Study Examines Storage Time of Endoscopes

The May issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE), features a study, "Endoscope storage time: assessment of microbial colonization up to 21 days after reprocessing," reporting that, in some cases, it may be safe to store endoscopes longer than five days after reprocessing.

Medical devices and instruments that are not disposable are thoroughly cleaned and disinfected after use to prevent passing infections from one patient to another. For some of these pieces of equipment, there is concern about possible microbial colonization on or in the device even after it has been cleaned and stored. For endoscopes, at least high-level disinfection is recommended by the ASGE and other professional societies, and is achieved through a multi-step system referred to as reprocessing. Endoscopes are hung in special drying environments after cleaning to inhibit growth of bacteria. However, data are insufficient to recommend definitively how long endoscopes can be stored after reprocessing.

Hospitals and other healthcare centers determine their own reprocessing intervals, with many as short as five days. The researchers in this study sought to determine whether flexible endoscopes may be stored for as long as 21 days after reprocessing without colonization by pathogens.

At a tertiary-care center, researchers studied four duodenoscopes, four colonoscopes, and two gastroscopes after reprocessing and hanging. They performed microbial testing of multiple sites on each scope, obtaining cultures on the day of reprocessing, then seven, 14 and 21 days later.

There were 33 positive cultures from 28 of the 96 sites tested (29.2 percent 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 one time point at one site, and all grew in low concentrations. There were no definite pathogenic isolates.

Although the single-center study was limited in size, the results were consistent with previous studies showing insignificant microbial colonization beyond five days of storage. The authors concluded that 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 translate to significant cost savings.

To read the article:

There have been reports of transmission of multidrug-resistant bacteria in specific types of endoscopes. The ASGE has recommended that institutions have additional protocols in place for these types of endoscopes, in addition to standard reprocessing, to prevent transmission of these multidrug-resistant bacteria. 

To access the Multisociety guideline on reprocessing flexible gastrointestinal endoscopes, 2011, CLICK HERE

See the ASGE Interim Guidance at:

Source: American Society for Gastrointestinal Endoscopy (ASGE)