Thomason JL, Obih UM, Koelle DM, et al. - Researchers tried to find out the diagnostic correlations of elevated spontaneous IFN-γ release (SIR) and the potential use of IFN-γ release assay (IGRA)-nil control (NL) as a novel biomarker in SLE. Diagnostic code frequencies were examined among 11,823 individuals undergoing mycobacterium tuberculosis (TB)-IGRA testing between 2010 and 2015 in a large urban US health-care system. To study the correlation between IGRA-NL and SLE, they distinguished 99 individuals with SLE and TB-IGRA test results then evaluated associations between IGRA-NL, normalized IGRA-NL (the quotient of IGRA-NL/IGRA-mitogen), disease manifestations and disease activity. Increased SIR seems to be correlated with a limited number of disease processes, including SLE. The diagnostic utility of SIR remains to be ascertained. The data showed that in patients with SLE, IFN-γ activation, as tested by the TB-IGRA test, may offer a readily available tool for evaluating disease activity.