Three sputum samples are stained and examined for acid-fast bacilli (AFB), the bacteria that cause TB.
Testing multiple samples increases the chance of detecting pulmonary tuberculosis.
Cough for more than 2 weeks, breathlessness, wheezing, fever with chest symptoms, or TB exposure.
No fasting needed.
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Usually on consecutive mornings (or as instructed), coughing deeply from the chest each time.
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 11–35 hours after the sample reaches the lab. You will receive the report online.