Tuberculin skin test reactivity and conversions in United States- and foreign-born Latino children

Abstract

The rate of positive tuberculin skin tests for Latino children was examined to help define high risk groups. We reviewed 330 charts of subjects, 18 years of age or younger, with one or more tuberculin (5 tuberculin units, purified protein derivative) skin test readings in a 5-year period. Overall 9% of United States-born and 53% of foreign-born Latinos had positive tuberculin tests (P less than 0.01). Repeat applications identified 35 converters and a greater proportion of United States-born Latinos were in this group (P less than 0.05). Radiographic changes on chest films consistent with active tuberculous disease were found in four of the foreign-born converters. The calculated tuberculin conversion rate of these Latinos is 15 to 30 times that of the United States general population. Unsuspected transmission of tuberculosis may be one possible explanation. We recommend that: clinicians should perform routine tuberculin skin tests in healthy Latino children whether born in the United States or in a foreign country; and active screening for tuberculosis of Latino immigrants by local health departments be conducted with appropriate funding support.