AFB Smear and Culture

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Also known as: TB culture and sensitivity
Formal name: Acid-fast bacillus smear; culture; and sensitivity
Related tests: TB Skin Test

At a Glance

Why Get Tested?

To help identify a mycobacterial infection; to diagnose tuberculosis (TB) or to monitor the effectiveness of treatment

When to Get Tested?

If you have symptoms, such as a long lasting cough, weight loss, fever, chills, and weakness, that your doctor thinks may be due to TB or another mycobacterial infection. If your doctor suspects that you have active TB or wants to monitor the effectiveness of TB treatment.

Sample Required?

Usually, three specially collected spit (sputum) samples are collected early in the morning on different days. If you are unable to produce a sputum sample, a bronchoscope may be used to collect fluid during a procedure called a bronchoscopy. In children, stomach washings/aspirates may be collected. Depending on symptoms, urine, cerebral spinal fluid (CSF), other body fluids, small samples of tissue samples may be biopsied and used to help indentify an infection.

Test Preparation Needed?