Division of Clinical Microbiology, Mayo Clinicgrid.66875.3a, Rochester, Minnesota, USA.
Department of Intensive Care, University Hospital of Guadeloupe, Pointe-à-Pitre, France.
J Clin Microbiol. 2022 Sep 21;60(9):e0062122. doi: 10.1128/jcm.00621-22. Epub 2022 Aug 30.
Initial microbiologic diagnosis of infective endocarditis (IE) relies on blood cultures and and Coxiella burnetii serology. Small case series and one prospective study have preliminarily reported application of metagenomic sequencing on blood or plasma for IE diagnosis. Here, results of a prospective pilot study evaluating targeted metagenomic sequencing (tMGS) for blood-based early pathogen detection and identification in IE are reported. Subjects diagnosed with possible or definite IE at a single institution were prospectively enrolled with informed consent from October 2020 to July 2021. Blood was drawn and separated into whole blood and plasma. Both specimen types were subjected to nucleic acid extraction and PCR targeting the V1-V3 region of the 16S ribosomal RNA gene, followed by next-generation sequencing on an Illumina MiSeqTM platform. 35 subjects, 28 (80%) with definite and 7 (20%) with possible IE were enrolled, including 6 (17%) with blood culture-negative endocarditis (BCNE). Overall, 20 whole blood (59%) and 16 plasma (47%) samples tested positive ( = 0.47). When results of whole blood and plasma testing were combined, a positive tMGS result was found in 23 subjects (66%). tMGS identified a potential pathogen in 5 of 6 culture-negative IE cases. Although further study is needed, the results of this pilot study suggest that blood-based tMGS may provide pathogen identification in subjects with IE, including in culture-negative cases.
感染性心内膜炎（IE）的初始微生物学诊断依赖于血培养和柯克斯体血清学检查。一些小病例系列和一项前瞻性研究初步报道了应用宏基因组测序对血液或血浆进行 IE 诊断。本文报告了一项前瞻性试点研究的结果，该研究评估了靶向宏基因组测序（tMGS）在 IE 中用于早期病原体检测和鉴定的应用。从 2020 年 10 月至 2021 年 7 月，在一家机构中诊断为可能或确诊的 IE 患者在知情同意的情况下前瞻性入组。采集血液并分离为全血和血浆。两种标本类型均进行核酸提取和靶向 16S 核糖体 RNA 基因 V1-V3 区的 PCR，然后在 Illumina MiSeqTM 平台上进行下一代测序。共纳入 35 例患者，28 例（80%）为确诊，7 例（20%）为可能的 IE，其中 6 例（17%）为血培养阴性心内膜炎（BCNE）。总体而言，20 份全血（59%）和 16 份血浆（47%）样本检测为阳性（ = 0.47）。当合并全血和血浆检测结果时，23 例（66%）患者的 tMGS 结果为阳性。tMGS 在 6 例血培养阴性 IE 病例中鉴定出了潜在病原体。尽管还需要进一步研究，但该试点研究的结果表明，基于血液的 tMGS 可能为 IE 患者，包括血培养阴性的患者提供病原体鉴定。
