CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, Limoges, France.
Diagn Microbiol Infect Dis. 2013 Mar;75(3):240-4. doi: 10.1016/j.diagmicrobio.2012.11.013. Epub 2013 Jan 12.
Positive heart valve (HV) culture is a major Duke's criterion for the diagnosis of infective endocarditis but is poorly sensitive. Two broad-range 16S rDNA polymerase chain reaction (PCR) methods were applied to 31 HV samples: first, a real-time method, then conventional end-point PCR was applied to HV samples on which the first PCR was negative. Five specific real-time PCR procedures were also used in order to identify Bartonella spp., Tropheryma whipplei, Chlamydophila pneumoniae, Mycoplasma pneumonia, and Coxiella burnetii. A strategy combining the 2-step broad-range PCR methods improved the sensitivity of the molecular method from 38.7% to 58%. Specific PCR identified 1 T. whipplei, which was also identified by conventional end-point PCR. These results confirm that blood culture is the gold standard for the diagnosis of infective endocarditis, shows that molecular methods applied to HV can be useful when blood culture is negative, and that 2-step broad-range PCR approach seems to be more sensitive.
心脏瓣膜（HV）的阳性培养是诊断感染性心内膜炎的主要杜克标准，但敏感性较差。两种广谱 16S rDNA 聚合酶链反应（PCR）方法应用于 31 个 HV 样本：首先是实时方法，然后将第一次 PCR 为阴性的 HV 样本应用于常规终点 PCR。还使用了五种特定的实时 PCR 程序，以鉴定巴尔通体属、Tropheryma whipplei、肺炎衣原体、肺炎支原体和伯氏考克斯氏体。两步广谱 PCR 方法的结合策略将分子方法的灵敏度从 38.7%提高到 58%。特定的 PCR 鉴定出 1 株 T. whipplei，这也被常规终点 PCR 鉴定出来。这些结果证实血培养是诊断感染性心内膜炎的金标准，表明当血培养为阴性时，应用于 HV 的分子方法可能是有用的，并且两步广谱 PCR 方法似乎更敏感。
