What is the Mantoux test also known as?

• A. Tuberculin skin test (TST).
• B. Interferon-gamma release assay.
• C. Chest X-ray.
• D. Sputum culture.

Answer: (A)

The Mantoux test is the tuberculin skin test (TST) used to detect TB infection. It’s performed by injecting a small amount of purified protein derivative (PPD) into the skin and then checking the injection site 48–72 hours later for induration, which reflects a delayed-type hypersensitivity to TB antigens. A positive result indicates TB exposure or infection, but it cannot distinguish latent infection from active disease. Other options listed are different tests: an interferon-gamma release assay is a blood test for TB immune response, a chest X-ray looks for signs of active disease, and a sputum culture identifies TB bacteria in respiratory samples.