TY - JOUR T1 - Utility of quantitative T-cell responses <em>versus</em> unstimulated interferon-γ for the diagnosis of pleural tuberculosis JF - European Respiratory Journal JO - Eur Respir J SP - 1118 LP - 1126 DO - 10.1183/09031936.00005309 VL - 34 IS - 5 AU - K. Dheda AU - R. N. van Zyl-Smit AU - L. A. Sechi AU - M. Badri AU - R. Meldau AU - S. Meldau AU - G. Symons AU - P. L. Semple AU - A. Maredza AU - R. Dawson AU - H. Wainwright AU - A. Whitelaw AU - Y. Vallie AU - P. Raubenheimer AU - E. D. Bateman AU - A. Zumla Y1 - 2009/11/01 UR - http://erj.ersjournals.com/content/34/5/1118.abstract N2 - The clinical utility of antigen-specific interferon (IFN)-γ release assays (IGRAs) using pleural mononuclear cells, for the diagnosis of tuberculosis (TB), requires clarification. We compared the diagnostic utility of unstimulated pleural IFN-γ levels with several pleural antigen-specific T-cell IGRAs (early secretory antigenic target-6 and culture filtrate protein-10 (T-SPOT.®TB, QuantiFERON®-TB Gold In-tube), purified protein derivative (PPD) and heparin-binding haemagglutinin (HBHA)) in 78 South African TB suspects. Test results were compared against a clinical score and a reference standard. Out of 74 evaluable subjects 48, seven and 19 had definite, probable and no TB, respectively. 11 (15%) out of 74 pleural samples (nine (19%) out of 48 of the definite TB cases) had total cell counts that were inadequate for T-cell processing. In the remaining 63 samples, the sensitivity, specificity, positive predictive value and negative predictive value of different diagnostic methods were as follows. Maximal bioclinical score: 54, 89, 92 and 43%, respectively; T-SPOT.®TB: 86, 60, 84 and 64%, respectively; QuantiFERON®-TB Gold In-tube: 57, 80, 87 and 44%, respectively; HBHA-specific IGRA: 59, 31, 64 and 27%, respectively; PPD-specific IGRA: 81, 40, 76 and 46%, respectively; and pleural fluid unstimulated IFN-γ: 97, 100, 100 and 94%, respectively. Unstimulated IFN-γ was the most accurate test for distinguishing TB from non-TB effusions in a high-burden setting. The antigen-specific T-cell IGRAs were limited by suboptimal accuracy and the inability to isolate sufficient mononuclear cells to perform the assay. ER -