16S rRNA Metabarcoding Used to Identify the Etiology of Infective Endocarditis Agents

Area of Science:

• Microbiology
• Genetics
• Cardiology

Background:

• Infective endocarditis (IE) is a serious infection affecting heart valves.
• Accurate identification of etiological agents is crucial for effective treatment.
• Current diagnostic methods may have limitations in detecting all causative bacteria.

Purpose of the Study:

• To evaluate the efficacy of 16S rRNA metabarcoding for identifying bacterial pathogens in native cardiac valves from IE patients.
• To compare the performance of 16S rRNA metabarcoding with conventional diagnostic techniques.

Main Methods:

• Analysis of 20 native cardiac valve samples from 16 IE patients.
• DNA extraction and 16S rRNA gene sequencing using Illumina MiSeq platform.
• Bioinformatic analysis to identify bacterial composition.

Main Results:

• The study identified dominant bacterial genera including *Streptococcus*, *Sphingomonas*, *Pseudomonas*, *Roseateles*, *Phyllobacterium*, and *Enterococcus*.
• Opportunistic pathogens like *Ralstonia pickettii*, *Bacillus*, and *Klebsiella* were also detected.
• A high prevalence of diverse bacteria was observed in valves, even in cases with negative blood cultures.

Conclusions:

• 16S rRNA metabarcoding is an effective tool for identifying bacterial agents in infective endocarditis.
• This molecular approach offers advantages over routine noninvasive diagnostic methods for IE.
• Native cardiac valves harbor a complex bacterial community, including opportunistic pathogens, in IE patients.