title: Antibiotic susceptibility of glutaraldehyde-tolerant Mycobacterium chelonae from bronchoscope washing machines.
abstract: BACKGROUND
  Contamination of bronchoalveolar lavage fluid is a major problem in the world. Although 2% glutaraldehyde (GA) is widely used as a disinfectant for bronchoscope cleaning, recently, GA-tolerant mycobacteria have been isolated, which makes this problem more complicated.
  
  
  METHODS
  We studied the susceptibility to GA and antibiotics of mycobacteria isolated from bronchoscope washing machines in our hospital. We also studied the minimum inhibitory concentrations of GA and antibiotics with pump inhibitors.
  
  
  RESULTS
  Twenty-nine mycobacteria were isolated, of which 26 were Mycobacterium chelonae. Among 18 isolates of M chelonae, excluding 8 isolates in which some results were not reproducible, 50% (9 of 18) were 2% GA-tolerant. One hundred percent (9 of 9) of the GA-tolerant isolates and 11% (1 of 9) of the GA-sensitive isolates were either resistant or intermediately resistant to 2 or 3 classes of antibiotics. Efflux pump inhibitors did not influence the susceptibility to GA and antibiotics.
  
  
  CONCLUSIONS
  It was suggested that there might be an association of GA tolerance with antibiotic resistance in M chelonae. There may a different mechanism(s) other than that involving efflux pumps with regard to GA tolerance and antibiotic resistance in M chelonae. When bronchoscopy-related mycobacterial infections are suspected, physicians and clinical microbiologists should exercise care in handling GA-tolerant mycobacteria, which may be resistant to multiple antibiotics.
authors.affiliation: Department of Microbiology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
authors.forename: Kazuyo
authors.initials: K
authors.lastname: Nomura
authors.forename: Midori
authors.initials: M
authors.lastname: Ogawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyamoto
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Muratani
authors.forename: Hatsumi
authors.initials: H
authors.lastname: Taniguchi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D020680:Bronchoscopes; D004202:Disinfectants; D024881:Drug Resistance, Bacterial; D004866:Equipment Contamination; D005976:Glutaral / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009165:Mycobacterium Infections, Nontuberculous / Q000517:prevention & control; D016926:Mycobacterium chelonae / Q000187:drug effects* / Q000302:isolation & purification*; D012680:Sensitivity and Specificity
chemical_list: D000900:Anti-Bacterial Agents; D004202:Disinfectants; D005976:Glutaral