Test Code MIC1 Acid Fast Culture
Clinical Information
Detection and identification of Mycobacterium species and Nocardia species.
Synonym
- AFBCX
Specimen Required
Preferred Container/Tube: Sterile Container
Acceptable Container/Tube: Sterile Container
Specimen Source: Sterile body fluid, urine (unpreserved), respiratory
Specimen Minimum Volume: Fluids 1 mL, Tissue 5 mm
Specimen Collection Information
Transport refrigerated specimen to laboratory as soon as possible. Do not refrigerate bone marrow or CSF specimens.
Fresh tissue (5-10 mm) or body fluid (1-1.5ml) should be collected. ESwabs are not accepted. A separate tissue or body fluid specimen must be submitted for mycobacterial culture, as it requires distinct handling and processing protocols.
Fine needle aspiration (FNA) yields limited material and may not meet the minimum tissue volume (5–10 mm) required for optimal culture sensitivity. Core needle biopsy is preferred for microbiologic evaluation of deep tissue infections.
Bone samples frequently arrive as small fragments. While acceptable, larger tissue pieces (≥5 mm) enhance sensitivity and improve pathogen recovery.
Specimen Stability Information
Ambient: 24 hours (bone marrow, CSF only)
Refrigerated: 24 hours
Rejected Due To
- eSwab submitted
- Separate specimen collection not submitted (if ordering additional cultures)
- Use of urine preservative
- Sputum >72 hours old
Testing Algorithm
When this test is ordered, the reflex test may be performed at an additional charge. All acid fast bacilli submitted will be identified and billed as appropriate.
Reflex Test
| Reporting Name | Available Separately | Always Performed |
|---|---|---|
| XPERT MTB-RIF | No | No |
| MALDI-TOF | No | No |
Reference Values
Smear: No acid fast bacillus seen
Culture: No Growth
Interpretation
Organisms growing in pure culture are identified to the species level whenever possible.
Cautions
For sputum, collect 3 specimens on 3 consecutive days.
Method Description
Smear
Culture
Susceptibility (if appropriate)
Performing Lab
Clinical Lab University East
Day(s) Performed
Monday through Sunday
Report Available
Smear: 1 day
Culture: 43 days
Reporting Name
AFB Culture
CPT Code Information
87116
87206
87015 (if appropriate)
LOINC Code Information
6463-4