Acid-fast (Mycobacteria) Smear and Culture With Reflex to Identification and Susceptibility Testing
Also known as: Blood Mycobacteria Culture, Culture, Acid-Fast (Sputum, Tissue, Urine, and Gastric Contents), Culture, Blood, Mycobacteria, Mycobacteria Culture (Sputum, Tissue, Urine, and Gastric Contents)
Use
Isolate and identify mycobacteria and determine susceptibility to antimycobacterial drugs
Special Instructions
Specimen processing may involve N-acetyl-L-cystine-sodium hydroxide treatment or equivalents. Smear and culture testing are separate and have specific specimen processing requirements. Special culture conditions are required for certain mycobacteria like Mycobacterium marinum, Mycobacterium haemophilum, and Mycobacterium genavense. Notification of suspected pathogens is necessary for appropriate cultivation.
Limitations
Susceptibility testing may not be possible if the organism does not grow in culture. Mixed cultures cannot undergo susceptibility testing. Biopsy or body fluid cultures are often better for diagnosing tuberculosis in smear-negative cases. Certain mycobacteria like Mycobacterium marinum require specific conditions for successful culture, and the laboratory must be informed for special handling. Testing in bronchoscopy specimens may be impacted by the presence of topical anesthetics.
Methodology
Culture-based
Biomarkers
LOINC Codes
- 50941-4
- 51098-9
- 11545-1
- 50941-4
Result Turnaround Time
43-56 days
Related Documents
For more information, please review the documents below
Specimen
Sputum
Volume
5-10 mL
Minimum Volume
2 mL
Container
Sterile container with tight screw-cap seal
Collection Instructions
Collect first morning sputum, not saliva, in three separate specimens on three separate days.
Storage Instructions
Refrigerate specimen. If splitting is necessary for other tests, divide at collection so each is at appropriate temperature.
Causes for Rejection
Inadequate quantity, inappropriate container, prolonged delay, leaking container, unlabeled specimen, or incorrect specimen source.
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 7 days |