程军
OBJECTIVES:Identification of the underlying pathogens of infective endocarditis (IE) is critical for precision therapy.METHODS:We evaluated a metagenomic method with next-generation sequencing (NGS) for the direct detection of pathogens from the resected valves of 44 IE patients and seven rejected IE patients according to the modified Duke criteria.RESULTS:NGS displayed sensitivity, specificity, positive predictive values and negative predictive values of 97.6%, 85.7%, 97.6%, and 85.7% compared with 46.2%, 100%, 100%, and 12.5% for blood culture and 17.1%, 100%, 100%, and 17.1% for valve culture and 51.4%, 100%, 100%, and 26.1% for valve Gram staining, respectively.CONCLUSIONS:NGS technique had superior sensitivity and shorter turnaround time compared with culture-based methods for identifying causative pathogens of IE. The NGS technology should be considered an essential supplement to culture-based methods, particularly for unculturable or difficult-to-culture microorganisms.
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases 2019
BACKGROUND:Pathogens identification is critical for the proper diagnosis and precise treatment of infective endocarditis (IE). Although blood and valve cultures are the gold standard for IE pathogens detection, many cases are culture-negative, especially in patients who had received long-term antibiotic treatment, and precise diagnosis has therefore become a major challenge in the clinic. Metagenomic sequencing can provide both information on the pathogenic strain and the antibiotic susceptibility profile of patient samples without culturing, offering a powerful method to deal with culture-negative cases.METHODS:To assess the feasibility of a metagenomic approach to detect the causative pathogens in resected valves from IE patients, we employed both next-generation sequencing and Oxford Nanopore Technologies MinION nanopore sequencing for pathogens and antimicrobial resistance detection in seven culture-negative IE patients. Using our in-house developed bioinformatics pipeline, we analyzed the sequencing results generated from both platforms for the direct identification of pathogens from the resected valves of seven clinically culture-negative IE patients according to the modified Duke criteria.RESULTS:Our results showed both metagenomics methods can be applied for the causative pathogen detection in all IE samples. Moreover, we were able to simultaneously characterize respective antimicrobial resistance features.CONCLUSION:Metagenomic methods for IE detection can provide clinicians with valuable information to diagnose and treat IE patients after valve replacement surgery. However, more efforts should be made to optimize protocols for sample processing, sequencing and bioinformatics analysis.
Annals of clinical microbiology and antimicrobials 2018
