AFB Smear and Culture: At a Glance

Why get tested?
To help identify a mycobacterial infection; to diagnose tuberculosis (TB) ; to monitor the effectiveness of treatment

When to get tested?
If you have symptoms, such as a chronic cough, weight loss, fever, chills, and weakness, that may be due to TB or another mycobacterial infection; if your doctor suspects that you have active TB; if your doctor wants to monitor the effectiveness of TB treatment

Sample required?
Usually, three sputum samples are collected early in the morning on different days. If the patient is unable to produce sputum samples, a bronchoscope may be used to collect fluid during a procedure called a bronchoscopy. In children, gastric washings/aspirates may be collected. Depending on symptoms, urine, cerebral spinal fluid (CSF), other body fluids, or biopsied tissue samples may be submitted for culture