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AFB Culture (10005559)
Test Mnemonic:


Specimen Requirements:
Test Included:

Mycobacterial culture, stain for acid-fast bacilli, antimycobacterial susceptibility on Mycobacterium tuberculosis isolates, PCR to detect M.tuberculosis from first occurrence of isolation.


Collect specimens in a sterile, leakproof container. It is recommneded to collect 3 sputum specimens to diagnose tuberculosis.

Urine samples, collect complete first morning voided urine.

Collect blood and bone marrow via syringe and inoculate he Myco?F lytic blood culture bottle (order C MAF).

Other samples such as other respiratory sources, feces, skin lesions, tissues, biopsy material, etc. - place in a sterile container.


Sterile container

Minimum Volume:

Sputum - 3 ml. Urine - 10ml, others- 0.5 grams


Transport to the Microbiology laboratory as soon as possible after collection.

Specimen Preparation:

Refrigerate if there will be a delay in transport, except CSF and blod. Keep them at room temperature.


Room temperature - 8 hours; Refrigerated - 3 days

Causes for Rejection:

More than three samples per week submitted on the same patient (respiratory sources). Feces on patients other than HIV+; leaking containers, insufficient volume to test; samples submitted on swabs; Samples that are unlabeled or mislabeled; no date and time of collection or no collector information on order.

Reference Range:

No acid-fast bacilli isolated

Turnaround Time:

Samples are processed 5 days per week. The AFB smear is reported the day of processing; positive cultures are reported when growth is detected. Cultures are held 6 weeks before final report is issued.


Acid-fast stains, cultures


Clinical Microbiology


Culture, mycobacteria; TB culture; Acid fast bacilli Culture; Mycobacterium tuberculosis culture

Clinical Indication:

Suspected infection with mycobacteria from any site.

CPT 4 Code:

87116 (culture); 87015(concentration); 87206 (stain); 87188 (drugs, each)


For respiratory sources, the first positive AFB smear is considered to be 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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