Interferon-Gamma Release Assay

An interferon-γ release assay (IGRA) is a medical test used in the diagnosis of some infectious diseases, especially tuberculosis. Interferon-γ (IFN-γ) release assays rely on the fact that T-lymphocytes will release IFN-γ when exposed to specific antigens. These tests are mostly developed for the field of tuberculosis diagnosis, but in theory, may be used in the diagnosis of other diseases that rely on cell-mediated immunity, e.g. cytomegalovirus and leishmaniasis and COVID-19. For example, in patients with cutaneous adverse drug reactions, the challenge of peripheral blood lymphocytes with the drug causing the reaction produced a positive test result for half of the drugs tested.