Clinical application of enzyme-linked immunospot assay for rapid diagnosis of active tuberculosis

Objective To evaluate the clinical application of enzyme-linked immunospot(ELISPOT) assay for detection of M.tuberculosis antigen specific T cells in the rapid diagnosis of active tuberculosis.Methods Using the rapid enzyme-linked immunospot assay for detection of T cells with secretion of IFN-γ specific for M.tuberculosis antigens in blood samples from 112 patients with tuberculosis, 24 patients with hepatitis C, 30 healthy persons, and 65 with other respiratory diseases.Results 107 of 112 tuberculosis patients had detectable M. tuberculosis antigen-specific T cells, whereas 2 of 30 healthy subjects and 65 patients with non-tuberculosis illnesses responded. This assay has a sensitivity of 95.5%, specificity of 93.3%.Conclusions M.tuberculosis specific T cells could serve as accurate markers of M.tuberculosis infection in an area of high tuberculosis prevalence.ELISPOT is a rapid, sensitive and specific method for detecting M.tuberculosis specific T cells.It also gives objective evidence to the diagnosis of active tuberculosis.