结核感染T细胞斑点试验对使用免疫抑制剂患者并发肺结核的诊断价值

目的 探讨结核感染T细胞斑点试验(T-SPOT.TB)对使用免疫抑制剂患者并发肺结核的诊断价值。方法 收集2013年7月至2015年12月广州市胸科医院收治的197例使用免疫抑制剂并发肺结核患者(简称“观察组”),及同期住院的200例未使用免疫抑制剂的肺结核患者(简称“对照组”)作为研究对象。所有患者均通过痰液或支气管灌洗液(BALF)的涂片或培养查找抗酸杆菌,对阳性菌株行菌种鉴定以排除非结核分枝杆菌,结合胸部X线摄影检查符合活动性肺结核表现,肺结核诊断均符合《肺结核诊断和治疗指南》标准。比较两组患者血T-SPOT.TB、抗酸杆菌金胺O荧光染色涂片镜检(简称“金胺O涂片镜检”)、BACTEC MGIT 960液体培养(简称“MGIT 960”),以及结核菌素纯蛋白衍生物试验(PPD试验)检测阳性率的差异。采用SPSS 19.0软件对计数资料进行χ ²检验,以P<0.05为差异有统计学意义。 结果 观察组与对照组患者的血T-SPOT.TB检测阳性率分别为85.28%(168/197)、96.00%(192/200)]均明显高于金胺O涂片镜检36.55%(72/197)、35.50%(71/200)](χ ²值分别为98.24、162.53,P值均=0.000),MGIT 960 53.81%(106/197),57.50%(115/200)](χ ²值分别为46.06、83.06,P值均=0.000),PPD试验34.52%(68/197),63.50%(127/200)](χ ²值分别为105.66、65.40,P值均=0.000)。观察组患者T-SPOT.TB、PPD试验检测阳性率均明显低于对照组(χ ²值分别为13.50、33.36,P值均=0.000)。 结论 在使用免疫抑制剂患者并发肺结核时采用血T-SPOT.TB技术进行检测仍具有较高的阳性率,较传统的检测方法具有更高的辅助诊断价值。

Diagnostic value of T-SPOT.TB method in detection of pulmonary tuberculosis in patients receiving immuno-suppression

Objective To explore the diagnostic value of T-SPOT.TB test in detection of pulmonary tuberculosis (PTB) among the patients receiving immuno-suppressive agents.Methods A total of 197 patients, who stayed at the inpatients department of Guangzhou Chest Hospital for receiving immunosuppressive agents treatment from Jul. 2013 to Dec. 2015 and were also diagnosed to be complicated with PTB, were enrolled in this study as the “Observation group”, while 200 PTB cases who stayed at the inpatients department of the same hospital at the same period were enrolled as the “Control group”. All enrolled patients were acid-fast bacillus (AFB) smear microscopy or culture positive with the specimens of their sputum or bronchoalveolar lavage fluid (BALF); in order to exclude NTB, the identification of Mycobacterium tuberculosis (MTB) was performed to culture positive isolates; the images of their chest X-rays were also consistent with the features of active PTB. The diagnosis of PTB for all enrolled patients was consistent with the standards of the Guideline for Pulmonary Tuberculosis Diagnosis and Treatment. The following test results (positive rate) between the two groups were compared: T-SPOT.TB test, AFB fluorescence stain microscopy of Auramine O, BACTEC MGIT 960 liquid culture (MGIT 960) and purified protein derivate (PPD) skin test. SPSS 19.0 software was used for calculation of χ ² test and P<0.05 was regarded as statistical significance. Results The positive rate of T-SPOT.TB was 85.28% (168/197) in the Observation group and 96.00% (192/200) in the Control group respectively; which was significantly higher than that of AFB fluorescence stain microscopy of Auramine O (36.55% (72/197) in the Observation group and 35.50% (71/200) in the Control group; χ ² was 98.24 in the Observation group and 162.53 in the Control group respectively (Ps=0.000)). The positive rates of T-SPOT.TB in the two groups were significantly higher than those of MGIT 960 culture (53.81% (106/197) in the Observation group and 57.50% (115/200) in the Control group; χ ² was 46.06 in the Observation group and 83.06 in the Control group respectively (P=0.000 in both groups). The positive rates of T-SPOT.TB test in both groups were significantly higher than those of PPD skin test (34.52% (68/197) in the Observation group and 63.50% (127/200) in the Control group; χ ² was 105.66 in the Observation group and 65.40 in the Control group respectively (P=0.000 in both groups)). The positive rates of T-SPOT.TB and PPD skin test in the Observation group were significantly lower than those in the Control group (the former χ ² was 13.50 (P=0.000) and the later χ ² was 33.36 (P=0.000)).Conclusion The positive rate of T-SPOT.TB test in those patients receiving immunosuppressive agents and are complicated with PTB is high. The T-SPOT.TB test, as an auxiliary diagnostic method of PTB, is more valuable than those traditional methods.