An alternative to 'two-step' tuberculin skin testing for Southeast Asian refugees

Previous studies report that Southeast Asian refugees demonstrate very high incidences of positive reactions to two-step tuberculin testing. In spite of these findings, fiscal restraints have limited the use of two-step testing in some of the centers that screen large numbers of these refugees. In this study, 101 Southeast Asian refugees were studied for their antigenic response to the tuberculin skin test. Forty-nine had positive reactions when the tuberculin skin test was read at 48 hours. Of the 52 refugees who showed a negative reaction at 48 hours, 22 had positive reactions when read a second time, three to five days later. The 28 refugees with negative reactions at both 48 hours and at five to seven days underwent two-step tuberculin testing. Only two of the 28 demonstrated positive reactions with two-step testing. Of the refugees with positive reactions at 48 hours, all but one continued to show positive reactions when the skin test was read a second time, at five to seven days. These findings suggest that a single tuberculin skin test, read at five to seven days, may provide a cost-effective alternative to two-step tuberculin testing for Southeast Asian refugees.