交叉引物恒温扩增检测技术在疑似肺结核患者临床诊断中的价值

目的 评估交叉引物恒温扩增(cross priming amplification, CPA)检测技术在肺结核早期临床诊断中的应用价值。 方法 以2016年1—10月广东省佛山市和江门市及所辖7个县(区)级结核病防治机构(简称“结防机构”)就诊的初诊疑似肺结核患者为研究对象,共纳入患者6507例;所有患者均进行了胸部影像学检查并送检痰标本进行涂片镜检、固体培养和CPA检测,培养阳性菌株进行菌种鉴定,项目点临床医生结合实验室和临床检查结果对纳入患者进行初诊诊断,国家级临床专家对初诊临床诊断结果进行现场复核。分析项目地区确诊活动性肺结核患者中病原学阳性患者所占比例,并与专家复核后的临床诊断结果进行比较,分析涂片镜检、固体培养和CPA诊断肺结核的敏感度及特异度。 结果 6507例疑似肺结核患者中,涂片镜检、固体培养和CPA检测阳性率分别为18.2%(1187/6507)、25.0%(1629/6507)和23.9%(1555/6507)。3199例临床确诊为活动性肺结核患者中,涂片联合培养阳性检出率为48.5%(1550/3199),涂片联合CPA阳性检出率为47.9%(1531/3199),涂片、培养和CPA三种方法联合检测阳性率为54.4%(1740/3199)。以临床诊断结果为标准,涂片镜检、固体培养和CPA检测诊断活动性肺结核的敏感度分别为35.0%(1120/3199)、46.4%(1485/3199)和44.6%(1428/3199),特异度分别为98.0%(3241/3308)、95.7%(3164/3308)和96.2%(3181/3308)。 结论 县(区)级结防机构可应用CPA检测技术用于疑似肺结核患者的快速诊断,多种诊断技术联合应用可显著提高活动性肺结核患者的病原学诊断阳性率。

The value of cross priming amplification test in clinical diagnosis of suspected pulmonary tuberculosis patients

Objective To evaluate the application value of cross priming amplification (CPA) test in the early clinical diagnosis of pulmonary tuberculosis (PTB). TB suspected patients who went to the 7 TB dispensaries at county or district level in Foshan and Jiangmen cities of Guangdong province from January 2016 to October 2016 were enrolled, a total of 6507 suspected PTB patients were included. All of the recruited patients completed chest X-ray examination and provided sputum samples to perform smear microscopy, solid culture and CPA test, and species identification were performed for culture positive strains. The clinician made diagnosis combining laboratory and clinical examination results, and clinical experts at national level reviewed the initial clinical diagnosis on-site. The proportion of pathogenic positive patients in active PTB was analyzed. Comparison with reviewed clinical diagnosis results was conducted to analyze the sensitivity and specificity of smear microscopy, solid culture and CPA. The positive rates of smear microscopy, solid culture and CPA were 18.2% (1187/6507), 25.0% (1629/6507) and 23.9% (1555/6507) respectively. Among 3199 clinically diagnosed patients with active PTB, the positive detection rate of smear combined culture was 48.5% (1550/3199), the positive rate of smear combined with CPA was 47.9% (1531/3199), and that of smear combine culture and CPA was 54.4% (1740/3199). Compared with clinical diagnosis results as the standard, the sensitivities of smear microscopy, solid culture and CPA test for TB detection were 35.0% (1120/3199), 46.4% (1485/3199) and 44.6% (1428/3199) respectively, and the specificities were 98.0% (3241/3308), 95.7% (3164/3308) and 96.2% (3181/3308), respectively. TB dispensary at county (district) level can apply CPA test for rapid diagnosis of suspected PTB patients. The combination of multiple diagnostic techniques can significantly increase the pathogen positive rate of active TB patients.