Abstract: Objective Diagnosis of osteoarticular tuberculosis (TB) remains a challenge for clinician. The aim of the present study was to evaluate the utility of T-SPOT.TB assay and tuberculosis antibody for diagnosing osteoarticular tuberculosis.  Methods  From July 2011 to October 2013, 92 patients with confirmed osteoarticular TB and 64 patients without active osteoarticular TB were enrolled. All patients came from Department of Orthopedics，Beijing Chest Hospital.All patients underwent T-SPOT.TB assay to measure the interferon gamma (IFN-γ) response to the TB-specific antigens early secretory antigenic target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10) in T cells in samples of peripheral blood mononuclear cells（PBMCs）, meanwhile serum tuberculosis antibody was detected using western blot method.  Results The sensitivity and specificity for T-SPOT.TB assay were 93.5%（86/92） and 78.1%（50/64）, for tuberculosis antibody were 64.1%（59/92） and 81.3%（52/64）, respectively. The positive rate of T-SPOT.TB assay was significantly higher than tuberculosis antibody method, and the difference was statistically significant (χ²=23.72，P<0.01).  Conclusion The data on this subject suggested that the T-SPOT.TB assay is a useful adjunctive tool for the diagnosis of osteoarticular TB.

Key words: Tuberculosis, osteoarticular/diagnosis, Interferon-gamma release tests, Antibodies, bacterial