Evaluation of Mycobacterium tuberculosis-specific IFN-γ, TNF-α, CXCL10, IL2, CCL2, CCL7 and CCL4 levels for active tuberculosis diagnosis

Our study evaluates seven previously reported biomarkers for active tuberculosis (ATB) diagnosis. We compared Mycobacterium tuberculosis -specific IFN-γ, TNF-α, CXCL10, IL2, CCL2, CCL7 and CCL4 levels in patients with ATB and non-tuberculosis respiratory diseases. Our ATB group included equal numbers of patients with positive and negative QuantiFERON-TB Gold In-Tube (QFT-GIT) results, to assess whether any biomarker offered superior diagnostic accuracy to IFN-γ. No biomarker achieved higher sensitivity than QFT-GIT for ATB diagnosis without significant loss of specificity. Our study design provides an efficient strategy for rapidly gating future biomarkers by using clinically relevant and representative patient groups in whom current QFT-GIT tests fail.