IFNG and sarcoidosis: Clinical diagnostic validation using the GSE83456 dataset further highlighted CD39’s utility, yielding an AUC of 0.7270 (95% CI: 0.6214-0.8365, p = 0.0002) for distinguishing PTB from sarcoidosis, compared to IFN-γ’s lower accuracy (AUC = 0.6286) (Figure 3C).