Prolonged Bacteroides pyogenes infection in a patient with multiple lung abscesses

Area of Science:

• Microbiology
• Infectious Diseases
• Pulmonology

Background:

• Bacteroides pyogenes resides in the oral microbiome of cats and dogs.
• Animal bites represent a significant risk factor for human infections by B. pyogenes.
• B. pyogenes infections are known for their persistence despite antibiotic therapy and potential for severe clinical outcomes.

Observation:

• A 55-year-old male presented with a 3-month history of productive cough, night sweats, and weight loss.
• Initial chest radiography revealed mass-like opacities in the right upper lobe, right middle lobe, and left lower lobe.
• The patient underwent extensive investigations and antimicrobial treatments over four years for complex lung abscesses.

Findings:

• The case details a novel presentation of complex lung abscesses caused by B. pyogenes.
• Resolution of the lung abscesses was achieved after a prolonged treatment course.
• Combination therapy with metronidazole and moxifloxacin is believed to be crucial for the clinical cure.

Implications:

• This case underscores the potential for B. pyogenes to cause severe pulmonary infections in humans.
• Effective treatment strategies for B. pyogenes lung abscesses may involve specific antibiotic combinations.
• Understanding the pathogenic potential of B. pyogenes from animal oral microbiomes is critical for public health.