Order when phenotypic drug susceptibility testing is required for M. tuberculosis treatment. For genotypic (DNA sequencing) resistance testing, refer to Mycobacterium tuberculosis Drug Resistance by Sequencing (2011713).
- Patient Preparation
- Actively growing isolate of Mycobacterium tuberculosis in pure culture.
- Specimen Preparation
- Transport sealed container with pure culture on solid or liquid media. Place each specimen in an individually sealed bag.
- Storage/Transport Temperature
- Room temperature.
Submit specimen according to Infectious Substance, Category A, shipping guidelines.
- Unacceptable Conditions
- Mixed cultures or non-viable organisms. Organisms submitted on agar plate.
- Ambient: 2 weeks; Refrigerated: 2 weeks; Frozen: Unacceptable
Drugs tested: Ethambutol: 5.0 µg/mL,isoniazid: 0.1 µg/mL (0.4 µg/mL if resistant to 0.1 µg/mL), pyrazinamide: 100 µg/mL,and rifampin: 1.0 µg/mL.
This procedure screens isolates of M. tuberculosis complex for drug resistance. The procedure does not use serial dilutions to provide quantitative MIC values. Single critical concentrations for each antimycobacterial agent used have been defined by the United States Public Health Service.
|Component Test Code*||Component Chart Name||LOINC|
|0060347||Susceptibility, M. tuberculosis Primary|
- AFB primary panel
- Ethambutol susceptibility
- isoniazid susceptibility
- pyrazinamide susceptibility
- rifampin susceptibility