Skip to main content Accessibility help

Disposable Bronchoscope Model for Simulating Endoscopic Reprocessing and Surveillance Cultures

  • Mohamed H. Yassin (a1) (a2), Rahman Hariri (a3), Yasir Hamad (a1), Juliet Ferrelli (a2), Leeanna McKibben (a4) and Yohei Doi (a1)...



Endoscope-associated infections are reported despite following proper reprocessing methods. Microbiological testing can confirm the adequacy of endoscope reprocessing. Multiple controversies related to the method and interpretation of microbiological testing cultures have arisen that make their routine performance a complex target.


We conducted a pilot study using disposable bronchoscopes (DBs) to simulate different reprocessing times and soaking times and to compare high-level disinfection versus ethylene oxide sterilization. We also reviewed the time to reprocessing and duration of the procedures.


Bronchoscopes were chosen because an alternative disposable scope is commercially available and because bronchoscopes are more prone to delays in processing. Disposable bronchoscopes were contaminated using a liquid bacterial suspension and were then incubated for 1–4 hours. Standard processing and high-level disinfection were performed on 36 endoscopes. Ethylene oxide sterilization was performed on 21 endoscopes. Endoscope cultures were performed using the standard “brush, flush, brush” technique.


After brushing was performed, a final water-flush culture procedure was the most effective method of detecting bacterial persistence on the disposable scopes. Klebsiella pneumoniae was the most commonly recovered organism after reprocessing. Ethylene oxide sterilization did not result in total elimination of viable bacteria.


Routine endoscopy cultures may be required to assess the adequacy of endoscopic processing.

Infect Control Hosp Epidemiol 2017;38:136–142


Corresponding author

Address correspondence to Mohamed H Yassin, MD, PhD, 1400 Locust Street, Pittsburgh, PA 15219, (


Hide All

PREVIOUS PRESENTATION. This study was presented as abstract number 110 at IDWeek 2015 in San Diego, California. The oral abstract session was held on October 8, 2015.



Hide All
1. Banerjee, S, Shen, B, Nelson, D, et al. ASGE Standards of Practice. Infection control during GI endoscopy. Gastrointest Endosc 2008;67:781790.
2. Boudabbous, M, Amouri, A, Mnif, L, Tahri, N. Gastro Endosc Infect 2010;39:887894.
3. Hookey, L, Armstrong, D, Enns, R, Matlow, A, Singh, H, Love, J. Summary of guidelines for infection prevention and control for flexible gastrointestinal endoscopy. Can J Gastroenterol 2013;27:347350.
4. Guideline for disinfection and sterilization in healthcare facilities. 2008. Centers for Disease Control and Prevention website. Published 2008. Accessed December 12, 2015.
5. Society of Gastroenterology Nurses, Associates. Standards of infection control in reprocessing of flexible gastrointestinal endoscopes. Gastroenterol Nurs 2013;36:293303.
6. Jorgensen, SB, Bojer, MS, Boll, EJ, et al. Heat-resistant, extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in endoscope-mediated outbreak. J Hosp Infect 2016;93:5762.
7. Marsh, JW, Krauland, MG, Nelson, JS, et al. Genomic epidemiology of an endoscope-associated outbreak of Klebsiella pneumoniae carbapenemase (KPC)–producing K. pneumoniae . PLoS One 2015;10:e0144310.
8. Ofstead, CL, Wetzler, HP, Doyle, EM, et al. Persistent contamination on colonoscopes and gastroscopes detected by biologic cultures and rapid indicators despite reprocessing performed in accordance with guidelines. Am J Infect Control 2015;43:794801.
9. Kovaleva, J, Meessen, NE, Peters, FT, et al. Is bacteriologic surveillance in endoscope reprocessing stringent enough? Endoscopy 2009;41:913916.
10. Gastmeier, P, Vonberg, RP. Klebsiella spp. in endoscopy-associated infections: we may only be seeing the tip of the iceberg. Infection 2014;42:1521.
11. Srinivasan, A, Wolfenden, LL, Song, X, et al. An outbreak of Pseudomonas aeruginosa infections associated with flexible bronchoscopes. N Engl J Med 2003;348:221227.
12. Kovaleva, J, Peters, FT, van der Mei, HC, Degener, JE. Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy. Clin Microbiol Rev 2013;26:231254.
13. Epstein, L, Hunter, JC, Arwady, MA, et al. New Delhi metallo-beta-lactamase-producing carbapenem-resistant Escherichia coli associated with exposure to duodenoscopes. JAMA 2014;312:14471455.
14. RE: Information regarding the procedure for performing a presoak in detergent solution for cases of delayed reprocessing and excessive bleeding for use with Olympus flexible endoscopes. Olympus website. Published 2014. Accessed March 28, 2016.
15. Gazdik, MA, Coombs, J, Burke, JP, Lopansri, BK. Comparison of two culture methods for use in assessing microbial contamination of duodenoscopes. J Clin Microbiol 2016;54:312316.
16. Ambu aScope 3. Ambu website. Published 2015. Accessed December 14, 2015.
17. Muscarella, LF. Evaluation of the risk of transmission of bacterial biofilms and Clostridium difficile during gastrointestinal endoscopy. Gastroenterol Nurs 2010;33:2835.
18. Kawata, N, Tanaka, M, Kakushima, N, et al. The low incidence of bacteremia after esophageal endoscopic submucosal dissection (ESD) obviates the need for prophylactic antibiotics in esophageal ESD. Surg Endoscopy 2016 Mar 16. [Epub ahead of print].
19. Thosani, N, Zubarik, RS, Kochar, R, et al. Prospective evaluation of bacteremia rates and infectious complications among patients undergoing single-operator choledochoscopy during ERCP. Endoscopy 2016;48:424431.
20. Ribeiro, MM, de Oliveira, AC. Analysis of the air/water channels of gastrointestinal endoscopies as a risk factor for the transmission of microorganisms among patients. Am J Infect Control 2012;40:913916.
21. Schnabel, RM, Van der Velden, K, Osinski, A, Rohde, G, Roekaerts, PM, Bergmans, DC. Clinical course and complications following diagnostic bronchoalveolar lavage in critically ill mechanically ventilated patients. BMC Pulmon Med 2015;15:107115.
22. Rutala, WA, Weber, DJ. Gastrointestinal endoscopes: a need to shift from disinfection to sterilization? JAMA 2014;312:14051406.
23. Design of endoscopic retrograde cholangiopancreatography (ERCP) duodenoscopes may impede effective cleaning: FDA Safety Communication. US Food and Drug Administration website. Published February 2015. Accessed March 4, 2015.
24. FDA recommends health care facilities transition from custom ultrasonics endoscope washer/disinfectors to alternate reprocessing methods: FDA Safety Communication. US Food and Drug Administration website. Published November 2015. Accessed December 12, 2015.


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed