POST-ERCP INFECTIONS CAUSED BY CONTAMINATED DUODENOSCOPES

Aims Despite compliance to extensive reprocessing protocols, duodenoscopes have been related to multiple outbreaks of multi-drug resistant organisms (MDRO) due to persistent duodenoscope contamination. Reports of duodenoscope associated infections (DAI) usually describe outbreaks of MDRO. Outbreaks with susceptible microorganisms probably do occur, but are hard to recognize and thus underreported. We aim to find all potential DAIs that occurred in a large ERCP center within fifteen months.

Methods This retrospective observational study is partially based on a previous cohort study, in which all duodenoscopes in a tertiary health care center were sampled after reprocessing following ERCP procedures. Between July 2017 and October 2018, 460 duodenoscope samples were collected. This cohort was combined with patient samples. Infection is defined as positive culture from blood or liver bed (bile, drain, abscesses, etc.). Possible DAI was defined as the same microorganism at species level in the duodenoscope and patient culture within one year after the ERCP.

Results Data of 837 ERCPs was available. We found 20 patients (2.4%) with an infection within one year after ERCP with the same microorganism as found on the duodenoscope used during their ERCP. Thirteen of these 20 (65%) infections were gut flora, accounting for 1.6% of all 837 ERCPs. Enterobacter cloacae complex was the most common cultured microorganism (7 cases).

Conclusions We hypothesize that DAIs caused by susceptible microorganisms are still a blind spot in daily practice. In this study, 1.6% of 837 ERCP procedures was associated with an infection with gut flora potentially transmitted by contaminated duodenoscopes based on resemblance at species level. Further molecular typing is needed to definitely match microorganisms found on the duodenoscope with patient samples. These infections caused by exogenous bacteria are potentially preventable as opposed to infections caused by patients´ own flora which are an inherent risk of endoscopic procedures.