A sputum (or other) sample is stained and examined under the microscope for acid-fast bacilli (AFB) — the bacteria that cause tuberculosis.
A rapid test for pulmonary TB in people with cough lasting more than 2 weeks, fever, weight loss or night sweats; also used to monitor TB treatment.
Cough for more than 2 weeks, breathlessness, wheezing, fever with chest symptoms, or TB exposure.
No fasting needed.
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Rinse your mouth with water, take a deep breath and cough deeply from the chest — saliva alone is not suitable.
No fasting is needed. You can eat and drink normally unless your doctor has advised otherwise.
Sputum (deep-cough) sample, ideally first thing in the morning; other samples (fluid, pus) may be used.
Usually within 24–48 hours after the sample reaches the lab. You will receive the report online.