A 21st century nosocomial issue with endoscopes

On 3 January 2014 the results of a year long investigation by the US Centers for Disease Control (CDC) into an outbreak of New Delhi metallo-β-lactamase (NDM)-producing carbapenem resistant Enterobacteriaceae (CRE) were released. Of 69 patients with confirmed CRE infections, 29 went to Advocate Lutheran General Hospital (ALGH) for the same procedure—an endoscopy.1 The endoscopy itself is not dangerous, but the current cleaning process used between procedures leaves patients susceptible to infection and troubles many healthcare practitioners.

With more than 18.6 million gastrointestinal endoscopies and at least a half million bronchoscopies every year in the US alone,2 medical practitioners must take the utmost care during the cleaning process between patients, especially with the emergence of superbugs such as CRE. But the safety profiles of the cleaning protocols are less than acceptable in preventing life threatening outbreaks. The endoscopes are frequently the means for facilitating pathogenic cross contamination between patients—making the case at ALGH far from unique.

The threat of cross contamination may not be visible to a clinician from personal experience alone, but broader and more comprehensive studies show that the cleanliness of endoscopes varies greatly. A mid 2013 study reported that about 15% of endoscopes in US hospitals failed to achieve an accepted standard of cleanliness after liquid reprocessing (the prevailing disinfection process used between patient procedures).3 In this study, duodenoscopes were the dirtiest at a 30% contamination rate, and colonoscopes were the cleanest at a 3% contamination rate.3

All in all, reprocessing is time consuming, labor intensive, expensive and, most importantly, susceptible to failure. Among the most problematic features of an endoscope are the luminal channels, which often become contaminated by endoscope accessories.4 …