Tuberculin skin tests (TSTs) and interferon-γ release assays (IGRAs) are intended for the diagnosis of tuberculosis (TB) infection, not active disease Tuberculin skin tests and IGRAs detect evidence of immunity to TB antigens but cannot distinguish TB infection from disease. Negative results do not exclude TB disease, as false negatives may occur for several reasons, including illness-induced anergy.1 Therefore, TSTs and IGRAs should be avoided in adults in whom TB disease is suspected.