Acid Fast Bacilli Referred Isolate Identification

Laboratory Fee Schedule

Procedure: MAC0055A

CPT: 87143

Acid Fast Bacilli Referred Isolate Identification
Synonym(s): AFB Isolate
Requisition Form G-MYCO
Test Description Identification of mycobacterial isolates referred to DSHS Laboratory
Pre-Approval Needed N/A
Supplemental Information Required N/A
Supplemental Form(s) N/A  
Performed on Specimens from (sources) Pure isolate from human sources
Sample/Specimen Type for Testing Mycobacterium species pure isolate in liquid or on solid culture medium
Minimum Volume/Size Required

•   Liquid culture - 2.0 mL

•   Solid culture - Single mature colony

Storage/Preservation Prior to Shipping Ambient
Transport Medium N/A
Specimen Labeling

•   At least 2 patient specific identifiers:  First and last name as one identifier and a DOB or a unique patient specific identifier (e.g. Medical records number).

•   Specimen identification must match specimen submission form.

Shipping and Specimen Handling Requirements

•   Ship according to Dangerous Goods Regulations, IATA, and/or CFR 49

•   Category B shipping applies for unidentified isolates

•   Category A shipping applies for Mycobacterium tuberculosis complex isolates


•   High performance liquid chromatography (HPLC)

•   Subculture for purity and morphological examination

Turn-around Time 2 days for identification

•   HPLC may only detect the predominant organism in a mixed culture.

•   Liquid cultures must be instrument positive in order to analyze by HPLC.

•   Additional testing methods may need to be used to provide definitive identification.

Common Causes for Rejection

•   Cultures overgrown by contaminating organisms

•   Cultures broken in transit

Additional Information

•   Most isolates can be identified as either M. tuberculosis complex or Mycobacterium species, not M. tuberculosis within 2 to 3 days.

Last updated January 9, 2019