Consenting adults presenting with signs and symptoms compatible with pulmonary tuberculosis will be interviewed for demographic and medical information, and then will be asked to provide 3-4 expectorated sputum specimens. In the study laboratory, sputa will be tested using conventional and investigational diagnostic tests for tuberculosis and rifampin resistance.

Inclusion Criteria:

Case Detection Group:

• Age 18 years or above
• Clinical suspicion of pulmonary TB (including cough ≥2 week and at least 1 other symptom typical of TB);
• Willingness to provide 3-4 sputum specimens at enrolment;
• Willingness to have a trial follow-up visit approximately 2 months after enrolment;
• Provision of informed consent.

Drug Resistant TB Group:

In addition to the criteria of the Case Detection Group, participants should also meet the following conditions:

• Non-converting pulmonary TB cases (category I and category II failures)

Exclusion Criteria:

Case Detection Group:

• Receipt of any dose of TB treatment within 60 days prior to enrolment (even if within last two days only).

Drug Resistant TB Group:

• Receipt of any dose of MDR-TB treatment within 60 days prior to enrolment (even if within last two days only).

Patients will be recruited from outpatient TB clinics at district or regional health facilities. Given the important role of the private sector in India, 1 private laboratory will be included in the trial which is an MDR reference hospital.

This is a multi-centre trial conducted in four countries: India, Peru, Papua New Guinea and Ethiopia. Countries were selected to be globally representative of the TB epidemic.