Evaluation of the Prognostic Value of IFN-[gamma] Release Assay and Tuberculin Skin Test in Household Contacts of Infectious Tuberculosis Cases in Senegal

• Published in: PloS one 2010-05, Vol.5 (5), p.e10508
• Main Authors: Lienhardt, Christian, Fielding, Katherine, Hane, Abdoul A, Niang, Aliou, Ndao, Cheikh T, Karam, Farba, Fletcher, Helen, Mbow, Fatou, Gomis, Jules-François, Diadhiou, Roger, Toupane, Maxime, Dieye, Tandakha, Mboup, Souleymane
• Format: Article
• Language: English
• Subjects: Biological response modifiers; Interferon; Medical research; Medical tests; Skin; Tuberculin; Tuberculosis
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0010508

Chemoprophylaxis of contacts of infectious tuberculosis (TB) cases is recommended for TB control, particularly in endemic countries, but is hampered by the difficulty to diagnose latent TB infection (LTBI), classically assessed through response to the Tuberculin Skin Test (TST). Interferon-gamma release assays (IGRA) are proposed new tools to diagnose LTBI, but there are limited data on their ability to predict the development of active TB disease. To address this, we investigated the response to TST and IGRA in household contacts of infectious TB cases in a TB high-burden country and the potential correlation with development of TB. TST and IGRAs are markers of a contact of the immune system with tubercle bacilli. In a TB endemic area, a high ELISPOT response may reflect increased bacterial replication that may subsequently be associated with development of TB disease and may have a prognostic value. Further longitudinal data are needed to assess whether IGRAs are reliable markers to be used for targeting chemoprophylaxis.