NExt-Generation Sequencing and Cell Culture-based Characterization of S. Aureus in Infective Endocarditis

Infective endocarditis is a deadly disease with a mortality rate between 20 and 40%. Antibiotic therapy is of utmost importance. It is primarily guided by microbial results from positive blood culture. However, culture-based microbiological diagnostic can identify the species, but not the strain or the genotypic characteristics of a pathogen. Identifying the strain can be of utmost clinical significance. S. aureus is the most common causative organism of IE worldwide (16%-32%). This pathogen causes massive valve destruction and abscesses, which is strongly dependent on the expression of virulence factors that vary between different S. aureus strains. Functional characterization of S. aureus and determination of virulence factors can currently be achieved through cell culture-based assays (CCBA). However, these tests are very time consuming and cannot be performed as routine clinical diagnostics. Next Generation Sequencing (NSG) has the potential to identify the genotypic characteristics of the pathogen, which is important to determine its virulent potential. The aim of this study is to evaluate the possible utilization of NGS in the prediction of virulence factors of S. aureus and to compare it to the virulence factors determined using CCBA. Hopefully, by comparing the NGS and CCBA, the investigators will get a faster way of determining the possible virulence factors. The NGS method can be further utilized to describe the prevalence of different strains of bacteria in infected valve tissue and blood culture samples. The collected data will serve as a basis for further evaluation of the potentials of NGS-based Diagnosis of IE, as well as a comparison between NGS-guided antibiotic treatment and the standard of care antibiotic treatment.