Establishing a clinically relevant bioburden benchmark: A quality indicator for adequate reprocessing and storage of flexible gastrointestinal endoscopes

Abstract

Microbiological surveillance of patient-ready flexible endoscopes has been suggested as a tool for endoscope reprocessing quality assurance. However, a proper guideline defining the performance and the frequency of monitoring procedures and specifying how to interpret the results is lacking. All channels from the 20 flexible gastrointestinal endoscopes (5 gastroscopes, 9 colonoscopes, and 6 duodenoscopes) used at an endoscopy clinic were tested for the presence of bacteria and fungi early every Monday morning over a 7-month period. Bacteria and fungi were detected in 5.7% of the 383 channels tested. Of the 141 scopes tested, 14.1% had detectable growth in at least 1 channel. No significant relationship was detected between the scope or channel type and detection of microorganisms. Over the 7 months of testing, 99.5% of scope channels consistently demonstrated <100 cfu/mL of microbial growth. Based on our clinical findings, we recommend 100 cfu/mL as a reliable and routinely achievable cutoff for bioburden residuals in reprocessed endoscope channels. This cutoff is the same as the Canadian cutoff for dialysis water.