Test Id : TB2LN
Susceptibility, Mycobacterium tuberculosis Complex, Second Line, Varies
Useful For
Suggests clinical disorders or settings where the test may be helpful
Determination of Mycobacterium tuberculosis complex minimal inhibitory concentrations to second-line antimicrobial agents
Additional Tests
Lists tests that are always performed, at an additional charge, with the initial tests.
| Test Id | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| STV2 | Susceptibility, Mtb Cx, 2nd Line | No, (Bill Only) | Yes |
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the additional test will always be performed at an additional charge.
Method Name
A short description of the method used to perform the test
Minimum Inhibitory Concentration (MIC) by Microtiter Broth Dilution Method
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
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)
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the additional test will always be performed at an additional charge.
Specimen Type
Describes the specimen type validated for testing
Varies
Additional Testing Requirements
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.
Shipping Instructions
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.
Necessary Information
Specimen source and suspected organism identification are required.
ORDER QUESTIONS AND ANSWERS
| Question ID | Description | Answers |
|---|---|---|
| Q00M0073 | Specimen source (Required) and Organism Identification (Required unless concurrent identification test is ordered) |
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
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.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
See Specimen Required
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Agar plate | Reject |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Ambient (preferred) | ||
| Refrigerated | |||
Useful For
Suggests clinical disorders or settings where the test may be helpful
Determination of Mycobacterium tuberculosis complex minimal inhibitory concentrations to second-line antimicrobial agents
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the additional test will always be performed at an additional charge.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
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.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Interpretive criteria and reporting guidelines are followed using the Clinical Laboratory Standards Institute (CLSI) M24S document.
Interpretation
Provides information to assist in interpretation of the test results
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.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
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.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
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
Method Description
Describes how the test is performed and provides a method-specific reference
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)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Sunday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
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.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
87186-Susceptibility, Mtb Cx, 2nd Line
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| 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 |