, 2010; Rangaka et al., 2012). The QuantiFERON TB Gold In-Tube test (QFT-GIT) uses an ELISA to measure the amount of IFN-γ released in response to specific M.tb antigens compared with controls. The specific M.tb antigens are early
secretory antigenic MAPK inhibitor target-6 (ESAT-6), culture filtrate protein 10 (CFP-10) and TB 7.7, which are present in all M.tb and are able to stimulate the measurable release of IFN-γ in most infected persons, but which are absent from BCG vaccine strains and most nontuberculous mycobacteria (Andersen et al., 2000). Thus, as test antigens, these proteins offer improved test specificity compared with purified protein derivative (PPD). In August 2008, QFT-GIT became the second IGRA approved by the US Food and Drug Administration (FDA) as an aid for diagnosing M.tb infection (FDA, 2010). However, the usefulness of QFT-GIT in the diagnosis of tuberculous High Content Screening pleurisy in developing countries, especially in China and other regions with mandatory BCG-vaccinated coverage, remains unclear. Research has shown that use of molecular biologic technology to detect M.tb-specific fragments in pleural effusion-specific fragments, could improve the diagnostic sensitivity and specificity for tuberculous pleurisy (Anie et al., 2007; Liu et al., 2007; Kumar et al., 2010). However, in previous
studies, diverse methods with different primers were selected to detect M.tb in pleural fluid samples, demonstrating highly variable sensitivities (42.8–87.0%) and specificities (91–97%; Nagesh et al., 2001; Hasaneen et al.,
2003; Chakravorty et al., 2005; Moon et al., 2005; Light, 2010). To evaluate the diagnostic accuracies of QFT-GIT and nested-PCR in tuberculous pleurisy, we conducted a cross-sectional study in high TB epidemic regions of China. The aim was to provide evidence of the usefulness of QFT-GIT and nested-PCR in tuberculous pleurisy diagnosis in a BCG-vaccinated area and give clues as to the development of in-house M.tb-specific detection tools. Seventy-eight patients with pleural effusion were enrolled consecutively in this cross-sectional study from 1 January 2011 to 31 October 2011 in Wuxi No. 5 People’s Hospital. Confirmed tuberculous PTK6 pleurisy was diagnosed with M.tb cultures positive in pleural effusion and/or confirmed TB infection by pleural biopsy. Probable tuberculous pleurisy was diagnosed using one of the following criteria: M.tb culture positive in sputum; M.tb culture positive in other biologic specimens; positive response to antituberculosis medication without other possible causes of pleural effusion (Moon et al., 2005). Twenty patients with pleural effusion who were diagnosed with diseases other than TB were also enrolled in this study as controls. The QFT-GIT was performed according to the manufacturer’s instructions (QFT-GIT; Cellestis Ltd, Carnegie, Australia).