Abstract
Background and study aims The contamination level of ready-to-use endoscopes published in the literature varies
from 0.4 % to 49.0 %. Unfortunately, the comparison and the interpretation of these
results are quite impossible, given the limited number of samples and sites included
and the differences observed between sampling, culturing methods, and interpretation
criteria.
Methods The objective of this retrospective study was to analyze the results of 90,311 endoscope
samples collected between 2004 and 2021 in 490 private or public hospitals in France.
Results Through the full test period, the mean ratio of endoscopes at the action level was
12.6 % (19.5 % including alert level). Of the endoscopy units, 23.0 % had a ratio
of compliant endoscopes ≤ 70.0 %. The overall microbial quality of gastroscopes, duodenoscopes,
and colonoscopes is improving year by year, whereas an opposite trend is observed
for ultrasound endoscopes and bronchoscopes. In 2021, following French guidelines,
13.0 % of the endoscopes should have been quarantined and 8.1 % were at the alert
level, meaning that the contamination level of 21.1 % of the endoscopes exceeded what
was defined as a maximum acceptable value.
Conclusions This study demonstrates that additional efforts, including implementation of microbial
surveillance strategies using a standardized sampling method and periodic observational
audits, must be made to improve the overall microbiological quality of endoscopes
and reduce the risk associated with their use.
