Updated Guidelines for Using Interferon Gamma Release Assays to Detect Mycobacterium tuberculosis Infection – United States, 2010

This serial presents updated guidelines to US public health officials, healthcare providers, and laboratory workers for use of FDA-approved interferon gamma release assays (IGRAs) to diagnose both active and latent TB infection in adults and children. These guidelines include use of the QuantiFERON-TB Gold In-Tube Test (QFT-GIT) and the T-SPOT.TB Test (T-Spot), two new IGRAs that were not included in the previous guidelines published in 2005. The antigens, methods, and interpretation criteria for these assays differ from those for IGRAs approved previously. Although there has been progress in documenting the utility of IGRAs, further studies and research are needed. Specific areas needing additional research are listed.