Intraoperative diagnosis of mitral valve endocarditis secondary to Paenibacillus provencensis

Area of Science:

• Infectious Diseases
• Microbiology
• Cardiology

Background:

• Infective endocarditis (IE) is a serious infection affecting heart valves, often caused by common bacteria.
• Paenibacillus species are rarely implicated in human infections, with limited data on their pathogenic potential.

Observation:

• A 70-year-old woman presented with a mitral valve vegetation discovered during aortic valve replacement surgery.
• Intraoperative transesophageal echocardiography revealed the unexpected cardiac mass.

Findings:

• Genotypic characterization using 16S rDNA gene sequencing precisely identified Paenibacillus provencensis as the causative pathogen.
• This marks the first documented instance of IE attributed to this specific bacterium.

Implications:

• This case expands the known spectrum of bacterial pathogens capable of causing infective endocarditis.
• Highlights the importance of advanced molecular techniques for accurate pathogen identification in rare infections.
• Suggests that Paenibacillus species should be considered in the differential diagnosis of culture-negative or unusual IE cases.