Performance of a Whole-Blood Interferon-Gamma Release Assay with Mycobacterium RD1-Specific Antigens among HIV-Infected Persons

Objective. To evaluate the usefulness of one of IGRAs, QuantiFERON-TB Gold (QFT-G), in human immunodeficiency virus- (HIV- ) infected patients with various CD4+ T cell counts. Methods. The QFT-G assay was performed using QFT-G kits among 107 HIV-infected patients including 9 cases with active tuberculosis (TB). Results. In HIV-infected patients with CD4+>50/μL, QFT-G positive rate for active TB patients was 5/6 (sensitivity =83%), and that for those without active disease was 1/69 (specificity =99%). The frequency of indeterminate QFT-G test was significantly higher in those with CD4+ less than 50/μL (P