Dr. Jim Stimpson, associate dean of academic affairs and professor at the CUNY Graduate School of Public Health and Health Policy and colleagues used nationally representative population data on tuberculosis infection to characterize concordance between the tuberculin skin test and the QuantiFERON(®)-TB Gold In-Tube blood test for immigrants in the United States. The work is published in Public Health Reports.
[Photo: Dr. Jim Stimpson]
The authors used tuberculosis screening data from the 2011-2012 National Health and Nutrition Examination Survey to examine concordance between the tuberculin skin test and the QuantiFERON(®)-TB Gold In-Tube blood test for 7,097 U.S. natives, naturalized citizens, and noncitizens.
Consistent with prior findings, one in five immigrants in the survey was identified with latent tuberculosis infection, a rate 14 times higher than for U.S. natives. They also found higher rates of discordant the tuberculin skin test and the QuantiFERON(®)-TB Gold In-Tube results among immigrants than among U.S. natives. Unadjusted discordance between the two tests was 3 percent among U.S. natives but ranged up to 19 percent for noncitizens. Adjusting for age, sex, and race/ethnicity, noncitizens had more than nine times the odds of having a positive tuberculin skin test result but negative QuantiFERON(®)-TB Gold In-Tube result compared with U.S. natives.
The researchers’ findings suggest that whether and how either of these tests should be deployed is highly contextually sensitive. Significant discordance in test results when used among immigrants raises the possibility of missed opportunities for harm reduction in this already at-risk population. However, they found little distinction between the tests in terms of diagnostic outcome when used in a U.S. native population, suggesting little benefit to the adoption and use of the QuantiFERON(®)-TB Gold In-Tube test in place of tuberculin skin test on the basis of test performance alone for this population.