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A Novel Protocol Obviates Endoscope Sampling for Carbapenem-Resistant Enterobacteriaceae: Experience of a Center with
Zachary L Smith1,2,3, Arshish Dua4, Kia Saeian4,5
1Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA. zlsmith@wustl.edu.
Background:
Numerous 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.
Aim:
To report the outcome of our novel protocol, which does not utilize endoscope culturing, to address our outbreak.
Methods:
All 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.
Results:
From 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.
Conclusion:
In 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.
Insights
This study shows that ethylene oxide sterilization for high-risk patients can prevent multidrug-resistant organism transmission via endoscopes. This method avoids endoscope culturing, addressing a gap in infection control protocols.
Area of Science:
- Infectious Diseases
- Gastroenterology
- Medical Device Sterilization
Background:
- Endoscope-associated transmission of multidrug-resistant organisms (MDROs) is a documented concern.
- Current protocols like endoscope culturing have limitations and may fail to detect residual pathogens.
- Institutions have developed varied strategies to mitigate this risk.
Purpose of the Study:
- To evaluate a novel protocol for preventing endoscope-associated MDRO transmission.
- The protocol omits endoscope culturing and focuses on ethylene oxide (EtO) sterilization for high-risk cases.
Main Methods:
- Patients undergoing procedures with specific endoscopes provided rectal swabs.
- High-level disinfection was standard for all endoscopes.
- Ethylene oxide (EtO) sterilization was prompted for high-risk patients based on questionnaires, PCR results, or clinical conditions.
Main Results:
- Over 556 sessions, 46 instances (8.3%) required prompted EtO sterilization.
- Only 0.6% of rectal swabs yielded positive or indeterminate CRE PCR results.
- No CRE transmission was detected during the study period, and EtO did not damage endoscopes.
Conclusions:
- Prompted EtO sterilization appears effective in eliminating endoscope-associated MDRO transmission in high-risk patients.
- This pilot study suggests a viable alternative to endoscope culturing.
- Larger studies are needed to confirm these promising findings.
