title: Diagnostic performance of whole-blood interferon-γ assay and enzyme-linked immunospot assay for active tuberculosis'.
abstract: The aim of this study was to compare the diagnostic performance of 2 interferon-γ release assays, an enzyme-linked immunospot assay (T-SPOT.TB; Oxford Immunotec Ltd., Oxford, UK) and the QuantiFERON-TB Gold in-Tube assay (QFT-GIT; Cellestis Ltd., Carnegie, Australia), in patients with suspected active tuberculosis (TB). From October 2009 to October 2011, a total of 200 patients with suspected TB were enrolled. Clinical and microbiological characteristics of the patients were collected and blood samples were obtained for T-SPOT.TB and QFT-GIT assays. Among the 200 subjects, 98 (49%) had culture-confirmed TB, 18 (9%) had probable TB, and the remaining 84 (42%) subjects did not have TB. The sensitivity, specificity, positive predictive value, and negative predictive value for active TB diagnosis by the T SPOT. TB were 83%, 71%, 81%, and 75%, respectively. For QFT-GIT, the sensitivity, specificity, positive predictive value, and negative predictive value for active TB diagnosis were 66%, 76%, 80%, and 62%, respectively. The QFT-GIT assay resulted in more indeterminate and false-negative results than the T-SPOT.TB assay, especially in immunocompromised patients. In conclusion, T-SPOT.TB had a higher sensitivity and resulted in fewer indeterminate results than the QFT-GIT assay for diagnosing active TB.
authors.affiliation: Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan, 736.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Lai
authors.forename: Che-Kim
authors.initials: CK
authors.lastname: Tan
authors.forename: Sheng-Hsiang
authors.initials: SH
authors.lastname: Lin
authors.forename: Chun-Hsing
authors.initials: CH
authors.lastname: Liao
authors.forename: Yu-Tsung
authors.initials: YT
authors.lastname: Huang
authors.forename: Po-Ren
authors.initials: PR
authors.lastname: Hsueh
mesh_terms: D000328:Adult; D000368:Aged; D058501:Enzyme-Linked Immunospot Assay / Q000379:methods*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood*; D059425:Interferon-gamma Release Tests / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000472:pathogenicity; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011933:Reagent Kits, Diagnostic; D013624:Taiwan; D014376:Tuberculosis / Q000175:diagnosis* / Q000473:pathology
chemical_list: D011933:Reagent Kits, Diagnostic; D007371:Interferon-gamma