title: The association of smoking with IGRA and TST results in HIV-1-infected subjects.
abstract: OBJECTIVE
  To assess the association of smoking with the interferon-gamma (IFN-γ) release assay and tuberculin skin test (TST) results in a comparative study on the detection of latent tuberculous infection (LTBI) in human immunodeficiency virus (HIV) 1-infected individuals.
  
  
  METHODS
  In this cross-sectional study, 305 HIV-1-infected subjects were tested by the QuantiFERON-TB Gold In-Tube assay (QFT-GIT) and the TST. We evaluated the impact of smoking and other LTBI risk factors on QFT-GIT and TST results. RESULTS The concordance of both tests was 93% (κ = 0.71, P < 0.001). The following independent risk factors for both QFT-GIT and TST positivity were identified: birth in a high TB incidence country, self-reported contact with an active TB case and elevated CD4(+) T-cell count (P < 0.001). While smoking was not independently associated with a positive QFT-GIT (OR 1.2, 95%CI 0.5-2.8) or TST result (OR 1.8, 95%CI 0.6-5.9), there was an inverse correlation of the number of cigarettes smoked with IFN-γ levels measured using QFT-GIT (ρ = -0.14, P = 0.027). In addition, smoking was independently associated with a quantitative QFT-GIT response in linear regression analysis (β = 0.129, P = 0.025).
  
  
  CONCLUSIONS
  Although smoking may have a minor inhibitory effect on QFT-GIT response, QFT-GIT results seem not to be affected by smoking to a clinically significant extent.
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: M C
authors.initials: MC
authors.lastname: Aichelburg
authors.affiliation: Department of Internal Medicine III, Division of Gastroenterology & Hepatology, Vienna HIV & Liver Study Group, Medical University of Vienna, Vienna, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Mandorfer
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: J
authors.initials: J
authors.lastname: Tittes
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: F
authors.initials: F
authors.lastname: Breitenecker
authors.affiliation: Department of Internal Medicine III, Division of Gastroenterology & Hepatology, Vienna HIV & Liver Study Group, Medical University of Vienna, Vienna, Austria.
authors.forename: T
authors.initials: T
authors.lastname: Reiberger
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Rieger
authors.affiliation: Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, Vienna, Austria.
authors.forename: N
authors.initials: N
authors.lastname: Kohrgruber
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D016009:Chi-Square Distribution; D060085:Coinfection; D003430:Cross-Sectional Studies; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D059425:Interferon-gamma Release Tests; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D014374:Tuberculin Test