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Advanced Diagnostic Laboratories

Smear, Culture, and Identification of M. tuberculosis complex

Test Code



This test includes AFB smear, culture, and identification of Mycobacterium tuberculosis complex from a clinical specimen. Nontuberculous mycobacteria and other partially acid fast organisms are not identified. 

The AFB smear is a direct fluorescent stain from the specimen and can be used to quickly establish the presence of mycobacteria. The AFB culture is the inoculation of a clinical specimen onto multiple media types followed by monitoring for six weeks. Growth of M.tuberculosis complex is identified and speciated to the greatest extent possible.

This test is typically performed for veterinary purposes (e.g. elephants, non-human primates and other animals where M. tuberculosis complex is suspected), but may be used in human cases after discussion with the laboratory.

Nucleic acid amplification testing for M. tuberculosis is not performed. If a complete workup of all AFB is needed, order AFB1. If workup of NTM in particular is desired, order AFB3.