Clinical and Interpretive

Acid fast smear is used in the detection of acid-fast bacilli in clinical specimens.

Mycobacterium tuberculosis is a leading infectious disease cause of death worldwide. The Centers for Disease Control and Prevention has reported a rise in the incidence of tuberculosis associated with AIDS, foreign-born cases, and increased transmission in high-risk populations. There has also been a rise in the number of Mycobacterium tuberculosisstrains that exhibit resistance to 1 or more antituberculosis drugs. The public health implications of these facts are considerable. Because Mycobacterium tuberculosis is readily spread by airborne particles, rapid diagnosis and isolation of infected persons is important. Nontuberculous mycobacteria infections also cause significant morbidity and mortality in humans, particularly in immunocompromised persons.

Detection of acid-fast bacilli in sputum specimens allows rapid identification of individuals who are likely to be infected with mycobacteria while definitive diagnosis and treatment are pursued.