Mycobacterium abscessus pseudoinfection traced to an automated endoscope washer: utility of epidemiologic and laboratory investigation.

After 15 patients had positive cultures for Mycobacterium abscessus without evidence of infection (i.e., pseudoinfection) following endoscopy, retrospective cohort studies of patients undergoing endoscopy and microbiologic sampling of the environment were done to examine potential nosocomial transmission and to identify the source and risk factors for M. abscessus pseudoinfection. In the epidemic period, M. abscessus-positive cultures were significantly more likely to be obtained during bronchoscopy than gastroendoscopy (16/149 vs. 1/860, P < .001) and during procedures using bronchoscopes disinfected in an automated washer rather than by other methods (16/54 vs. 0/95, P < .001). M. abscessus was recovered from the automated washer, the inlet water feeding the washer, and a flexible bronchoscope. Environmental and case-patient isolates had identical large restriction fragment (LRF) patterns of genomic DNA separated by pulsed-field gel electrophoresis. Molecular typing using LRF analysis supported the epidemiologic results and demonstrate the utility of combined epidemiologic and laboratory investigations in nosocomial outbreaks of nontuberculous mycobacteria.

[1]  C. Alvarado,et al.  Nosocomial infections from contaminated endoscopes: a flawed automated endoscope washer. An investigation using molecular epidemiology. , 1991, The American journal of medicine.

[2]  V. Pryor,et al.  Outbreak of Mycobacterium chelonae infection associated with use of jet injectors. , 1990, JAMA.

[3]  R. Wallace,,et al.  Large DNA restriction fragment polymorphism in the Mycobacterium avium-M. intracellulare complex: a potential epidemiologic tool , 1993, Journal of clinical microbiology.

[4]  M. Salfinger,et al.  Pseudoepidemic of nontuberculous mycobacteria due to a contaminated bronchoscope cleaning machine. Report of an outbreak and review of the literature. , 1992, Chest.

[5]  P. W. Wheeler,et al.  Bronchopulmonary cross-colonization and infection related to mycobacterial contamination of suction valves of bronchoscopes. , 1989, The Journal of infectious diseases.

[6]  R. Wallace,,et al.  Mycobacterium chelonae causing otitis media in an ear-nose-and-throat practice. , 1988, The New England journal of medicine.

[7]  Fred Silverstein,et al.  Transmission of Infection by Gastrointestinal Endoscopy and Bronchoscopy , 1993, Annals of Internal Medicine.

[8]  L. Bland,et al.  Mycobacterium chelonae wound infections after plastic surgery employing contaminated gentian violet skin-marking solution. , 1987, The New England journal of medicine.

[9]  R. Good,et al.  Identification of clinically significant Mycobacterium fortuitum complex isolates , 1981, Journal of clinical microbiology.

[10]  K. Rolston,et al.  Pseudoepidemic of Mycobacterium fortuitum in bone marrow cultures. , 1987, American journal of infection control.

[11]  Yansheng Zhang,et al.  Contamination of flexible fiberoptic bronchoscopes with Mycobacterium chelonae linked to an automated bronchoscope disinfection machine. , 1992, The American review of respiratory disease.

[12]  R. Wallace,,et al.  Large restriction fragment patterns of genomic Mycobacterium fortuitum DNA as strain-specific markers and their use in epidemiologic investigation of four nosocomial outbreaks , 1992, Journal of clinical microbiology.