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HelpTest Code SAFB Acid-Fast Smear for Mycobacterium, Varies
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
VariesOrdering 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.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Body fluid
Container/Tube: Sterile container
Specimen Volume: 1 mL
Specimen Type: Bone marrow
Container/Tube: SPS/Isolator System or green top (lithium 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: 4 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: Stool
Supplies: Stool Collection Kit, Random (T635)
Container/Tube: Sterile container
Specimen Volume: 5-10 g
Specimen Type: Tissue
Container/Tube: Sterile container
Specimen Volume: 5-10 mm
Collection Instructions: Collect a fresh tissue specimen.
Specimen Type: Urine
Container/Tube: Sterile container
Specimen Volume: 2 mL
Collection Instructions: Collect a random urine specimen.
Specimen Type: Swab
Additional Information: Fresh tissue or body fluid is the preferred specimen type instead of a swab specimen. Recovery of mycobacteria and aerobic actinomycetes from swabs is variable.
Sources: Wound, tissue, or body fluid
Container/Tube: Culture transport swab (noncharcoal) Culturette
Specimen Volume: Adequate specimen
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.
Specimen will be rejected due to:
Blood or fixed tissue; specimen in viral transport medium (including but not limited to M4, M5, BD viral transport media, thioglycolate broth); swab sources of nasal, sinus, ear, mouth, throat, or scalp; wood shaft or charcoal swab.
Specimen Minimum Volume
Body fluid: 0.5 mL
Respiratory specimen: 3 mL
Fresh tissue: pea-sized piece
If a mycobacterial culture is also requested:
Body fluid: 1.5 mL
Respiratory specimen: 3 mL
Fresh tissue: pea-sized piece
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Refrigerated (preferred) | 7 days | |
| Ambient | 7 days |
Reference Values
Negative (reported as positive or negative)
Day(s) Performed
Monday through Sunday
CPT Code Information
87206
87176-Tissue processing (if appropriate)
87015-Mycobacteria culture, concentration (if appropriate)
Report Available
1 daySpecimen Retention Time
3-7 daysReject Due To
| Blood or serum Prepared slide, glass slide, microscope slide |
 Reject |
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| TBT | Concentration, Mycobacteria | No, (Bill Only) | No |
| TISSR | Tissue Processing | No, (Bill Only) | No |