New advances in diagnosis of latent tuberculosis infection: A review article

Abstract

Context: It has been estimated that one-third of the world’s population are suffering from latent tuberculosis infection (LTBI). In order to control tuberculosis in high-risk groups proper diagnosis and treatment is essential. Evidence Acquisition: Useless and expensive tests such as unfocused population-based tests can lead to futile and unnecessary treatments. Targeted screening approaches and individualization of LTBI treatment protocols must be a priority. Results: Diagnostic methods with immune based tests such as the tuberculin skin test (TST) or interferon gamma release assays (IGRA) can accurately detect LTBI. However, interferon-gamma release assays have higher specificity than TST in Bacille Camette-Gurin (BCG)-vaccinated populations; both tests are precise to identify latent tuberculosis. However, it is of great concern that both tests have insignificant roles in predicting risk of progression to active tuberculosis. Conclusions: Here we review the clinical applications, advantages, and limitations of the tuberculin skin test and interferon-gamma release assays and provide an overview of the most recent systematic reviews conducted for the comparison of these tests.