What does a positive AFB test mean?

A positive AFB (acid-fast bacilli) test indicates the presence of acid-fast bacteria, most commonly Mycobacterium tuberculosis, which is the causative agent of tuberculosis (TB). This test is often performed on sputum samples or other body fluids to diagnose TB infection. A positive result suggests active or latent TB, prompting further investigation and appropriate treatment. However, false positives can occur, so additional testing may be necessary to confirm the diagnosis.