Susceptibility, Mycobacterium tuberculosis Complex, Second Line, Varies
Use
This test is useful for determining the minimal inhibitory concentrations (MIC) of Mycobacterium tuberculosis complex against second-line antimicrobial agents. It is commonly applied when the organism is resistant to first-line drugs such as rifampin and isoniazid, or when the physician intends to include a fluoroquinolone in the therapy. Testing includes agents such as amikacin, ethionamide, kanamycin, moxifloxacin, ofloxacin, p-aminosalicylic acid, rifabutin, and streptomycin. Results guide clinical decisions for patients with drug-resistant tuberculosis.
Special Instructions
Specimen source and suspected organism identification are required. When organism identification is not provided, additional culture tests may be necessary. Ensure that the organism is in pure culture and actively growing for accurate susceptibility testing.
Limitations
The test employs Clinical and Laboratory Standards Institute (CLSI) guidelines for the interpretation of susceptibility results. However, results for certain antimycobacterial agents may have tentative breakpoints established by Mayo Clinic for those lacking consensus guidelines. Ethambutol, isoniazid, and rifampin are not routinely reported with this test.
New York Approved
Methodology
Culture-based
Biomarkers
LOINC Codes
- 29579-0
- 29579-0
Result Turnaround Time
21-30 days
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
Isolate
Minimum Volume
Not provided
Container
Middlebrook 7H10 agar slant
Collection Instructions
Organism must be in pure culture, actively growing.
Causes for Rejection
Agar plate
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Ambient (preferred) |