To help detect and identify infections caused by Mycobacterium tuberculosis, the cause of , and other Mycobacterium species, which are known as acid-fast bacilli (AFB); to monitor the effectiveness of treatment
When you have signs and symptoms of a lung infection, such as a cough, weight loss, fever, chills, and weakness, that may be due to TB or a ; when you have a positive and you are in a high-risk group for progressing to active disease; when you have a skin or other body site infection that may be due to ; when you are undergoing treatment for TB
For suspected cases of tuberculosis lung infections, usually three samples are collected early in the morning on different days. If the affected person is unable to produce sputum, a bronchoscope may be used to collect fluid during a procedure called a bronchoscopy. In children, gastric washings/may be collected. Depending on symptoms, urine, an aspirate from the site of suspected infection, , other tissue samples may be submitted for AFB smear and culture.