TB Gold plus is a test for latent tuberculosis and an aid for diagnosing M. tuberculosis complex infection in sick patients. A positive TB Gold plus result should not be the sole or definitive basis for determining infection with M. tuberculosis. A positive TB Gold plus result should be followed by further medical evaluation and diagnostic evaluation for active tuberculosis disease ( eg AFB smear and culture , Chest X-ray). A negative TB Gold plus result does not preclude the possibility of M. tuberculosis infection or tuberculosis disease. The magnitude of the measured IFN-gamma level cannot be correlated to stage or degree of infection, level of immune responsiveness likelihood for progression to active disease or it cant differentiate between latent infection and active tuberculosis. A positive TB Gold plus result may be due to infection by M.kansasii, M. szulgai or M. marinum. If such infections are suspected, alternative tests should be investigated.