title: Detection and prediction of active tuberculosis disease by a whole-blood interferon-gamma release assay in HIV-1-infected individuals.
abstract: BACKGROUND
  The sensitivity of whole-blood interferon-gamma release assays to detect or predict active tuberculosis in individuals infected with human immunodeficiency virus type 1 (HIV-1) has as yet not been determined. Methods. In this prospective, longitudinal, single-center study, 830 HIV-1-infected patients underwent testing with the QuantiFERON-TB Gold In-Tube (QFT-GIT) assay. Clinical screening for active tuberculosis was performed at least every 3 months for a median follow-up time of 19 months.
  
  
  RESULTS
  At baseline, the QFT-GIT assay yielded positive or indeterminate results in 44 (5.3%) and 47 (5.7%) of the 830 patients, respectively. A positive QFT-GIT assay result occurred at significantly higher frequencies among black individuals than among white individuals (odds ratio, 4.84; 95% confidence interval, 2.25-9.97; P< .001), among patients from Africa than among patients from Austria (odds ratio, 6.57; 95% confidence interval, 2.99-14.25; P< .001), and among patients from high-prevalence countries than among patients from low-prevalence countries (odds ratio, 5.86; 95% confidence interval, 2.41-13.44; P< .001). In patients with indeterminate QFT-GIT assay results, both median actual and nadir CD4(+) T cell counts were significantly lower than in patients with interpretable QFT-GIT assay results (P< .001). At the time of baseline QFT-GIT screening, active tuberculosis was found in 7 (15.9%) of 44 individuals with a positive result and in 1 (0.1%) of 739 patients with a negative result. During the follow-up period, however, progression to active tuberculosis occurred exclusively in patients with a positive QFT-GIT assay result, at a rate of 8.1% (3 of 37 patients; P< .001). Collectively, the sensitivity of the QFT-GIT assay for active tuberculosis was 90.9% (95% confidence interval, 62.3%-98.4%).
  
  
  CONCLUSIONS
  Our results suggest that the QFT-GIT assay may be a sensitive tool for the detection and prediction of active tuberculosis in HIV-1-infected individuals.
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy, and Infectious Diseases, Vienna General Hospital, Medical University of Vienna, Vienna, Austria.
authors.forename: Maximilian C
authors.initials: MC
authors.lastname: Aichelburg
authors.forename: Armin
authors.initials: A
authors.lastname: Rieger
authors.forename: Florian
authors.initials: F
authors.lastname: Breitenecker
authors.forename: Katharina
authors.initials: K
authors.lastname: Pfistershammer
authors.forename: Julia
authors.initials: J
authors.lastname: Tittes
authors.forename: Stephanie
authors.initials: S
authors.lastname: Eltz
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Aichelburg
authors.forename: Georg
authors.initials: G
authors.lastname: Stingl
authors.forename: Athanasios
authors.initials: A
authors.lastname: Makristathis
authors.forename: Norbert
authors.initials: N
authors.lastname: Kohrgruber
mesh_terms: D000328:Adult; D000349:Africa; D001317:Austria; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000821:virology; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D007371:Interferon-gamma / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D044469:Racial Groups; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D007371:Interferon-gamma