The tuberculin skin test is performed to evaluate whether a person has been exposed to tuberculosis. If there has been a prior exposure, antibodies are formed and remain in the body. During the skin test, the tuberculosis antigen is injected under the skin and if antibodies are present, the body will have an immune response. There will be an area of inflammation at the site of the injection.
Review Date 12/4/2022
Updated by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.