Acid-fast stain

Depending on where the infection may be in your body, your health care provider will collect one of these samples: Urine Stool Sputum Bone marrow Tissue The sample is then sent to a laboratory. Some of the sample is placed on a glass slide, stained, and heated. The cells in the sample hold onto the dye. The slide is…

Preparation depends on how the sample is collected. Your provider will tell you how to prepare.

How much discomfort you may feel depends on how the sample is collected. Your provider will discuss this with you.

The test can tell if you are likely infected with the bacteria that cause TB and related infections.

A normal result means no acid-fast bacteria were found on the stained sample. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test result.

Abnormal results may be due to: TB Leprosy Nocardia infections (also caused by a bacteria)

Risks depend on how the sample is collected. Ask your provider to explain the risks and benefits of the medical procedure.

Fitzgerald DW, Sterling TR, Haas DW. Mycobacterium tuberculosis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases . 9th ed. Philadelphia, PA: Elsevier; 2020:chap 249. Rodino KG, Woods GL, Wengenack NL. Mycobacteria. In: McPherson RA, Pincus MR,…