Research

Evaluation of novel, T-cell based diagnostic tools for TB infection

Detection and treatment of latent TB infection (LTBI) is an important component of TB control. Currently, diagnosis of LTBI relies on the tuberculin skin test (TST), a century-old test with several limitations. A breakthrough in recent years has been the development of interferon-g release assays (IGRAs) for LTBI. From a clinical and public health perspective, it is important to determine if IGRAs should replace the TST, and to assess their role and relevance in high burden countries. By conducting field evaluations of IGRAs in India, we have generated interesting and useful information on how these tests perform in a high burden country, especially in high-risk populations such as healthcare workers, children and TB patients with HIV co-infection. For example, our study in India compared the TST with an IGRA in over 700 healthcare workers - the largest study of its kind (JAMA 2005; 293:2746-55). Our data has informed evidence-based guidelines on how IGRAs should be used in clinical practice. They have also been used by FIND, TDR & WHO to develop a research agenda for the evaluation of these tests in resource-limited settings (Lancet Infect Dis 2007;7;428-38).

Close Window