Optimizing duodenoscope reprocessing: rigorous assessment of a culture and quarantine protocol

Background and aims: Iatrogenic infections related to duodenoscopes remain a top concern for medical centers where ERCP is performed. We assessed the long-term results and impact of key interventions in the optimization of a rigorous "culture and quarantine" program for duodenoscope reprocessing.

Methods: We reviewed a prospectively collected, quality assurance database of all duodenoscope cultures (n = 4307) obtained for the initial 3-year duration of culture and quarantine from 2014 to 2017 in a single U.S.-based, high-volume endoscopy center. All duodenoscopes were subject to manual cleaning and automated reprocessing and drying, followed by sampling using a modified protocol developed by the Centers for Disease Control and Prevention. Duodenoscopes were cultured per-use.

Results: A total of 4307 duodenoscope cultures were obtained during the study period. High-concern organisms were isolated from 33 of these cultures, resulting in a .697% high-level disinfection defect rate. Statistically significant interventions included withdrawal of a high-frequency culture-positive duodenoscope (scope A) from clinical service in addition to implementation of new manufacturer-recommended cleaning protocols. Withdrawal of a second high-frequency culture-positive duodenoscope (scope B) and a mandatory device retrofit had no effect on the observed rate of positive duodenoscope cultures.

Conclusions: Withdrawal of duodenoscopes with a high rate of culture positivity and optimizing manual cleaning practices have contributed to an overall decline in the high-level disinfection defect rate. A stringent culture and quarantine protocol allowed identification of the culprit endoscopes. There remains a much-needed role for an inexpensive and highly reliable method to check on the adequacy of reprocessing given the inherent complexity of these tasks.