A 4-protein signature was identified, comprising bFGF, GCSF, IFNγ, and IL1RA (Table 3A) that differentiated Household contacts with Mtb infection from QFT consistent negatives with an AUC of 0.81 (95% CI, 0.72–0.90; Figure 5B), sensitivity of 87.0% (95% CI, 75.1–94.6), and specificity of 62.5% (95% CI, 43.7–78.9; Table 3B) for safe assignment to no TB treatment. Here, FGF2 is linked to tuberculosis.