Nosocomial transmission of Mycobacterium tuberculosis from an extrapulmonary site

Infect Control Hosp Epidemiol. 2001 Jan;22(1):10-2. doi: 10.1086/501817.


Objective: To assess the extent of nosocomial transmission and risk factors associated with tuberculin skin test (TST) conversions among healthcare workers (HCWs) exposed to a patient with genitourinary Mycobacterium tuberculosis.

Design: Retrospective cohort study of exposed HCWs.

Setting: A 275-bed community hospital in Middle Tennessee.

Participants: A total of 128 exposed HCWs and the index patient, who required drainage of a prostatic abscess and bilateral orchiectomy and expired after a 27-day hospitalization. Disseminated tuberculosis was diagnosed at autopsy.

Methods: Contact tracing was performed on exposed HCWs. Logistic regression was used to identify independent risk factors associated with TST conversion.

Results: A total of 128 HCWs were exposed to the index patient. There was no evidence of active pulmonary tuberculosis throughout the patient's hospitalization; TST conversions occurred only among HCWs who were exposed to the patient during or after his surgical procedures. A total of 12 (13%) of 95 exposed HCWs who were previously nonreactive had newly positive TST: 6 of 28 nurses, 3 of 3 autopsy personnel, 2 of 17 respiratory therapists, and 1 of 12 surgical staff. By logistic regression, irrigation or packing of the surgical site was the only independent risk factor associated with TST conversion among nurses (odds ratio, 9; 95% confidence interval, 1.2-67; P=.03).

Conclusion: Manipulation of infected tissues of the genitourinary tract can result in nosocomial transmission of tuberculosis.

MeSH terms

  • Adult
  • Aged
  • Autopsy
  • Cohort Studies
  • Cross Infection*
  • Female
  • Hospitals, Community
  • Humans
  • Infectious Disease Transmission, Patient-to-Professional*
  • Male
  • Middle Aged
  • Mycobacterium tuberculosis / pathogenicity*
  • Nursing Staff, Hospital
  • Retrospective Studies
  • Risk Factors
  • Tuberculin Test
  • Tuberculosis, Male Genital / microbiology
  • Tuberculosis, Male Genital / transmission*
  • Urogenital System / microbiology