title: Development and evaluation of a new interferon-gamma release assay for the diagnosis of tuberculosis infection in HIV-infected individuals in China.
abstract: BACKGROUND
  Human immunodeficiency virus (HIV)-infected individuals are at high risk of contracting tuberculosis (TB) disease, and current methods for diagnosing TB infection are less effective in this population. We developed and evaluated a new interferon-gamma release assay (IGRA), named A.TB, in HIV-infected individuals, with and without active TB, in a setting of high TB burden and low HIV prevalence.
  
  
  METHODS
  A total of 255 subjects were divided into 3 groups according to their HIV and TB status: HIV+ without active TB (n = 123), HIV+/TB+ (n = 79), and HIV-/TB+ (n = 65). The A.TB assay was performed in parallel with the QuantiFERON-TB Gold In-Tube (QFT-GIT) and tuberculin skin test (TST).
  
  
  RESULTS
  The positive rate was 59.3% (n = 123) by A.TB and 53.8% (n = 106) by QFT-GIT. We observed a strong concordance of 81.2% (k = 0.612) between the two IGRAs. The QFT-GIT results were affected by low CD4(+) cell count (p = 0.013), while A.TB results were not. A.TB was also performed in patients with active TB (n = 65) and patients with active TB and HIV co-infection (n = 79). The sensitivity of A.TB in these groups was 80.0% and 81.0%, respectively.
  
  
  CONCLUSIONS
  The A.TB results were not affected by low CD4(+) cell count in the co-infected cohort. With further evaluation, A.TB may prove to be a valuable tool for diagnosing TB in HIV-infected patients.
authors.affiliation: From the Vaccine Laboratory, Nankai University , Tianjin , China.
authors.forename: Liang
authors.initials: L
authors.lastname: Yu
authors.forename: Pingzheng
authors.initials: P
authors.lastname: Mo
authors.forename: Zeping
authors.initials: Z
authors.lastname: Wei
authors.forename: Ruiling
authors.initials: R
authors.lastname: Fu
authors.forename: Mai
authors.initials: M
authors.lastname: Yang
authors.forename: Binying
authors.initials: B
authors.lastname: Ji
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Shu
authors.initials: S
authors.lastname: Li
authors.forename: Amie J
authors.initials: AJ
authors.lastname: Strong
authors.forename: Neal
authors.initials: N
authors.lastname: Touzjian
authors.forename: Nicholas
authors.initials: N
authors.lastname: Kushner
authors.forename: Xi-En
authors.initials: XE
authors.lastname: Gui
authors.forename: Yichen
authors.initials: Y
authors.lastname: Lu
authors.forename: Zhongfang
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D000328:Adult; D001431:Bacteriological Techniques / Q000379:methods*; D018791:CD4 Lymphocyte Count; D002681:China / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000276:immunology; D006801:Humans; D059425:Interferon-gamma Release Tests / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014374:Tuberculin Test; D014376:Tuberculosis / Q000150:complications* / Q000175:diagnosis* / Q000276:immunology
keywords: Interferon-gamma release assay; Mycobacterium tuberculosis; human immunodeficiency virus