Tuberculin

Tuberculin is a substance derived from the bacteria that cause tuberculosis. It’s used in diagnostic tests to determine if someone has been exposed to TB bacteria. When injected into the skin, if a person has been previously exposed or vaccinated, their immune system reacts, causing a small bump or redness at the site within 48 to 72 hours. This reaction indicates prior exposure, but additional tests are needed to confirm active infection. Tuberculin tests are helpful tools for identifying potential TB cases, guiding further medical evaluation and treatment.