Résumé
Objective To study the feature of MIG and IFN-γ obtained from PBMCs stimulated with Mtb specific antigens and the potential value in the differential diagnosis of active pulmonary tuberculosis from bacterial pneumonia and primary lung cancer. Methods 90 patients with active pulmonary tuberculosis and 31 patients with bacterial pneumonia and primary lung cancer were enrolled. MIG and IFN-γin supernatants from PBMCs stimulated with Mycobacterium tuberculosis-specific antigens were analyzed with Bender Flowcytomix on flow cytometry. The diagnostic values were established based on receiver operating characteristic curve analysis. Results PBMCs stimulated with Mtb-specific antigens produced significantly higher levels of MIG compared with IFN-γ The level of MIG in active pulmonary TB patients was significantly higher than in controls(3023.0 pg/ml vs 112.5 pg/ml, P ＜0.0001). The MIG and IFN-γtests were positive in 96. 8 and 86. 7% of the TB patients, the specificity was up to 94. 4 and 87. 1%. With combination of MIG and IFN-γtests, the positive rate increased among TB patients to 97. 8% without a significant decrease in specificity. Conclusions The responses of the MIG and IFN-γagainst to Mtb-specific antigens could be used to discriminate newly-treated active pulmonary tuberculosis fiom bacterial pneumonia and primary lung cancer. Combination of MIG and IFN-γ might be a simple and quick approach to diagnosis newly-treated active pulmonary tuberculosis.