Introduction A major challenge in tuberculosis (TB) control is the diagnosis and the treatment of latent tuberculosis infection.
State of art At the present time, the diagnosis is based on tuberculin skin test (TST). TST is not specific, has poor sensitivity and is not easy to perform.
Perspectives Two interferon-based tests for the diagnosis of tuberculosis have just been licensed. These tests have some advantages on TST. They only require a blood sample and their results are not dependent on the examiner. Their specificity is higher than TST because they don’t cross-react with BCG vaccine and with most of the environmental Mycobacterium species. In addition, their sensitivity is higher for the diagnosis of active tuberculosis. In latent tuberculosis, the interferon-gamma assays show better correlation with exposure to Mycobacterium tuberculosis than TST. Both tests seem to show reduced ability to detect TB in immunocompromised patients, in particular the medically immunocompromised.
Conclusions Interferon-gamma assays seems to be useful tools in TB detection, but these good results have to be confirmed with larger studies of non selected patients.
© 2007 Elsevier Masson SAS. Tous droits réservés.