Indicator Explainer
MTB DNA
Direct molecular detection of Mycobacterium tuberculosis complex in respiratory specimens.
This page explains what the indicator is and how results are interpreted in general terms. Reference ranges depend on the laboratory, the method, and your own situation — no single “normal value” applies to everyone. This page is health information, not a diagnosis. For symptoms, treatment, or urgent concerns, contact a healthcare professional.
When it is tested
Ordered when tuberculosis is suspected to speed up confirmation versus culture; some platforms also report rifampicin-resistance markers in the same run.
Reading results
A positive molecular result supports TB diagnosis but culture remains the reference for susceptibility beyond the included resistance markers; a negative result does not exclude TB when clinical suspicion is high, because bacillary load and sample quality affect sensitivity.
Questions to ask a professional
- Does this assay include resistance marker reporting?
- What specimen types are validated here?
References
- Oral swabs with a rapid molecular diagnostic test for pulmonary tuberculosis in adults and children: a systematic review. — The Lancet. Global health, 2024 (PMID doi: 10.1016/S2214-109X(23)00469-2)
- Innovo GenMax MTB-RIF/INH: a moderate-complexity automated NAAT for rapid simultaneous detection of Mycobacterium tuberculosis complex and rifampin/isoniazid resistance. — Frontiers in cellular and infection microbiology, 2025 (PMID doi: 10.3389/fcimb.2025.1600170)