实时荧光核酸恒温扩增检测技术对痰标本中结核分枝杆菌的诊断价值*

目的 评估实时荧光核酸恒温扩增检测（SAT）技术对痰标本中结核分枝杆菌（MTB）的诊断价值。方法 收集确诊为活动性肺结核（PTB）的115例和无证据显示为活动性PTB的67例总计182例患者的痰液标本，采用集菌涂片法、罗氏培养法、PCR荧光探针法及Xpert MTB/RIF法及SAT法进行检测，分析对比检测结果。结果 SAT法检测PTB患者MTB的检出率为40.00%，与罗氏培养法的检出率（40.87%）比较，差异无统计学意义（P?>0.05）。以罗氏培养法为标准，SAT法敏感性、特异性、阳性预测值、阴性预测值、约登指数分别为95.74%（95% CI：0.8975，0.10174），98.53%（95% CI：95.59%，101.46%），0.9783（95% CI：0.9345，0.1022），0.9710（95% CI：0.9304，0.1012）和0.94。其中阳性预测值高于Xpert MTB/RIF法，各指标均优于PCR荧光探针法。ROC曲线结果显示SAT法AUC为0.936。结论 SAT法检测MTB敏感性、特异性和准确度较高，操作简单，检测周期短，其检测结果可以作为临床诊断参考。

Research of real-time fluorescence isothermal RNA amplification assay in detection of mycobacterium tuberculosis in sputum specimens*

Objective To assess the clinical value of real-time fluorescence isothermal RNA amplification assay in the detection of mycobacterium tuberculosis in sputum specimens. Methods Sputum specimens have been collected from 182 patients including 115 PTB patients and 67 patients without evidence of PTB. MTB was detected by using Roche culturing method, PCR fluorescence quantitative expansion method, Xpert MTB/RIF method and SAT method respectively. The test rating for MTB detection was analyzed. Results The positive detection rate of Roche culturing method and SAT method were 40.00% and 40.87% respectively in patients clinically diagnosed as PTB. Two sets of data had no statistically significant differences (P?>?0.05). The sensitivity, specificity, positive predictive value, negative predictive value and Youden index of SAT method for MTB detection were 95.74% (89.75, 101.74), 98.53% (95.59, 101.46), 97.83% (93.45, 102.20), 97.10% (93.04, 101.16) and 0.94 respectively. The positive predictive value of SAT method increased obviously compare with Xpert MTB/RIF method and all test rating were superior to PCR method. AUC of SAT method (0.936) in ROC curve indicated that the method has higher test value of MTB. Conclusion The sensitivity, specificity and accuracy of the SAT method for MTB detection are high, the operation is simple, and the detection cycle is short. It can be used as a reference for clinical diagnosis.