Comparison of Interferon-gamma Assays with the Tuberculin Skin Test in Children / 소아알레르기및호흡기학회지

ABSTRACT

PURPOSE: In vitro interferon-gamma assays have emerged as alternatives to the tuberculin skin test for the diagnosis of latent tuberculosis infection. These assays have been performed on adults, especially in foreign countries. The aim of this study was to investigate the usefulness of interferon-gamma assays in children. METHODS: Between July 2007 and May 2009, we recruited 82 children with suspected latent tuberculosis infections. We performed chest radiography, the tuberculin skin test (2 TU) and the QuantiFERON-TB Gold assay. The volunteers who were positive for the QuantiFERON-TB Gold assay treated for 6 months with isoniazid. After treatment, the QuantiFERON-TB Gold assay was repeatedly performed. RESULTS: Of the 82 participants, 27 had positive QuantiFERON-TB Gold assay results. For the tuberculin skin test, 26 participants were positive at a 10-mm cutoff. With a cutoff point of 15 mm, 14 participants had positive tuberculin skin test results. Data on agreement between the tuberculin skin test and the QuantiFERON-TB Gold assay were available for all children. With a cutoff point of 10 mm, agreement was 86.8%, whereas with a cutoff point of 15 mm, it was 74.4%. The QuantiFERON-TB Gold assay was repeatedly performed on 7 participants, 3 of whom had persistently positive QuantiFERON-TB Gold assay results. CONCLUSION: In our study, it is suggested that the QuantiFERON-TB Gold assay may have good agreement with the tuberculin skin test. Further studies with a larger sample size are needed to evaluate a definitive relationship between the QuantiFERON-TB Gold assay and the tuberculin skin test in children