TB on the rise among international adoptees

By Anne Harding

NEW YORK (Reuters Health) - Tuberculosis infection is on the rise among internationally adopted children, a new study shows.

"These children do have significant risk to be infected with mycobacterium tuberculosis," Dr. Anna M. Mandalakas of Case Western Reserve University in Cleveland, Ohio, the study's lead author, told Reuters Health. "They definitely need to be screened for TB infection."

The findings underscore the importance of current guidelines that recommend children be screened for TB immediately after adoption, Mandalakas and her colleagues note in the September issue of Pediatrics.

International adoptions tripled between 1989 and 2005 and more and more children are coming from "resource-poor" government orphanages in China and the former Soviet Union, where they may run a greater risk of being exposed to TB.

To investigate the prevalence of TB infection among international adoptees, the researchers looked at 880 children who were screened for TB at the University of Minnesota's International Adoption Clinic between 1986 and 2001.The children came from 33 different countries.

Overall, 12 percent tested positive for TB, the researchers found, and the prevalence of TB infection among adoptees rose by 7 percent for each year of the study. Among children younger than 24 months, prevalence of TB infection rose by 15 percent a year. These young children also were at greater risk of acquiring the infection than were older adoptees.

Children younger than 2 years spend the most time indoors with caregivers who may have active TB disease, which is likely why they were at greater risk of becoming infected than older children, the researchers suggest.

Mandalakas and her colleagues also found evidence for chronic malnutrition in 28 percent of the children and acute malnutrition in 5 percent.

"The fact that many children in the current study also were malnourished puts them at considerable risk of progression to tuberculosis disease," Mandalakas said in an interview.

She and her colleagues urge that orphanages begin to screen staff for TB infection and for active disease, both for the health of children who are adopted and for those who remain in the orphanages.

SOURCE: Pediatrics, September 2007.