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Endoscope storage time: assessment of microbial colonization up to 21 days after reprocessing
Andrew S Brock1, Lisa L Steed2, Janice Freeman1
1Division of Gastroenterology and Hepatology, Medical University of South Carolina, Charleston, South Carolina, USA.
Background:
Insufficient data exist for how long endoscopes can be stored after reprocessing. Concern about possible microbial colonization has led to various recommendations for reprocessing intervals among institutions, with many as short as 5 days. A significant cost savings could be realized if it can be demonstrated that endoscopes may be stored for as long as 21 days without risk of clinically significant contamination.
Objective:
To demonstrate whether flexible endoscopes may be stored for as long as 21 days after reprocessing without colonization by pathogenic microbes.
Design:
Prospective, observational study.
Setting:
Tertiary care center.
Endoscopes:
Four duodenoscopes, 4 colonoscopes, and 2 gastroscopes.
Intervention:
Microbial testing of endoscope channels.
Main Outcome Measurements:
Culture results at days 0, 7, 14, and 21.
Results:
There were 33 positive cultures from 28 of the 96 sites tested (29.2% overall contamination rate). Twenty-nine of 33 isolates were typical skin or environmental contaminants, thus clinically insignificant. Four potential pathogens were cultured, including Enterococcus, Candida parapsilosis, α-hemolytic Streptococcus, and Aureobasidium pullulans; all were likely clinically insignificant as each was only recovered at 1 time point at 1 site, and all grew in low concentrations. There were no definite pathogenic isolates.
Limitations:
Single center.
Conclusion:
Endoscopes can be stored for as long as 21 days after standard reprocessing with a low risk of pathogenic microbial colonization. Extension of reprocessing protocols to 21 days could effect significant cost savings.
Insights
Flexible endoscopes can be stored for 21 days post-reprocessing with minimal risk of pathogenic microbial contamination. This finding supports extending storage intervals, potentially leading to significant cost savings in healthcare settings.
Area of Science:
- Infection Control and Prevention
- Medical Device Reprocessing
- Microbiology
Background:
- Limited data exist on the maximum safe storage duration for reprocessed endoscopes.
- Current reprocessing interval recommendations vary, with many institutions limiting storage to 5 days due to concerns about microbial colonization.
- Extending endoscope storage could offer substantial cost savings.
Purpose of the Study:
- To evaluate the risk of pathogenic microbial colonization in flexible endoscopes stored for up to 21 days after reprocessing.
- To determine if current reprocessing protocols allow for extended endoscope storage without compromising patient safety.
Main Methods:
- A prospective, observational study was conducted at a tertiary care center.
- Microbial testing was performed on channels of various flexible endoscopes (duodenoscopes, colonoscopes, gastroscopes) at 0, 7, 14, and 21 days post-reprocessing.
- Culture results were analyzed to assess microbial colonization rates and identify specific microorganisms.
Main Results:
- A 29.2% overall contamination rate was observed across 96 tested sites.
- The majority of isolates (29/33) were common skin or environmental contaminants, considered clinically insignificant.
- Four potential pathogens were identified but were likely clinically insignificant due to low concentration and single-time point recovery; no definite pathogenic isolates were found.
Conclusions:
- Flexible endoscopes can be stored for up to 21 days after standard reprocessing with a low risk of pathogenic microbial colonization.
- Extending endoscope reprocessing and storage protocols to 21 days is feasible and could result in significant cost efficiencies.
- Further multi-center studies may be warranted to validate these findings across diverse healthcare settings.
