DNA探针在呼吸机相关性肺炎病原学检测中的诊断价值

目的建立一种早期、快速检测呼吸机相关性肺炎致病菌的分子生物学方法。方法采用聚合酶链反应合成铜绿假单胞菌、甲氧西林耐药金黄色葡萄球菌、大肠杆菌、肺炎克雷伯杆菌和流感嗜血杆菌这5种细菌的特异DNA探针和细菌16SrRNA的通用探针,分别与生物素标记的细菌、病毒和真菌DNA杂交。杂交法和培养法同时检测100份痰液标本。结果所合成的DNA探针具有高度特异性,与其他细菌、病毒、真菌间无交叉反应。该方法可检测出1 ng细菌DNA。杂交法阳性率显著高于培养法。结论所合成的DNA探针敏感性高,特异性强,具有较高的应用价值,可应用于临床标本检测。

Diagnostic value of DNA probes in the detection of pathogenic bacteria of ventilator-associated pneumonia

Objective To establish a molecular biological method for rapid detecting pathogenic bacteria of ventilator-associated pneumonia.Methods Specific DNA probes of Pseudomonas aeruginosa,methicillin-resistant staphylococcus aureus,escherichia coli,klebsiella pneumoniae, Haemophilus influenzae and 16S rRNA universal probe of bacteria were synthesized by using polymerase chain reaction.The DNA probes were hybridized with the DNA of bacteria,virus and fungi labeled with biotin respectively.Totally 100 sputum specimens were detected with the hybridization and the culture method.Results The synthesized DNA probes were highly specific without cross reaction with other bacteria,viruses or fungi.The method could detect 1ng bacterial DNA.The positive rates of hybridization were higher than those of culture method.Conclusion The synthesized DNA probes is sensitive,specific and with high value and it can be used in clinical specimens examination.