Test Id : CTB
Mycobacteria and Nocardia Culture, Varies
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detection and identification of Mycobacterium species, Nocardia species, and other aerobic actinomycetes
Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.
| Test Id | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| ISMY | ID by 16S Sequencing | No, (Bill Only) | No |
| RMALM | Id MALDI-TOF Mass Spec AFB | No, (Bill Only) | No |
| RTBSP | Id, Mtb Speciation, PCR | No, (Bill Only) | No |
| TBT | Concentration, Mycobacteria | No, (Bill Only) | No |
| TISSR | Tissue Processing | No, (Bill Only) | No |
| LCTB | Id, MTB complex Rapid PCR | No, (Bill Only) | No |
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, a reflex test may be performed at an additional charge.
The following algorithms are available:
-Mycobacterium and Nocardia Culture Algorithm
-Meningitis/Encephalitis Panel Algorithm
Method Name
A short description of the method used to perform the test
Automated Detection of Positive Cultures followed by Organism Identification /DNA Sequencing/Matrix Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry
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) Smear
Acid Fast Smear
Bacillus, acid-fast
Culture for TB (Tuberculosis)
Mycobacteria
Nocardia
Smear, Acid Fast Bacilli-AFB
5180-CTB
TB (Tuberculosis) Culture
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, a reflex test may be performed at an additional charge.
The following algorithms are available:
-Mycobacterium and Nocardia Culture Algorithm
-Meningitis/Encephalitis Panel Algorithm
Specimen Type
Describes the specimen type validated for testing
Varies
Necessary Information
1. Specimen source is required.
2. Alert the laboratory if Mycobacterium genavense is suspected, as this species requires addition of mycobactin J to the culture medium for optimal growth and recovery.
ORDER QUESTIONS AND ANSWERS
| Question ID | Description | Answers |
|---|---|---|
| Q00M0014 | Specimen Source |
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Submit only 1 of the following specimens:
Specimen Type: Body fluid
Container/Tube: Sterile container
Specimen Volume: 1.5 mL
Specimen Type: Bone marrow
Container/Tube: Sterile container, or green top (lithium or sodium heparin)
Specimen Volume: Entire collection
Specimen Type: Gastric washing
Container/Tube: Sterile container
Specimen Volume: 10 mL
Collection Instructions: Neutralize specimen within 4 hours of collection with 100 mg of sodium carbonate per 5 to 10 mL of gastric wash.
Specimen Type: Respiratory
Sources: Bronchoalveolar lavage fluid, bronchial washing, sputum
Container/Tube: Sterile container
Specimen Volume: 3 mL
Collection Instructions:
1. Collect 3 respiratory specimens for acid-fast smears and culture in patients with clinical and chest X-ray findings compatible with tuberculosis.
2. These 3 specimens should be collected at 8 to 24-hour intervals (24 hours when possible) and should include at least 1 first-morning specimen.
Specimen Type: Stool
Supplies: Stool Collection Kit, Random (T635)
Container/Tube: Sterile container
Specimen Volume: 5 to 10 g
Specimen Type: Tissue
Container/Tube: Sterile container
Specimen Volume: 5 to 10 mm
Collection Instructions: Collect a fresh tissue specimen.
Specimen Type: Urine
Container/Tube: Sterile container
Specimen Volume: 20 to 50 mL
Collection Instructions: Collect a random urine specimen.
Fresh tissue or body fluid are preferred over a swab specimen. Recovery of mycobacteria from swabs is generally very low yield. Only submit a swab specimen if tissue biopsy or fluid aspiration is not possible.
Specimen Type: Swab
Supplies: BD E-swab (T853)
Sources: Surgically collected wound, tissue, or body fluid
Container/Tube: Sterile, screw-capped tube containing Liquid Amies Medium with flocked swab (eg, E-swab)
Specimen Volume: Flocked swab in 1 mL of Liquid Amies Medium
Collection Instructions:
1. Before collecting specimen, wipe away any excessive amount of secretion and discharge, if appropriate.
2. Obtain secretions or fluid from source with sterile flocked swab. Paranasal sinus collections must use a nasopharyngeal flocked swab.
3. Place flocked swab in sterile, screw-capped tube containing 1 mL of Liquid Amies Medium.
4. If smear and culture are requested or both a bacterial culture and mycobacterial culture are requested, collect a second swab to maximize test sensitivity. Submit each swab in a separate sterile, screw-capped tube with 1 mL of Liquid Amies Medium.
Additional Information: Swabs from the following sources are not acceptable: respiratory fluid (eg, sputum), nasal, sinus, outer ear, mouth, throat, or scalp. Surgically collected inner ear swabs are acceptable.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send 1 of the following:
-Microbiology Test Request (T244)
-General Request (T239)
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
| Blood, Serum or fixed tissue Environmental sources Specimen in viral transport medium (including but not limited to M4, M5, BD viral transport media, thioglycolate broth) Saliva Swab sources of respiratory fluids (eg, sputum) Swab sources of nasal, sinus, outer ear, mouth, throat, or scalp Wood shaft or charcoal swab Petri dish Boric acid tubes Culture transport swab (eg, Culturette) | 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 | Refrigerated (preferred) | 7 days | |
| Ambient | 7 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detection and identification of Mycobacterium species, Nocardia species, and other aerobic actinomycetes
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, a reflex test may be performed at an additional charge.
The following algorithms are available:
-Mycobacterium and Nocardia Culture Algorithm
-Meningitis/Encephalitis Panel Algorithm
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Mycobacteria species are responsible for significant morbidity and mortality in both immunocompromised and immunocompetent hosts. Mycobacterium tuberculosis is the causative agent of tuberculosis, and it kills nearly 2 million people in the world each year. Nontuberculous mycobacteria such as Mycobacterium avium complex and Mycobacterium abscessus cause a variety of infections (eg, respiratory, skin, and soft tissue) and are important to detect and correctly identify in order to aid in clinical decision making. There are approximately 200 recognized species of mycobacteria and identification of these organisms to the species level is often required to help guide appropriate therapy. Although there are direct detection methods available for M tuberculosis, growth of the organism on culture media is still necessary to allow for antimicrobial susceptibility testing. At this time, direct molecular detection methods are lacking for the nontuberculous mycobacteria and growth in culture is critical for identification and antimicrobial susceptibility testing.
Nocardia species and other aerobic actinomycetes (eg, Tsukamurella species, Gordonia species, Rhodococcus species) are also important causes of disease and isolation on culture media is important to facilitate identification and antimicrobial susceptibility testing. Nocardia and the other aerobic actinomycetes grow well on mycobacterial medium, and therefore, ordering a mycobacterial culture is recommended when infection with this group of organisms is suspected.
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.
Negative
Interpretation
Provides information to assist in interpretation of the test results
A final negative report is issued after 42 days of incubation.
Positive cultures are reported as soon as detected.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Recovery of mycobacteria is dependent on the number of organisms present in the specimen, specimen collection methods, methods of processing, and patient factors such as the use of anti-mycobacteria therapy.
The use of BBL MGIT PANTA antibiotic mixture, although necessary for all nonsterile specimens, may have inhibitory effects on some mycobacteria.
Supportive Data
The Bactec 460 and Bactec MGIT 960 systems were compared. A total of 1963 patient specimens were cultured, including 1519 respiratory tract specimens that required decontamination with sodium hydroxide and 444 sterile specimens that did not need to be decontaminated. A total of 168 cultures grew acid-fast bacilli in 1 or both systems (8.5% positivity rate). The contamination rate for positive respiratory tract specimens was 3.8% in the Bactec 460 and 7.9% in the MGIT. Contamination of sterile specimens was 6.3% in the Bactec 460 and 10.1% in the MGIT. Combined rates were 4.3% for the Bactec 460 and 8.4% for the MGIT. The overall recovery rates for mycobacterial species, excluding Mycobacterium gordonae, were 82.8%, 79.1%, and 78.4% for the Bactec 460, MGIT 960, and solid media, respectively. Recovery rates for the Bactec 460 and MGIT 960 were considered to be equivalent.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Martin I, Pfyffer GE, Parrish N: Mycobacterium: General characteristics, laboratory detection and staining procedures. In: Carroll KC, Pfaller MA, Landry ML, et al, eds. Manual of Clinical Microbiology. 12th ed. Vol 1. ASM Press;2011:472-5022.
2.Banaei N, Musser KA, Salfinger M, Somoskovi A, Zelazny AM. Novel assays/applications for patients suspected of mycobacterial diseases. Clin Lab Med. 2020;40(4):535-552. doi:10.1016/j.cll.2020.08.010
3. Lafont E, Conan PL, Rodriguez-Nava V, Lebeaux D. Invasive nocardiosis: Disease presentation, diagnosis and treatment - old questions, new answers? Infect Drug Resist. 2020;13:4601-4613. doi:10.2147/IDR.S249761
Method Description
Describes how the test is performed and provides a method-specific reference
The BACTEC MGIT 960 System is a broth system designed for the rapid detection of mycobacteria in clinical specimens. Mycobacteria Growth Indicator Tubes (MGIT) are incubated for up to 42 days and growth is evaluated with mycobacteria identified as soon as a MGIT signals positive on the instrument.
In addition to the MGIT tube, Middlebrook 7H10/7H10S agar biplates are inoculated and incubated at 37 degrees C for 42 days. Growth from positive MGITs or agar plates is identified using a variety of techniques as appropriate including rapid polymerase chain reaction, matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, or 500 basepair 16S rRNA gene sequencing.
The Mycobacterium tuberculosis complex will be identified to the species level upon request using rapid polymerase chain reaction.(Martin I, Pfyffer GE, Parrish N: Mycobacterium: General characteristics, laboratory detection and staining procedures. In: Carroll KC, Pfaller MA, Landry ML, et al, eds. Manual of Clinical Microbiology. 12th ed. Vol 1. ASM Press; 2019:558-575; Halse TA, Escuyer VE, Musser KA: Evaluation of a single tube multiplex real-time PCR for differentiation of the Mycobacterium tuberculosis complex in clinical specimens. J Clin Microbiol. 2011;49[7]:2562-2567. doi:10.1128/JCM.00467-11)
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 has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
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.
87116-Mycobacterial Culture
87015-Mycobacteria Culture, Concentration (if appropriate)
87118-Id MALDI-TOF Mass Spec AFB (if appropriate)
87150-Id, Mtb Speciation, PCR (if appropriate)
87153-Mycobacteria Identification by Sequencing (if appropriate)
87176-Tissue Processing (if appropriate)
87150- Id, MTB complex Rapid PCR (if appropriate)
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 |
|---|---|---|
| CTB | Mycobacterial Culture | 543-9 |
| 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.
|
|---|---|---|
| CTB | Mycobacterial Culture | 543-9 |