What is the role of nucleic acid amplification testing (NAAT) in TB testing?

• A. NAAT alone confirms TB
• B. NAAT supports TB diagnosis but culture positivity is still required
• C. NAAT is not used in TB testing
• D. NAAT excludes TB

Answer: (B)

NAAT speeds up TB diagnosis by quickly detecting M. tuberculosis genetic material in a specimen, which helps with rapid treatment decisions and infection control, especially when smear results are negative. But it does not by itself confirm TB. A positive NAAT should be followed by culture to confirm the diagnosis and to perform comprehensive drug susceptibility testing. Culture remains the gold standard for confirmation and for determining the full resistance pattern, and some NAATs (like those that test for rifampin resistance) provide additional but not complete resistance information. For these reasons, NAAT supports diagnosis and accelerates management, but culture positivity is still required.