinfection processes identified no breaches in practice. The scope culture and patient screening results were negative. Third-party inspection found damage to the internal bio channel and insertion tube, suggesting potential causes of contamination.

Conclusions: WGS results indicating genomic linkage and the presence of a similar antimicrobial resistance gene points to a plausible epidemiological linkage to the shared endoscope. Per the Food and Drug Administration (FDA), a sampling and culturing study conducted on newer models of duodenoscopes found a 1.1% reprocessing failure rate with high concern organisms indicating there will always be an inherent risk of infection in procedures using scopes. Health systems must consider gastroscopes as a source of contamination and validate existing.practices. Additional studies need to be performed to assess and decrease this risk.