title: Evaluation of medically significant bacteria in colonoscopes after 8 weeks of shelf life in open air storage.
abstract: The purpose of this study was to examine bacterial growth in colonoscopes in a series of graduated shelf times. There is no conclusive evidence on the length of time colonoscopes can be safely stored before requiring redisinfection. Standards for processing scopes after use are described and supported by the professional organizations of gastroenterology and infection control; however, shelf life varies from 3 to 5 days and most recommendations are based on clinical consensus. In this study, four colonoscopes were used in a clinical procedure, underwent automated high-level disinfection with 2.6% buffered glutaraldehyde, and cultured after 3, 5, 7, 14, 21, 28, 42, and 56 days of shelf time. Two investigators collected all the cultures after interrater reliability was established. Cultures were processed in the microbiology laboratory. No medically significant growth was detected at any of the culture points. At Day 14 and Day 42, one of four scopes grew fewer than two colony-forming units of a medically insignificant bacterium. Using professional standards for high-level disinfection growth was suppressed for up to 8 weeks. Further evidence to assess fungal or viral growth is needed to be able to make suggestions for colonoscope shelf life.
authors.affiliation: GI Procedure Lab, St. Mary's Medical Center, Evansville, Indiana 47750, USA.
authors.forename: Jackie
authors.initials: J
authors.lastname: Ingram
authors.forename: Peggy
authors.initials: P
authors.lastname: Gaines
authors.forename: Roberta
authors.initials: R
authors.lastname: Kite
authors.forename: Marcia
authors.initials: M
authors.lastname: Morgan
authors.forename: Sheila
authors.initials: S
authors.lastname: Spurling
authors.forename: Rebecca P
authors.initials: RP
authors.lastname: Winsett
mesh_terms: D000388:Air; D001419:Bacteria / Q000254:growth & development*; D020685:Colonoscopes / Q000382:microbiology*; D015169:Colony Count, Microbial / Q000379:methods; D004203:Disinfection / Q000379:methods / Q000592:standards*; D004866:Equipment Contamination / Q000517:prevention & control; D006801:Humans; D007196:Indiana; D008137:Longitudinal Studies; D011446:Prospective Studies; D013997:Time Factors