Diagnosis of active and latent pulmonary tuberculosis, as well as extrapulmonary tuberculosis, is still a major challenge of TB control in China. This observational study aims to evaluate TB-antigen responsive T cell markers in the diagnosis of tuberculosis and extrapulmonary tuberculosis and try to find new prompt and cost-effective laboratory tests for active TB screening.

The enrolled patients will be grouped into active or latent tuberculosis according to the bacteriological evidence of TB. The TB-antigen responsive T cell markers will be examined. The performance of each T cell marker for the diagnosis of active TB will be systematically evaluated.

Inclusion Criteria:

• any patients suspicious of TB infection
• TB culture and Xpert test required
• Chest X-ray required

Exclusion Criteria:

• anti-TB therapy before the sample collection.

Any patients suspicious of TB infection

The sharing of individual participant data will be decided by the sponsor after the accomplishment of the study.