Propionibacterium acnes prosthetic valve endocarditis with abscess formation: a case report

Area of Science:

• Infectious Diseases
• Cardiology
• Antimicrobial Therapy

Background:

• Propionibacterium acnes endocarditis is rare, with limited treatment data.
• Surgical intervention for abscess formation in P. acnes endocarditis carries high risk.
• Conservative antibiotic therapy is often necessary but lacks evidence-based guidance.

Observation:

• A 29-year-old patient presented with prosthetic valve endocarditis and left ventricular outflow tract abscess due to P. acnes.
• Cardiac surgery was deemed high-risk, leading to a conservative treatment approach.
• The patient received initial intravenous ceftriaxone and rifampin, followed by oral levofloxacin and rifampin.

Findings:

• The patient completed 7 weeks of intravenous therapy and 6 months of oral therapy.
• Post-treatment follow-up over two years showed no clinical signs of infection.
• Laboratory parameters, radiology scans, and blood cultures remained negative, indicating a cure.

Implications:

• This is the first reported case of successful antibiotic-only treatment for P. acnes prosthetic valve endocarditis with abscess.
• A six-month regimen of rifampin and levofloxacin demonstrated efficacy against stationary-phase and adherent bacteria.
• This approach offers a potential alternative for high-risk patients unsuitable for surgery.