Predictive value of interferon-gamma release assays and tuberculin skin testing for predicting progression from latent TB infection to disease state: a meta-analysis.
Chest. 2012 Apr 5;
Authors: Diel R, Loddenkemper R, Nienhaus A
Abstract
AbstractBackgroundGiven the present lack of effective vaccines against tuberculosis (TB), the accuracy of screening tests for determining or excluding latent TB infection (LTBI) is decisive in effective TB control. This meta-analysis critically appraises studies investigating the positive and the negative predictive value (PPV and NPV) from a test-determined LTBI state for progression to active TB of interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST).MethodsWe searched Medline, EMBASE and Cochrane bibliographies for relevant articles. After qualitative evaluation, the PPV and NPV for progression of commercial and "in-house" IGRAs and the TST for persons not receiving preventive treatment (PT) in the context of the respective IGRA studies were pooled using both a fixed and a random effect model. Weighted rates were calculated for all study populations and for groups at high risk of TB development solely.ResultsThe pooled PPV for progression for all studies using commercial IGRAs was 2.7% [95%CI 2.3-3.2] compared with 1.5% [95%CI 1.2-1.7] for the TST [p<0.0001]. PPV increased to 6.8% [95%CI 5.6-8.3] and 2.4% [95%CI 1.9-2.9] for the IGRAs and the TST respectively when only high-risk groups were considered [p<0.0001].Pooled values of NPV for progression for both IGRAs and the TST were very high at 99.7% [95%CI 99.5-99.8] and 99.4% [95%CI 99.2-99.5], although significantly higher for IGRAs [p<0.01].ConclusionsCommercial IGRAs have a higher PPV and NPV for progression to active TB compared to those of the TST, especially when performed in high-risk persons.
PMID: 22490872 [PubMed - as supplied by publisher]