Detection and Prediction of Active Tuberculosis Disease by a Whole-Blood Interferon-γ Release Assay in HIV-1–Infected Individuals

• Published in: Clinical infectious diseases Vol. 48; no. 7; pp. 954 - 962
• Main Authors: Aichelburg, Maximilian C., Rieger, Armin, Breitenecker, Florian, Pfistershammer, Katharina, Tittes, Julia, Eltz, Stephanie, Aichelburg, Alexander C., Stingl, Georg, Makristathis, Athanasios, Kohrgruber, Norbert
• Format: Journal Article
• Language: English
• Published: Oxford The University of Chicago Press 01.04.2009; University of Chicago Press; Oxford University Press
• Subjects: Adult; Africa; AIDS; Antiretrovirals; Austria; Bacterial diseases; Biological and medical sciences; CD4 Lymphocyte Count; Continental Population Groups; Cutaneous tuberculosis; Female; HIV Infections - complications; HIV Infections - virology; HIV-1 - isolation & purification; HIV/AIDS; Human bacterial diseases; Human viral diseases; Humans; Immunodeficiencies; Immunodeficiencies. Immunoglobulinopathies; Immunopathology; Infections; Infectious diseases; Interferon-gamma - blood; Latent tuberculosis; Longitudinal Studies; Male; Medical sciences; Middle Aged; Mycobacterium tuberculosis; Sensitivity and Specificity; Skin tests; T lymphocytes; Tuberculin; Tuberculosis; Tuberculosis - diagnosis; Tuberculosis and atypical mycobacterial infections; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; Young Adult; Austria; Africa; Infection; Whole blood; Immunopathology; Tuberculosis; Viral disease; Bacteriosis; AIDS; Mycobacterial infection; Predictive factor; Immune deficiency; Release; Gamma interferon
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1086/597351

Background. The sensitivity of whole-blood interferon-γ 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.