IFNG and tuberculosis: To overcome these shortcomings, numerous biomarkers using mycobacterial and host factors have been evaluated.2,4–6 Although most of the markers do not have high levels of validity, the interferon (IFN)-γ release assay (IGRA) has shown utility for the diagnosis of active TB and latent TB infection, significantly outperforming the classical tuberculin skin test.7,8 However, in terms of treatment monitoring, the IGRA is less useful.