Eikenella corrodens

Background

Microbiology

• Facultatively anaerobic, oxidase-positive fastidious Gram-negative bacillus in the genus Eikenella
• Do not grow well on MacConkey agar
• Primary human pathogen within its genus
• Member of the HACEK group of fastidious causes of infective endocarditis
• Member of normal human mouth flora

Clinical Manifestations

• Associated with soft tissue infections after clenched fist injuries involving the human mouth
• Can also caused head and neck infections, pneumonia, lung abscess
• Can cause infective endocarditis

Management

• Often present in polymicrobial infections
• Often susceptible to penicillins, but there is a risk of beta lactamases
• Empiric treatment for severe infections includes ceftriaxone, ampicillin-sulbactam, and piperacillin-tazobactam
  • Oral amoxicillin-clavulanic acid is another option
• Often resistant to clindamycin, metronidazole, and aminoglycosides
• For infective endocarditis: 4 weeks of IV ceftriaxone