Potential Utility of Metagenomic Sequencing for Improving Etiologic Diagnosis of Infective Endocarditis

Abstract

<b>Aim:</b> To explore potential utility of metagenomic sequencing for improving etiologic diagnosis of infective endocarditis (IE) caused by fastidious bacteria. <b>Materials & methods:</b> Plasma and heart valves of two patients, who were diagnosed with IE caused by <i>Bartonella quintana</i> and <i>Propionibacterium</i> species, were sequenced by using Illumina MiSeq and Nanopore MinION. <b>Results:</b> For patient 1, <i>B. quintana</i> was detected in the plasma pool collected 4 days before valvular replacement surgery. For patient 2, <i>Propionibacterium</i> sp. oral taxon 193 was detected in the plasma sample collected on hospital day 1. Nearly complete bacterial genomes (>98%) were retrieved from resected heart valves of both patients, enabling detection of antibiotic resistance-associated features. Real-time sequencing of heart valves identified both pathogens within the first 16 min of sequencing runs. <b>Conclusion:</b> Metagenomic sequencing may be a helpful supplement to IE diagnostic workflow, especially when conventional tests fail to yield a diagnosis.