Tuberculosis screening in internationally adopted children: the need for initial and repeat testing

Abstract

Objective: Because most internationally adopted children come from areas of high tuberculosis prevalence, an initial tuberculin skin test is recommended after arrival to the United States. We evaluated whether repeat testing of children >or=3 months after arrival to the United States would identify additional children with latent tuberculosis infection.

Methods: Internationally adopted children who were seen at our International Adoption Center and had a tuberculin skin test within 2 months of arrival to the United States were eligible for the study. Children not diagnosed with tuberculosis with initial testing were retested at least 3 months later. The prevalence of tuberculosis on arrival and after repeat testing was determined, and potential risk factors for infection were examined.

Results: Of the 527 internationally adopted children with an initial tuberculin skin test completed, 111 (21%) had evidence of latent tuberculosis infection. Repeat tuberculosis testing was complete for 191 internationally adopted children (46.9% of those who had an initially negative tuberculin skin test). Latent tuberculosis infection was found in 20% of those who were retested. No children were found to have active tuberculosis disease. Children with an initially positive tuberculin skin test result had slightly higher weight-for-age z scores at their initial clinic visit, whereas those whose tuberculin skin test result was positive after repeat testing had slightly lower weight-for-age z scores. A strong correlation between BCG immunization and tuberculin skin test result was observed.

Conclusions: Latent tuberculosis infection is common in internationally adopted children. A high proportion of internationally adopted children had an initially false-negative tuberculin skin test. Repeat tuberculosis testing of all internationally adopted children with an initially negative tuberculin skin test should be the standard of care for identifying tuberculosis infection and preventing tuberculosis disease in this high-risk population.