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Acid Fast Bacilli (AFB) Culture, Non-sterile sources (8000100040)
Test Mnemonic:
Specimen Requirements:

Collect specimens in a sterile, leak-proof container.  It is recommended to collect 3 sputum specimens to diagnose tuberculosis, preferable volume >5ml. For sputum collection, use the sputum collection kit. Collect complete first morning urine for AFB culture.

Specimens for testing: Sputum, respiratory sources, gastric aspirates, feces, autopsy sources, abscesses, skin lesions, urine samples. Swabs are not recommended for optimal recovery of AFB.


Sterile containers

Minimum Volume:

Sputum - 1ml; Urine- first morning collection (>30ml) for optimum sensitivity


Transport to the laboratory as soon as possible after collection. Refrigerate specimens if transport is delayed. Deliver gastric aspirates as soon as possible due to pH changes


72 hours

Causes for Rejection:

More than three samples per week submitted on the same patient (respiratory sources only), leaking container, insufficient quantity, more than two feces per week. Specimen container unlabeled or labeled incorrectly. No date and time of collection on requisition form.

Reference Range:

No Mycobacteria isolated

Turnaround Time:

Samples are processed 5 days per week. Smear is reported the day of processing; positive cultures are reported when growth and negative cultures are held 6 weeks. Cultures are incubated for 6 weeks.


Acid fast smear, culture for the isolation and identification of Mycobacterium species and antimicrobial susceptibility testing when appropriate



Clinical Microbiology


AFB Culture; Culture, AFB; Respiratory AFB Culture; AFB Culture, Sputum; TB Culture; AFB CUlture, Urine; AFB Culture, Feces

Clinical Indication:

Cultivation of Mycobacterium spp. from non-sterile sources or if Mycobacterium tuberculosis or other Mycobacteria spp. suspected.

Patient Preparation :

Productive cough

CPT 4 Code:

 87116 - culture, 87206 - smear, 87015 - concentration, additional if indicated


The first positive AFB smear or culture for acid-fast bacilli from respiratory sources is a critical value and the LIP is notified.

It is recommended to collect sputum samples 8-24 hours apart and the first morning urine for optimal recovery. The first positive smear from respiratory sources with AFB is considered a critical value.

When ordering tests for which Medicare or Medicaid reimbursement will be sought, physicians should only order tests that are medically necessary for the diagnosis or treatment of the patient. Components of the organ or disease panels may be ordered individually. The diagnostic information must substantiate all tests ordered and must be in the form of an ICD-10 code or its verbal equivalent.
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