Microbiological monitoring of endoscopes: 5-year review

Periodic microbiological monitoring of endoscopes is a recommendation of the Gastroenterological Society of Australia (GENSA). The aim of monitoring has been to provide quality assurance of the cleaning and disinfection of endoscopes; however, there is controversy regarding its frequency. This lack of consensus stimulated a review of the experience within our health service. At Southern Health, routine microbiological sampling has involved 4-weekly monitoring of bronchoscopes, duodenoscopes and automated flexible endoscope reprocessors (AFER), and 3-monthly monitoring of all other gastrointestinal endoscopes. Records of testing were reviewed from 1 January 2002 until 31 December 2006. A literature review was conducted, cost analysis performed and positive cultures investigated. There were 2374 screening tests performed during the 5-year period, including 287 AFER, 631 bronchoscopes for mycobacteria and 1456 endoscope bacterial screens. There were no positive results of the AFER or bronchoscopes for mycobacteria. Of the 1456 endoscopic bacterial samples, six were positive; however, retesting resulted in no growth. The overall cost of tests performed and cost in time for nursing staff to collect the samples was estimated at $AUD 100,400. Periodic monitoring of endoscopes is both time-consuming and costly. Our review demonstrates that AFER (Soluscope) perform well in cleaning endoscopes. Based on our 5-year experience, assurance of quality for endoscopic use could be achieved through process control as opposed to product control. Maintenance of endoscopes and AFER should be in accordance with the manufacturer's instructions and microbiological testing performed on commissioning, annually and following repair. Initial prompt manual leak testing and manual cleaning followed by mechanical leak testing, cleaning and disinfection should be the minimum standard in reprocessing of endoscopes.