Test Overview
Real-Time Polymerase Chain Reaction (PCR)
Rapid detection of Mycobacterium tuberculosis complex. This test should always be performed in conjunction with mycobacterial culture.
Negative
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
A positive result indicates the presence of Mycobacterium tuberculosis complex DNA. Members of the M tuberculosis complex detected by this assay include M tuberculosis, Mycobacterium bovis, Mycobacterium bovis bacillus Calmette-Guerin, Mycobacterium africanum, Mycobacterium canettii, and Mycobacterium microti. Other species within the M tuberculosis complex (eg, Mycobacterium caprae, Mycobacterium pinnipedii, and Mycobacterium mungi) should, in theory, be detected using the primer and probe sequences in this assay, but they have not been tested. This assay method does not distinguish between the species of the M tuberculosis complex. If an isolate of M tuberculosis complex is already available, species identification can be performed; order TBSP / Mycobacterium tuberculosis Complex Species Identification, PCR, Varies.
A negative result indicates the absence of detectable M tuberculosis complex DNA.
Isoniazid (INH) resistance mediated through a katG variant will be reported when observed but lack of a katG variant does not imply that the isolate is susceptible to INH. There are other genetic loci in addition to katG that can contribute to resistance for this drug.
Test Details
2 - 4 days
- AFB RNA Amplification, Respiratory
- Mycobacteria PCR Test
- TB RNA Amplification, Respiratory
- TB PCR Test
Specimen Requirements
Send respiratory specimen (e.g., bronchoalveolar lavage fluid, bronchial washing, or sputum) or 5 mm fresh tissue specimen refrigerated in a screw-capped, sterile container. Formalin-fixed paraffin-embedded tissue is also acceptable. Indicate specimen source and collection date/time.
Specimen must arrive within 7 days of collection or specimen will be rejected
Additional Information
This test is specific for, but does not differentiate among, members of the Mycobacterium tuberculosis complex, i.e., Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium bovis BCG, Mycobacterium africanum, Mycobacterium microti, and Mycobacterium canetti. Test sent to Mayo Medical Laboratories.