title: IFN-γ Release Assay Result Is Associated with Disease Site and Death in Active Tuberculosis.
abstract: The IFN-γ release assays and tuberculin skin tests are used to support the diagnosis of both latent and active tuberculosis. However, we previously demonstrated that a negative tuberculin test in active tuberculosis is associated with disseminated disease and death. It is unknown whether the same associations exist for IFN-γ release assays.
  
  
  
  To determine the association between these tests and site of tuberculosis and death among persons with active tuberculosis.
  
  
  
  We analyzed IFN-γ release assays and tuberculin test results for all persons with culture-confirmed tuberculosis reported to the U.S. National Tuberculosis Surveillance System from 2010 to 2014. We used logistic regression to calculate the association between these tests and site of disease and death.
  
  
  
  A total of 24,803 persons with culture-confirmed tuberculosis had either of these test results available for analysis. Persons with a positive tuberculin test had lower odds of disseminated disease (i.e., miliary or combined pulmonary and extrapulmonary disease), but there was no difference in the odds of disseminated disease with a positive IFN-γ release assay. However, persons who were positive to either of these tests had lower odds of death. An indeterminate IFN-γ release assay result was associated with greater odds of both disseminated disease and death.
  
  
  
  Despite perceived equivalence in clinical practice, IFN-γ release assays and tuberculin test results have different associations with tuberculosis site, yet similar associations with the risk of death. Furthermore, an indeterminate IFN-γ release assay result in a person with active tuberculosis is not unimportant, and rather carries greater odds of disseminated disease and death. Prospective study may improve our understanding of the underlying mechanisms by which these tests are associated with disease localization and death.
authors: 1 Division of Pulmonary and Critical Care Medicine, Emory University School of Medicine, Atlanta, Georgia.
authors: Sara C
authors: SC
authors: Auld
authors: 2 Center for Surveillance, Epidemiology, and Laboratory Services.
authors: Scott H
authors: SH
authors: Lee
authors: 3 Division of Global HIV/Tuberculosis, and.
authors: Eleanor S
authors: ES
authors: Click
authors: 4 Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors: Roque
authors: R
authors: Miramontes
authors: 5 Emory Vaccine Center and Department of Microbiology, Emory University, Atlanta, Georgia; and.
authors: Cheryl L
authors: CL
authors: Day
authors: 6 Departments of Epidemiology, Global Health, and Medicine, Emory University Rollins School of Public Health and School of Medicine, Atlanta, Georgia.
authors: Neel R
authors: NR
authors: Gandhi
authors: 2 Center for Surveillance, Epidemiology, and Laboratory Services.
authors: Charles M
authors: CM
authors: Heilig
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D059425:Interferon-gamma Release Tests; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D062486:Public Health Surveillance; D012189:Retrospective Studies; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis* / Q000401:mortality*; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: Mycobacterium tuberculosis; public health surveillance; tuberculin test