Determination of Mycobacterium tuberculosis complex minimal inhibitory concentrations to second-line antimicrobial agents
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
STV2 | Susceptibility, Mtb Cx, 2nd Line | No, (Bill Only) | Yes |
When this test is ordered, the additional test will always be performed at an additional charge.
Minimum Inhibitory Concentration (MIC) by Microtiter Broth Dilution Method
Acid-Fast Bacilli (AFB)
AFB (Acid-Fast Bacilli)
Antibiotic Susceptibility
Antimicrobial Susceptibility, Mycobacterium tuberculosis
Bacillus, Acid-Fast
MTB (Mycobacterium tuberculosis)
Mycobacteria Antimicrobial Susceptibility (MIC) (Minimum Inhibitory Concentration)
Mycobacterium tuberculosis (MTB)
Susceptibility Testing
Susceptibility, Mycobacterium tuberculosis
TB (Tuberculosis)
Tubercle Bacilli: Mycobacterium tuberculosis
Tuberculosis (TB)
When this test is ordered, the additional test will always be performed at an additional charge.
Varies
If organism identification is not provided, CTB / Mycobacteria and Nocardia Culture, Varies or CTBID / Culture Referred for Identification, Mycobacterium and Nocardia, Varies must also be ordered and will be charged separately.
1. For shipping information see Infectious Specimen Shipping Guidelines.
2. Place specimen in a large infectious container and label as an etiologic agent/infectious substance.
Specimen source and suspected organism identification are required.
Question ID | Description | Answers |
---|---|---|
Q00M0073 | Specimen source (Required) and Organism Identification (Required unless concurrent identification test is ordered) |
Specimen Type: Organism
Supplies: Infectious Container, Large (T146)
Container/Tube: Middlebrook 7H10 agar slant
Specimen Volume: Isolate
Collection Instructions: Organism must be in pure culture, actively growing.
See Specimen Required
Agar plate | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Ambient (preferred) | ||
Refrigerated |
Determination of Mycobacterium tuberculosis complex minimal inhibitory concentrations to second-line antimicrobial agents
When this test is ordered, the additional test will always be performed at an additional charge.
The Clinical and Laboratory Standards Institute (CLSI) provides a consensus protocol for the methods, antimycobacterial agents, and concentrations of each agent to be tested to permit standardized interpretation of Mycobacterium tuberculosis complex susceptibility testing results. CLSI guidelines suggest that additional agents should be tested when an isolate of M tuberculosis complex is resistant to rifampin, is monoresistant to the critical concentration of isoniazid and the physician intends to use a fluoroquinolone for therapy or is resistant to any combination of two first-line agents.
This test uses a broth microdilution minimal inhibitory concentration (MIC) method for susceptibility testing of M tuberculosis complex against antimycobacterial agents. Agents tested are amikacin, ethionamide, kanamycin, moxifloxacin, ofloxacin, p-aminosalicylic acid, rifabutin, and streptomycin.
Interpretive criteria and reporting guidelines are followed using the Clinical Laboratory Standards Institute (CLSI) M24S document.
Results are reported as minimal inhibitory concentrations in mcg/mL.
This test is used as an alternative to TB1LN / Antimicrobial Susceptibility, Mycobacterium tuberculosis Complex, First Line, Varies for ethambutol, isoniazid and rifampin when reagents are not available to perform the TB1LN test. Ethambutol, isoniazid, and rifampin are not routinely reported with this test.
Clinical and Laboratory Standards Institute (CLSI) interpretive criteria are used for agents with established criteria. For all other agents, tentative breakpoints were established by Mayo Clinic by comparison to the critical concentration established by CLSI for each drug and are considered tentative until consensus guidelines are established.
Drug susceptibility testing should be performed on pure culture isolates of Mycobacterium tuberculosis complex.
1. Hall L, Jude KP, Clark SL, et al. Evaluation of the Sensititre MycoTB plate for susceptibility testing of the Mycobacterium tuberculosis complex against first- and second-line agents. J Clin Microbiol. 2012;50:3732-3734
2. Nahid P, Mase SR, Migliori GB, et al. Treatment of Drug-Resistant Tuberculosis. An Official ATS/CDC/ERS/IDSA Clinical Practice Guideline [published correction appears in Am J Respir Crit Care Med. 2020 Feb 15;201(4):500-501
3. Clinical and Laboratory Standards Institute (CLSI). Susceptibility Testing of Mycobacteria, Nocardia spp., and Other Aerobic Actinomycetes. 3rd ed. CLSI standard M24. CLSI; 2018
4. Clinical and Laboratory Standards Institute (CLSI). Performance Standards for Susceptibility Testing of Mycobacteria, Nocardia spp., and Other Aerobic Actinomycetes. 2nd ed. CLSI supplement M24S. CLSI; 2023
This test utilizes the Sensititre MycoTB broth microtiter dilution plate (Trek/ThermoFisher). Antimicrobials are tested according to CLSI M24 guidelines.(Thermo Scientific Sensititre MIC Susceptibility Plates for Mycobacterium tuberculosis. Product Insert. 011-MYCOTB-CID9502. Revision Date: 09/07/2016; Brown-Elliott, BA, Cirillo DM, Musser KA, Rowlinson M-C. Susceptibility Test Methods: Mycobacteria, Nocardia, and Other Actinomycetes. In: Carroll KC, Pfaller MA, eds. Manual of Clinical Microbiology, 13th Edition. ASM Press, 2023)
Monday through Sunday
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
87186-Susceptibility, Mtb Cx, 2nd Line
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
TB2LN | Susceptibility, Mtb Complex, 2 Line | 29579-0 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
TB2LN | Susceptibility, Mtb Complex, 2 Line | 29579-0 |
Change Type | Effective Date |
---|---|
Test Status - Test Resumed | 2024-08-08 |
Test Status - Test Down | 2024-06-17 |
Test Status - Test Delay | 2024-05-31 |
Test Changes - Method | 2022-11-30 |