Differentiation of TB to BCG vaccination and NTMs
In recent years Interferon-γ-Release-Assays (IGRAs) have been established in the diagnosis of acute and latent infection with Mycobacterium tuberculosis. By using antigens, which are not present in BCG-vaccination strain, no cross reactivity occurs at vaccinated persons.
In contrast to ELISA technique the EliSpot method shows a higher specificity and sensitivity.
In addition to the diagnosis of latent TB, the IGRA is applicable to control contact persons / household contact and gives assistance in the diagnosis of acute tuberculosis.