Test Catalog

Test Id : SAFB

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Acid-Fast Smear for Mycobacterium, Varies

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Overview

Test Catalog

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of acid-fast bacilli in clinical samples

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
TBT Concentration, Mycobacteria No, (Bill Only) No
TISSR Tissue Processing 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, the reflex tests may be performed at an additional charge.

 

For more information see Meningitis/Encephalitis Panel Algorithm

Method Name
A short description of the method used to perform the test

Auramine-Rhodamine Stain

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Acid Fast Smear For Mycobacterium

Aliases
Lists additional common names for a test, as an aid in searching

Acid-Fast Bacilli (AFB)

Acid-Fast Smear for Mycobacterium

AFB (Acid-Fast Bacilli)

Bacillus, Acid-Fast

MTB (Mycobacterium tuberculosis)

Mycobacterium tuberculosis (MTB)

Smear, Acid-Fast Bacilli (AFB)

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 reflex tests may be performed at an additional charge.

 

For more information see Meningitis/Encephalitis Panel Algorithm

Specimen Type
Describes the specimen type validated for testing

Varies

Ordering Guidance

For the preferred test for rapid, direct detection of Mycobacterium tuberculosis from clinical specimens, order MTBRP / Mycobacterium tuberculosis Complex, Molecular Detection, PCR, Varies.

Necessary Information

Specimen source is required.

ORDER QUESTIONS AND ANSWERS

Question ID Description Answers
Q00M0050 Specimen Source

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Fresh tissue or body fluid are the preferred specimen types. Recovery of mycobacteria from swabs is generally very low yield.

 

Submit only 1 of the following specimens:

 

Preferred:

 

Specimen Type: Body fluid

Container/Tube: Sterile container

Specimen Volume: 1 mL

Collection Information: Saliva is not acceptable.

Additional Information: If a mycobacterial culture is also requested, collect 1.5 mL.

 

Specimen Type: Bone marrow

Container/Tube: Sterile container or green top (lithium heparin)

Specimen Volume: Entire collection

Collection Instructions:

1. Invert several times to mix bone marrow.

2. Send bone marrow specimen in original tube. Do not aliquot.

 

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:  mL

Collection Instructions: Collect 3 respiratory specimens for acid-fast smears and culture in patients with clinical and chest X-ray findings compatible with tuberculosis. 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: Feces

Supplies: Stool Collection Kit, Random (T635)

Container/Tube: Sterile container

Specimen Volume: 5 to10 g

 

Specimen Type: Tissue

Container/Tube: Sterile container

Specimen Volume: 5 to10 mm

Collection Instructions: Collect a fresh, unfixed tissue specimen. Fixed tissue is not acceptable.

 

Specimen Type: Urine

Container/Tube: Sterile container

Specimen Volume: 2 mL

Collection Instructions: Collect a random urine specimen.

 

Acceptable:

 

Specimen Type: Swab

Sources: Wound, tissue, or body fluid

Container/Tube:

Preferred: Flocked swab (eg, Eswab)

Acceptable: Culture transport swab, noncharcoal (eg, Culturette)

Specimen Volume: Swab

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 swab.

3. If smear and culture are requested or both a bacterial culture and mycobacterial culture are requested, collect a second swab to maximize test sensitivity.

4. Swabs from the following sources are not acceptable: respiratory fluid (eg, sputum), nasal, sinus, ear, mouth, throat, or scalp.

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 forms with the specimen:

-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

Specimen in viral transport medium (including but not limited to M4, M5, BD viral transport media, thioglycolate broth)
Wood shaft, charcoal or gel swab
Prepared slide, glass slide, microscope slide 		 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 7 days
Refrigerated (preferred) 7 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Detection of acid-fast bacilli in clinical samples

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

When this test is ordered, the reflex tests may be performed at an additional charge.

 

For more information see Meningitis/Encephalitis Panel Algorithm

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Mycobacterium tuberculosis is a leading infectious disease cause of death worldwide. The Centers for Disease Control and Prevention has reported a rise in the incidence of tuberculosis associated with AIDS, foreign-born cases, and increased transmission in high-risk populations. There has also been a rise in the number of M tuberculosis strains that exhibit resistance to one or more antituberculosis drugs. The public health implications of these facts are considerable. Because M tuberculosis is readily spread by airborne particles, rapid diagnosis and isolation of infected persons is important. Nontuberculous mycobacteria infections also cause significant morbidity and mortality in humans, particularly in immunocompromised persons. Detection of acid-fast bacilli in sputum and other specimens allows rapid identification of individuals who are likely to be infected with mycobacteria while definitive diagnosis and treatment are pursued.

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 (reported as positive or negative)

Interpretation
Provides information to assist in interpretation of the test results

Patients whose sputum samples are identified as acid-fast positive should be considered potentially infected with Mycobacterium tuberculosis, pending definitive diagnosis by molecular methods or mycobacterial culture.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Artifacts may exhibit nonspecific fluorescence and be confused with organisms.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Daley CL, Iaccarino JM, Lange C, et al. Treatment of nontuberculous mycobacterial pulmonary disease: An official ATS/ERS/ESCMID/IDSA clinical practice guideline [published correction appears in Clin Infect Dis. 2020 Dec 31;71(11):3023. doi:10.1093/cid/ciaa1062]. Clin Infect Dis. 2020;71(4):e1-e36. doi:10.1093/cid/ciaa241

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. doi:10.1164/rccm.v201erratum2]. Am J Respir Crit Care Med. 2019;200(10):e93-e142. doi:10.1164/rccm.201909-1874ST

Method Description
Describes how the test is performed and provides a method-specific reference

Auramine-rhodamine fluorochrome stain prepared and read with fluorescent microscope.(Martin I, Pfyffer GE, Parrish N: Mycobacterium: General Characteristics, Laboratory Processing, Staining, Isolation and Detection Procedures. In: Carroll KC, Pfaller MA, Pritt BS, et al. Manual of Clinical Microbiology. 13th ed. ASM Press; 2023)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

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.

1 day

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

3 to 7 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

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.

87206

87176-Tissue processing (if appropriate)

87015-Mycobacteria culture, concentration (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
SAFB Acid Fast Smear For Mycobacterium 676-7
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.
SAFB Acid Fast Smear For Mycobacterium 676-7

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
Test Changes - Specimen Information 2025-07-01