A positive Mantoux test indicates what?

• A. Presence of TB bacteria but not necessarily active TB
• B. Active TB disease
• C. Immunity to TB
• D. Liver damage due to TB treatment

Answer: (A)

The Mantoux test is a skin test that shows whether someone has been exposed to tuberculosis and has a delayed-type hypersensitivity response to TB proteins. A positive result means there has been TB infection at some point, so the person may have latent TB infection or, less commonly, active TB disease. It does not prove that bacteria are currently causing illness, nor does it indicate immunity or liver damage from treatment. To determine whether TB is active, further tests such as sputum studies and chest imaging are needed.