Scope Contaminations Higher Than Previously Estimated

By Christine Kern, contributing writer

Scopes often remain contaminated despite standard cleaning procedures.

It was determined the problem with the Olympus duodenoscopes linked to the outbreak of superbug infections was the scope’s design made them difficult to clean. Problems continued to plague the manufacturer, even as it announced a recall and redesign of the affected scopes which had been linked to a number of deaths and illnesses.

Now a study published in the American Journal of Infection Control demonstrates the problem with scopes may be far more widespread than previously estimated. According to the research, approved disinfection procedures are ineffective at rendering medical scopes free of infectious bacteria.

According to the Food and Drug Administration, as many as 350 patients at 41 medical facilities across the world were infected or exposed to tainted gastrointestinal scopes between January 1, 2010 and October 31, 2015. A separate Senate investigation discovered 250 scope-related infections at 25 hospitals and clinics worldwide between 2012 and 2015.

Of the 20 gastroscopes and colonoscopes examined for the study, 12 tested positive for bacterial growth. The findings also demonstrated more than half of the gastroscopes were still contaminated after one cleaning, and 11 percent remained contaminated even after two instances of manually cleaning, two rounds of automated cleaning, and high-level disinfection. 

While this study investigated only colonoscopy and gastroscopes — which many believe are easier to clean than other types of scopes — and only tracked the presences of contamination, not infection, it also revealed serious defects in 17 of the 20 scopes. Damage could be a significant contributing factor to contamination as scratches and dents make it easier to hold bacteria, blood or tissue.

Study authors concluded, “This study demonstrated more rigorous reprocessing practices may not be sufficient to ensure that patient-ready endoscopes are free from residual contamination, particularly when the endoscope has defects that could harbor organic debris and biofilm.” In fact, the authors write, “Visual inspection and routine monitoring for biochemical markers of residual contamination may be essential to identify suboptimal reprocessing and proactively identify endoscopes in need of repair or refurbishment. Residual fluid found inside endoscopes indicate that current industry standards do not effectively dry endoscopes, which is essential to minimize growth of environmental contaminants and potential pathogens.

“These findings bolster the need for routine visual inspection and cleaning verification tests recommended in new reprocessing guidelines.”