T-SPOT中TBAg/PHA比值在结核病诊断中的应用价值

The application of TBAg/PHA ratio in T-SPOT in the diagnosis of tuberculosis

目的探讨结核分枝杆菌特异性抗原(TBAg)/植物凝集素(PHA)比值诊断活动性结核病(ATB)、潜伏性结核病(LTBI)及陈旧性结核病(OTB)的应用价值。方法选取2016年10月至2017年6月该院收治的住院且T细胞斑点试验(T-SPOT)检测均为阳性的结核病患者191例,其中确诊为ATB患者101例,LTBI患者84例,OTB患者6例。采用T-SPOT试验对2种TBAg进行检测,包括早期分泌靶抗原-6(ESAT-6)和培养滤液蛋白-10(CFP-10)。统计ESAT-6、CFP-10和PHA形成的斑点数(sfc),计算ESAT-6/PHA比值和CFP-10/PHA比值,其中比值大者定义为TBAg/PHA比值并纳入统计分析。结果 ATB组患者PHA sfc显著低于LTBI组和OTB组,TBAg/PHA比值显著高于LTBI组和OTB组,差异均有统计学意义(P<0.05);以TBAg/PHA比值为0.279 8作为区分ATB和LTBI的临界值,灵敏度和特异性分别达82.00%和91.67%。结论 TBAg/PHA比值可用于诊断ATB,且在鉴别ATB和LTBI方面具有较好的临床应用价值。

Objective To explore the diagnostic value of mycobacterium tuberculosis specific antigen（TBAg）/phytagglutinin（PHA）ratio in active tuberculosis（ATB）,latent tuberculosis（LTBI）and old tuberculosis（OTB）.Methods 191 tuberculosis patients admitted to our hospital from October 2016 to June 2017 with positive T-SPOT test were selected.Among them,101 patients were diagnosed as ATB,84 patients with LTBI and 6 patients with OTB.Two kinds of TBAg were detected by T-SPOT test,including early secretion target antigen-6（ESAT-6）and culture filtrate protein-10（CFP-10）.Spot counts（sfc）formed by ESAT-6,CFP-10 and PHA were counted.ESAT-6/PHA ratio and CFP-10/PHA ratio were calculated.The larger ratio was defined as TBAg/PHA ratio and included in the statistical analysis.Results In the ATB group,sfc of PHA was decreased significantly comparing to LTBI group and OTB group.The TBAg/PHA ratio in ATB group was significantly higher than that in LTBI and OTB group,and the differences were statistically significant（P<0.05）.The sensitivity and specificity were 82.00%and 91.67%respectively when the TBAg/PHA ratio was 0.279 8 as the critical value to distinguish ATB from LTBI.Conclusion The ratio of TBAg/PHA can be used to diagnose ATB,and has good clinical value in identifying ATB and LTBI.