METHODS: We performed a retrospective study of 166 TB patients [68 patients with pulmonary tuberculosis TB (PTB) and 98 patients with extra-pulmonary TB (EPTB)] diagnosed in our hospital between January 2016 and May 2018 along with 377 non-TB patients. The diagnostic performance of the TB-IGRA was evaluated using receiver operating characteristic (ROC) curves. Youden\'s index was used to determine the optimal cut-off threshold.
RESULTS: IFN-γ release in patients with PTB and EPTB were dramatically higher compared with non-TB patients (203.58±18.00 pg/mL, 201.83±14.56 pg/mL and 32.12±4.36 pg/mL, respectively). IFN-γ release was positively correlated with lymphocyte counts and percentages in patients with PTB (r = 0.252 and r = 0.278, respectively) and EPTB (r = 0.229 and r = 0.298, respectively). No correlation was observed in non-TB patients. The area under the ROC curve for TB-IGRA was 0.884. When the optimal cut-off value for IFN-γ (14 pg/mL, Youden\'s index 0.661) was applied, the sensitivity was 88.6% and the specificity was 77.5%.
CONCLUSIONS: Combining TB-IGRA with lymphocyte enumeration was effective for diagnosis of early-stage Mycobacterium tuberculosis infection.
方法:我们对2016年1月至2018年5月在我院确诊的166例肺结核患者[68例肺结核(PTB)和98例肺外肺结核(EPTB)]以及377例非肺结核患者进行了回顾性研究。使用受试者工作特征(ROC)曲线评价TB-IGRA的诊断性能。尤登指数用于确定最佳截止阈值。
结果:PTB和EPTB患者的IFN-γ释放量明显高于非TB患者(203.58±18.00pg/mL,201.83±14.56pg/mL和32.12±4.36pg/mL,分别)。在PTB(分别为r=0.252和r=0.278)和EPTB(分别为r=0.229和r=0.298)患者中,IFN-γ释放与淋巴细胞计数和百分比呈正相关。在非结核病患者中未观察到相关性。TB-IGRA的ROC曲线下面积为0.884。当IFN-γ的最佳临界值(14pg/mL,尤登指数0.661)被应用,敏感性为88.6%,特异性为77.5%.
结论:将TB-IGRA与淋巴细胞计数联合用于诊断早期结核分枝杆菌感染是有效的。