Prospective comparison of tuberculin skin test and QuantiFERON-TB Gold In-Tube assay for the detection of latent tuberculosis infection among healthcare workers in a low-incidence setting.

We compared the results of the tuberculin skin test with the results of the QuantiFERON-TB Gold In-Tube (QFT-GIT) assay among 182 low-risk healthcare workers. Overall agreement and specificity were high, but the tests did not agree on positive results. Only 2 of 5 positive QFT-GIT assay results could be confirmed with repeat analyses. Indeterminate results were associated with potential immunosuppression.