Pasteurella

• Gram-negative bacillus with bipolar staining ("safety pin" appearance)
• Grows on chocolate agar but not MacConkey, unlike other Gram-negative bacteria
• Oxidase positive and indole positive
• Includes Pasteurella multocida
• Normal oral flora of many animals, including humans
• Causes skin and soft tissue infections following bites or closed-fist injuries
• May have beta lactamases
• Treatment is typically with penicillin (if susceptible), amoxicillin-clavulanic acid, or a cephalosporin
  • Not reliably susceptible to cloxacillin or cefazolin