title: Investigation of healthcare-associated transmission of Mycobacterium tuberculosis among patients with malignancies at three hospitals and at a residential facility.
abstract: BACKGROUND
  Immunocompromised patients have an increased risk of experiencing progression of latent Mycobacterium tuberculosis infection (LTBI) to active tuberculosis (TB) disease. In January 2002, 2 patients with leukemia (Patients 1 and 2) developed pulmonary TB after recent exposure at 3 hospitals (Hospital A, Hospital B, and Hospital C) and at a residential facility for patients with cancer. Neither was known to have LTBI. Within 1 year, 3 other patients with malignancy and TB disease had been identified at these facilities, prompting an investigation of healthcare facility-associated transmission of M. tuberculosis.
  
  
  METHODS
  The authors performed genotypic analysis of the five available M. tuberculosis isolates from patients with malignancies at these facilities, reviewed medical records, interviewed individuals who had identical M. tuberculosis genotypic patterns, and performed tuberculin skin testing (TST) and case finding for possible exposed contacts.
  
  
  RESULTS
  Only Patients 1 and 2 had identical genotypic patterns. Neither patient had baseline TST results available. Patient 1 had clinical evidence of infectiousness 3 months before the diagnosis of TB was ascertained. Among employee contacts of Patient 1, TST conversions occurred in 1 of 59 (2%), 2 of 34 (6%), 2 of 32 (6%), and 0 of 8 who were tested at Hospitals A, B, and C and at the residential facility, respectively. Among the others who were exposed to Patient 1, 1 of 31 (3%), 1 of 30 (3%), 0 of 40 (0%), and 12 of 136 (9%) who were tested had positive TSTs at Hospitals A, B, and C and at the residential facility, respectively.
  
  
  CONCLUSIONS
  Delayed TB diagnosis in 2 patients with leukemia resulted in the transmission of M. tuberculosis to 19 patients and staff at 3 hospitals and a residential facility. Baseline TB screening and earlier clinical recognition of active disease could reduce healthcare facility-associated transmission of M. tuberculosis among patients with malignancy.
authors.affiliation: Epidemic Intelligence Service-State Branch, Division of Applied Public Health Training, Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. joseph.malone@na.amedd.army.mil
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Malone
authors.forename: Kashef
authors.initials: K
authors.lastname: Ijaz
authors.forename: Lauren
authors.initials: L
authors.lastname: Lambert
authors.forename: Louie
authors.initials: L
authors.lastname: Rosencrans
authors.forename: Lynelle
authors.initials: L
authors.lastname: Phillips
authors.forename: Victor
authors.initials: V
authors.lastname: Tomlinson
authors.forename: Michael
authors.initials: M
authors.lastname: Arbise
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Moolenaar
authors.forename: Mark S
authors.initials: MS
authors.lastname: Dworkin
authors.forename: Eduardo J
authors.initials: EJ
authors.lastname: Simoes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D016358:Contact Tracing; D003428:Cross Infection; D005260:Female; D006761:Hospitals; D006801:Humans; D017758:Infectious Disease Transmission, Patient-to-Professional; D017757:Infectious Disease Transmission, Professional-to-Patient; D007938:Leukemia / Q000150:complications / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis; D009369:Neoplasms / Q000150:complications* / Q000382:microbiology; D012112:Residential Facilities; D014397:Tuberculosis, Pulmonary / Q000150:complications / Q000635:transmission*