实时荧光定量聚合酶链反应在检测大肠埃希菌引起血流感染中的应用

摘要

目的 探讨实时荧光定量聚合酶链反应(FQ-PCR)在检测大肠埃希菌引起血流感染中的应用.方法 从血培养阳性瓶中提取细菌基因组DNA,以大肠埃希菌特异性引物应用实时荧光定量,扩增16S rRNA靶片段,同期进行细菌培养鉴定,对比实验结果.结果 通过对实时FQ-PCR体系特异性、敏感度、稳定性验证,结果表明具有较好的特异性、稳定性,最低检测限为106 copies·L-1,相当于105 CFU·L-1,并且整个实验可在2 h完成.结论 实时FQ-PCR法可直接用于血培养阳性瓶的快速检测,也可用于分离菌株的鉴定,对诊断大肠埃希菌引起血流感染具有较好的应用价值.%Objective To investigate the application of the real-time fluorescent quantitation polymerase chain reaction (FQ-PCR) in the detection of bloodstream infections caused by Escherichia coli. Methods Bacterial genomic DNA was extracted from the hemoculture positive bottles, 16S rRNA target fragments was amplified through real-time FQ-PCR was applied in specific primers,meanwhile,bacterial culture assessment was made and results were compared. Results Through the test of specificity, sensitivity, stability of real-time FQ-PCR, the results showed this method had good specificity and stability, and limit of detection was 106 copies ?L-1,equivalent to 105 CFU?L-1 ,and the whole experiment was completed within 2 hours. Conclusion Real-time FQ-PCR method can be used for the rapid detection of blood culture positive bottles and it can also be used for the identification of abstraction strain,it has great application value for the diagnosis of bloodstream infections caused by Escherichia coli.