title: Prevalence of latent tuberculosis infection in persons with and without human immunodeficiency virus infection using two interferon-gamma release assays and tuberculin skin test in a low human immunodeficiency virus prevalence, intermediate tuberculosis-burden country.
abstract: BACKGROUND
  The risk of tuberculosis (TB) is higher in human immunodeficiency virus (HIV)-infected patients and intravenous drug users (IDUs). We determined the prevalence and risk factors of latent TB infection (LTBI) in individuals with or without HIV infection, including IDUs, in a country with a low HIV prevalence, an intermediate TB burden, and a high Bacillus Calmette-Guérin (BCG) vaccine coverage using two interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST).
  
  
  METHODS
  For this prospective, cross-sectional study, HIV-infected and -uninfected patients from a regional hospital and medical center in Taiwan were enrolled. Results of the two IGRAs [QuantiFERON-TB Gold (QFT-G) and QuantiFERON-TB Gold In-Tube (QFT-GIT)] and the TST were compared. Risk factors for positivity were analyzed.
  
  
  RESULTS
  We recruited 233 patients [198 (85%) men; mean age, 39.4 years]. Most patients (74%) were BCG vaccinated. The prevalence of LTBI was estimated to be 22.8% by TST, 15.9% by QFT-G, and 20.6% by QFT-GIT. HIV-infected individuals had fewer positive QFT-GIT [7.0% vs. 28.6%, p < 0.001, adjusted odds ratio (aOR) = 0.28, p = 0.05] and TST results, and more indeterminate QFT-G responses (9.3% vs. 0.7%, p = 0.002). Concordance between IGRAs and TST was very poor in HIV-infected patients (κ < 0.05). Independent risk factors for IGRA positivity were increasing age (QFT-G: aOR = 1.98, p = 0.03; QFT-GIT: aOR = 2.00, p = 0.01) and IDUs (aOR = 4.33, p = 0.05 by QFT-G).
  
  
  CONCLUSIONS
  HIV-infected persons had a significantly lower response to both IGRAs and TST. High discordance was found between the two generations of IGRAs and between IGRAs and TST. Increasing age, a known risk factor for LTBI, was significantly associated with IGRAs, but not with TST.
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Wei-Cheng
authors.initials: WC
authors.lastname: Lin
authors.affiliation: Department of Internal Medicine and Infection Control, E-Da Hospital/I-Shou University, Kaohsiung, Taiwan.
authors.forename: Hsi-Hsun
authors.initials: HH
authors.lastname: Lin
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan. Electronic address: ssjlee28@yahoo.com.tw.
authors.forename: Susan Shin-Jung
authors.initials: SS
authors.lastname: Lee
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Cheng-Len
authors.initials: CL
authors.lastname: Sy
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Kuan-Sheng
authors.initials: KS
authors.lastname: Wu
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jui-Kuang
authors.initials: JK
authors.lastname: Chen
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hung-Chin
authors.initials: HC
authors.lastname: Tsai
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yao-Shen
authors.initials: YS
authors.lastname: Chen
mesh_terms: D000328:Adult; D001500:BCG Vaccine / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D059425:Interferon-gamma Release Tests / Q000379:methods*; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology*; D008297:Male; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D013624:Taiwan / Q000453:epidemiology; D014374:Tuberculin Test; D014611:Vaccination / Q000706:statistics & numerical data
chemical_list: D001500:BCG Vaccine
keywords: QuantiFERON; human immunodeficiency virus; interferon-γ release assay; intravenous drug users; latent tuberculosis; tuberculin skin test