A nurse is caring for a school-age child who underwent a tuberculin skin test 3 days ago and has a 3-mm induration at the test site. The nurse should identify this finding as which of the following?

A. Disseminated disease: Disseminated tuberculosis refers to widespread infection affecting multiple organs and is diagnosed through clinical findings, imaging, and laboratory tests. A small localized induration on a tuberculin skin test does not indicate disseminated disease. B. A negative result: An induration of 3 mm is considered negative in most populations, including school-age children without specific risk factors. Positive results generally require larger induration measurements depending on risk status, so this finding indicates no significant immune response to the test. C. Active tuberculosis: Active tuberculosis is diagnosed based on symptoms, radiographic findings, and microbiologic evidence. A minimal induration on a tuberculin skin test alone does not confirm active disease. D. An allergic reaction: Allergic reactions typically present with redness, itching, or swelling without firm induration. The measurement of induration, not redness, is used to interpret the tuberculin skin test result.