title: A nosocomial outbreak of multidrug-resistant tuberculosis.
abstract: BACKGROUND
  An outbreak of seven cases (in six patients and one health care worker, all of whom had AIDS) of multidrug-resistant tuberculosis occurred in a hospital in Chicago. The hospital had a respirator-fit testing program but no acid-fast bacilli isolation rooms.
  
  
  OBJECTIVE
  To identify risk factors for transmission of Mycobacterium tuberculosis.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Private hospital.
  
  
  METHODS
  Patients and health care workers exposed to M. tuberculosis.
  
  
  METHODS
  Analysis of M. tuberculosis isolates, tuberculin skin testing, assessment of exposure, and assessment of participant characteristics.
  
  
  RESULTS
  All seven M. tuberculosis isolates had matching DNA fingerprints. Of patients exposed to M. tuberculosis, those who developed tuberculosis had lower CD4+ T-lymphocyte counts (P = 0.02) and were more likely to be ambulatory (P = 0.03) than those who did not. Of 74 exposed health care workers, the 11 (15%) who had conversion on tuberculin skin testing were no more likely than those who did not have conversion to report that they always wore a respirator with a high-efficiency particulate air filter.
  
  
  CONCLUSIONS
  Transmission of M. tuberculosis occurred in a hospital that did not have recommended isolation rooms. A respirator-fit testing program did not protect health care workers in this setting.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Kenyon
authors.forename: R
authors.initials: R
authors.lastname: Ridzon
authors.forename: R
authors.initials: R
authors.lastname: Luskin-Hawk
authors.forename: C
authors.initials: C
authors.lastname: Schultz
authors.forename: W S
authors.initials: WS
authors.lastname: Paul
authors.forename: S E
authors.initials: SE
authors.lastname: Valway
authors.forename: I M
authors.initials: IM
authors.lastname: Onorato
authors.forename: K
authors.initials: K
authors.lastname: Castro
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000453:epidemiology* / Q000635:transmission; D002641:Chicago / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000635:transmission; D016172:DNA Fingerprinting; D004196:Disease Outbreaks; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification; D012189:Retrospective Studies; D012307:Risk Factors; D018088:Tuberculosis, Multidrug-Resistant / Q000453:epidemiology* / Q000635:transmission