Diagnostic performance of interferon-gamma releasing assay in HIV-infected patients in China

PLoS One. 2013 Aug 2;8(8):e70957. doi: 10.1371/journal.pone.0070957. Print 2013.

Abstract

Background: Active tuberculosis infection represents a very common and significant threat to HIV-infected patients. But measures to accurately detect it are limited.

Objective: To compare and analyze the diagnostic efficacy of T-SPOT.TB alone and in combination with TST in HIV-infected patients in China.

Method: TST (tuberculin skin test) and T-SPOT.TB were performed on 131 HIV-infected patients admitted in Beijing You'an Hospital and Beijing Ditan Hospital between Oct, 2010 and Jul, 2012, who were initially diagnosed as suspected ATB (active TB). The patients were further categorized into ATB and Not ATB based on clinical and cultural evidences. The performance of TST and T-SPOT.TB were analyzed and compared.

Results: The sensitivity and specificity of T-SPOT.TB were 41.3% and 94.6%, respectively, both higher than TST (12.9% and 91.8%). By combining T-SPOT.TB and TST, the sensitivity did not increase, but specificity was elevated to 100%. TST, T-SPOT.TB and their combinations all performed better in patients with extra-pulmonary diseases than with pulmonary disorders. False-positive T-SPOT.TB results were found to be associated with history of prior TB. In addition, concomitant bacterial infections and low CD4 counts were associated with increased ATB risk.

Conclusions: T-SPOT.TB is superior in screening ATB in HIV-infected patients in China over traditional TST. Additional TST would help to confirm a positive T-SPOT.TB result. Both tests work better for patients with extra-pulmonary conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Female
  • Follow-Up Studies
  • HIV / immunology*
  • HIV / pathogenicity
  • HIV Infections / complications*
  • HIV Infections / immunology
  • HIV Infections / microbiology
  • Humans
  • Interferon-gamma / metabolism*
  • Interferon-gamma Release Tests / standards*
  • Male
  • Mycobacterium tuberculosis / pathogenicity
  • Prospective Studies
  • Risk Factors
  • Tuberculin Test / standards*
  • Tuberculosis / diagnosis*
  • Tuberculosis / etiology

Substances

  • Interferon-gamma

Grants and funding

This work was supported by You’an AIDS and Liver Disease Research Project [BJYAH-2011-019], Capital Medical University Key Laboratory Open Project [2012AZYJ02], Capital Medical University Science Development Grant [2009-1057], Project of Beijing Municipal Science and Technology Commission [D09050703590901], and Beijing Key Laboratory [BZ0089]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.