TST-Negative Individuals Do Not Lack Anti-Mycobacterial Responsiveness

Abstract

Tuberculin-skin-test (TST) is widely used for the diagnosis of Tuberculosis. Negative TSTs are occasionally found in individuals vaccinated or infected by Mycobacterium tuberculosis. We show that false negative results are due to a lack of the Tuberculin-specific immune response as replacing tuberculin by unselected M. tuberculosis antigens im- proved the efficiency of the assay.