Mycobacterium gordonae in fiberoptic bronchoscopes.
BACKGROUND
Failure of high-level disinfection of bronchoscopes has caused several outbreaks of nosocomial infection or pseudoinfection involving mycobacteria.


METHODS
Inocula (10(5) colony-forming units/ml and 10(8) colony-forming units/ml) of a clinical Mycobacterium gordonae isolate were used to contaminate bronchoscopes. Glutaraldehyde, iodophor, and peracetic acid disinfectants were evaluated in manual and automated disinfection procedures after 10- to 20-minute exposures at 20 degrees and > or = 25 degrees C.


RESULTS
Four of five manual disinfectant procedures failed to eliminate experimental M. gordonae infection after 10-minute exposure at 20 degrees C. All five manual procedures tested at 20 degrees C were effective after 20-minute exposure to the five disinfectants (two 2% alkaline glutaraldehyde preparations, 3.2% alkaline glutaraldehyde, 75 ppm iodophor, and 0.5% glutaraldehyde-0.03% phenolic). Three of four manual (one 2% glutaraldehyde, 3.2% glutaraldehyde, and 0.5% glutaraldehyde-0.03% phenolic) and three automated (one 2% glutaraldehyde, 0.5% glutaraldehyde-0.03% phenolic, and 0.2% peracetic acid) disinfectant procedures eliminated contamination after a 10- to 12-minute exposure at > or = 25 degrees C. Effective total cycle times for the three automated procedures ranged from 20 to 45 minutes.


CONCLUSIONS
Previously Environmental Protection Agency-approved tuberculocidal agents may be ineffective against M. gordonae when used according to label claims under normal clinical conditions. A minimum 20-minute exposure time at 20 degrees C is necessary for manual disinfection methods. Higher temperatures may improve disinfectant efficacy. Newer automatic disinfection machines may be as effective as traditional manual methods and also may reduce hazards to employees.
Jackson
J
J
Department of Medical Education, Providence Medical Center, Portland, OR 97213, USA.
Leggett
J E
JE
Wilson
D A
DA
Gilbert
D N
DN
D020680:Bronchoscopes; D001999:Bronchoscopy; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods* / Q000592:standards; D005336:Fiber Optic Technology; D005976:Glutaral / Q000494:pharmacology; D006801:Humans; D007466:Iodophors / Q000494:pharmacology; D009161:Mycobacterium / Q000187:drug effects*; D009164:Mycobacterium Infections / Q000209:etiology / Q000517:prevention & control*; D010463:Peracetic Acid / Q000494:pharmacology; D013997:Time Factors; D014481:United States
D004202:Disinfectants; D007466:Iodophors; D010463:Peracetic Acid; D005976:Glutaral