结核T细胞斑点试验在结核性胸膜炎中的价值

T cell enzyme-linked immunospot tuberculous test for tuberculous pleurisy

目的：探讨结核感染T细胞斑点试验（T-SPOT.TB）在鉴别诊断结核性胸膜炎和其他淋巴细胞为主的渗出性胸腔积液中的价值。方法：对63例淋巴细胞为主的渗出性胸腔积液患者（32例结核性胸膜炎，31例非结核性胸膜炎）的外周血和胸腔积液单核细胞（PBMCs，PEMCs）进行T-SPOT.TB检测，评价其敏感性、特异性，并应用ROC曲线分析临界值。结果：结核性胸膜炎患者胸腔积液T-SPOT.TB的敏感性为93.75%，高于外周血的90.63%，但无统计学意义（χ^2=0.21,P=0.641）；特异性为90.32%，明显高于外周血的67.74%（χ^2=4.76，P=0.029）。胸腔积液与外周血检测形成细胞数为532.5（260.5～1053）SFCs/106PEMC vs 166（43.5～349） SFCs/106PBMC（P〈0.05）。胸腔积液的ROC曲线下面积为0.964，当取值分别为12和133 SFCs/106PEMC时，敏感性分别为93.8%和81.3%，特异性为90.3%和96.8%。结论：胸腔积液T-SPOT.TB在结核性胸膜炎诊断中具有重要的参考价值，当斑点数≥133 SFCs/106PEMC特异性较高。

Objective：To investigate the application of mycobacterium tuberculosis T cell enzyme-linked immunospot tuberculous test （T-SPOT.TB） in the diagnosis of tuberculous pleurisy and lymphocyte-predominant pleural exudates. Methods：The peripheral blood mononuclear cells （PBMCs） and pleural effusion mononuclear cells （PEMCs） were separated from 63 patients with lymphocyte-predominant pleural exudates （32 patients of tuberculous pleurisy and 31 patients of non-tuberculous pleurisy）. Sensitivity and specificity were also detected. The optimum cut-off points acquired from the optimal sensitivity-specificity balance in the Receiver Operating Characteristic curves （ROC curves） were constructed. Results：In patients with tuberculous pleurisy, the sensitivity of T-SPOT.TB to pleural effusion was 93.75%, which was significantly higher than that to peripheral blood （90.63%） but no significant difference was found （χ^2=0.21, P=0.641）. The specificity of T-SPOT.TB to pleural effusion was 90.32%, which was higher than that to peripheral blood （67.74%）, （χ^2=4.76, P=0.029）. The frequencies of specific T cells detected by T-SPOT.TB for pleural effusion were significantly higher than for peripheral blood [532.5（260.5-1053）SFCs/106PEMC vs 166（43.5-349） SFCs/106PBMC]（P〈0.05）. Taking 12 and 133 SFCs/106 PEMC as the cut-off value, the sensitivities, specificities and area under curve of T-SOPT.TB were 93.8%and 81.3%, 90.3%and 96.8%, and 0.964, respectively. Conclusion：The T-SPOT.TB assay of pleural effusion could have great importance for the diagnosis of tuberculous pleurisy, and it has higher specificity when the frequencies of specific T cells≥133SFCs/106 PEMC.