Contamination Rates in Duodenoscopes Reprocessed Using Enhanced Surveillance and Reprocessing Techniques: A Systematic Review and Meta-Analysis

Background/Aims: Multiple outbreaks of multidrug-resistant organisms have been reported worldwide due to contaminated duodenoscopes. In 2015, the United States Food and Drug Administration recommended the following supplemental enhanced surveillance and reprocessing techniques (ESRT) to improve duodenoscope disinfection: 1. microbiological culture, 2. ethylene oxide sterilization, 3. liquid chemical sterilant processing system, and 4. double high-level disinfection. A systematic review and meta-analysis was performed to assess the impact of ESRT on the contamination rates. Methods: A thorough and systematic search was performed across several databases and conference proceedings from inception until January 2021, and all studies reporting the effectiveness of various ESRIs were identified. The pooled contamination rates of post-ESRT duodenoscopes were estimated using the random effects model. Results: A total of seven studies using various ESRTs were incorporated in the analysis, which included a total of 9,084 post-ESRT duodenoscope cultures. The pooled contamination rate of the post-ESRT duodenoscope was 5% (95% confidence interval [CI]: 2.3%-10.8%, inconsistency index [F]=97.97%). Pooled contamination rates for high-risk organisms were 0.8% (95% CI: 0.2%-2.7%, I-2 =94.96). Conclusions: While ESRT may improve the disinfection process, a post-ESRT contamination rate of 5% is not negligible. Ongoing efforts to mitigate the rate of contamination by improving disinfection techniques and innovations in duodenoscope design to improve safety are warranted.