Background and objective The aim of this study was to determine the prevalence of tuberculosis infection in undocumented immigrant teenagers using a tuberculin skin test (TST) for initial screening and QuantiFERON®-TB Gold In-Tube (QFT-GIT) as a confirmatory test. Patient and method From 2007 to 2012, under 19 year-old immigrant teenagers from 2 accommodation centers of the Basque Country (Spain) were included in the study. The TST was done in all of them and the QFT-GIT was done in selected patients with a TST ≥ 5 mm. Results Eight hundred and forty-five immigrants were included, most of them from Africa (99.5%). Fifty-one percent of immigrants with TST ≥ 5 mm has a positive QFT-GIT. We found 2 cases of active tuberculosis (2/845: 0.24%). The concordance between TST (≥ 10 mm) and QFT-GIT was 63%, with 57% of positive concordance cases and 96% of negative concordances. There were 246 cases with TST ≥ 10 mm (29%), with significant differences between Magrebis (21.5%) and Subsaharians (67%) (P <.001). Vaccination with Calmette-Guéin bacille was an independent predictor for having a TST ≥ 10 mm (OR: 2.11; P <.001) and for the discordance TST+/QFT-GIT-, both for a TST ≥ 5 and a TST ≥ 10 mm (OR 2.16, 95% confidence interval [95% CI] 1.46-3.20, and OR 1.91 95% CI 1.23-2.97, respectively). The positive value of QFT-GIT increased significantly as the TST increased, with a positive association in all the cut-off points analyzed: 10-14 mm (OR 7.95, 95% CI 1.79-35.33), 15-19 mm (OR 35, 95% CI 7.93-154.52) and ≥ 20 mm (OR 91.3, 95% CI 18.20-458.11). Conclusion Due to the high prevalence of latent tuberculosis infection in Subsaharian immigrants, we recommend implementing screening programs in this population. Using QFT-GIT, the number of candidates for chemoprophylaxis was reduced to 43% compared with TST alone (≥ 10 mm). © 2013 Elsevier España, S.L.U.

QuantiFERON® Gold In-Tube Teenagers Tuberculin skin test immigrants

prospective study immigrant Mycobacterium tuberculosis test kit Africa south of the Sahara multicenter study mass screening clinical trial Prospective Studies human validation study statistics and numerical data interferon gamma release assay Interferon-gamma Release Tests BCG vaccine ethnology procedures Cross-Sectional Studies cross-sectional study migrant Humans Adolescent male Emigrants and Immigrants latent tuberculosis Spain tuberculosis reproducibility Reproducibility of Results prevalence Article tuberculin test normal human chemoprophylaxis Immunoenzyme Techniques vaccination enzyme immunoassay