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Updated: Apr 29, 2026
Culturing and Maintaining Clostridium difficile in an Anaerobic Environment
Published on: September 14, 2013
Evaluation of endoscopic processing on the potential for Clostridiodes difficile transmission
D Ramkumar1, M Pezzone2, A Kinzler3
1Infectious Diseases and Microbiology Department, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA.
Introduction:
Clostridiodes difficile is a common healthcare-associated infection. This spore-forming pathogen is difficult to remove from environmental surfaces and equipment. Endoscopes are essential reusable medical equipment for diagnostic and therapeutic indications. The primary aim of this study was to evaluate the efficacy of colonoscopic disinfection in terms of ability to eliminate C. difficile. The secondary aim was to investigate the prevalence of C. difficile colonization, and presence of the toxin in the sample population.
Methods:
A convenience sample of 100 colonoscopic procedures was included. The colonoscopes were flushed with 50 mL of sterile water before and after high-level disinfection (HLD). Both samples were subjected to DNA extraction and quantification, followed by quantitative polymerase chain reaction (qPCR) testing. Electronic health records were reviewed for clinical and demographic information.
Results:
The mean age of patients was 57 years, and the mean duration of colonoscopy was 37 min. One patient was known to have C. difficile infection prior to colonoscopy. Aerobic culture broth was positive in 29% of cases in pre-HLD samples, while no cases were culture positive after HLD. Thirty-one (57.41%) samples were positive by qPCR, and 15 (48.39%) remained positive after HLD. The cycle threshold value and DNA quantification were lower after HLD.
Conclusion:
There is a high prevalence of asymptomatic C. difficile colonization among patients undergoing colonoscopic examination. HLD was effective in reducing, but not eliminating, C. difficile. The presence of a low quantity of DNA cannot be translated to increased risk of transmission, especially with negative cultures.
