Infective endocarditis associated with Bartonella henselae: A case series

Area of Science:

• Infectious Diseases
• Cardiology
• Microbiology

Background:

• Organisms in the genus *Bartonella* are a significant cause of infective endocarditis, particularly cases that are culture-negative.
• *Bartonella* infective endocarditis (BIE) is increasingly recognized worldwide, yet data from Japan remains limited.
• Prompt diagnosis and treatment of BIE are crucial for patient outcomes.

Purpose of the Study:

• To report five cases of infective endocarditis caused by *Bartonella henselae* in Japan.
• To highlight the association between BIE and contact with cats or fleas.
• To emphasize the importance of considering *Bartonella* infection in cases of culture-negative endocarditis.

Main Methods:

• Retrospective case series analysis.
• Review of clinical data, diagnostic workup, and treatment of five patients with BIE.
• Epidemiological investigation focusing on potential sources of infection, such as animal contact.

Main Results:

• Five patients were diagnosed with infective endocarditis associated with *Bartonella henselae*.
• All five patients reported a history of contact with cats or fleas, suggesting a common transmission route.
• The diagnosis was facilitated by considering the epidemiological link to animal exposure.

Conclusions:

• *Bartonella henselae* is an important cause of infective endocarditis in Japan, even in culture-negative cases.
• A history of cat or flea contact is a critical clue for diagnosing *Bartonella* endocarditis.
• Increased awareness and diagnostic consideration of *Bartonella* are necessary for managing infective endocarditis, especially in regions with limited reports.