Bacterium
Pasteurella multocida
Cat/dog bite coccobacillus, rapid cellulitis
pass-teh-REL-uh mul-TOH-sih-duh
High-yield clue
Rapid cellulitis within hours of a cat or dog bite points to this Gram-negative coccobacillus.
Overview
A fastidious Gram-negative coccobacillus that is normal oral flora of cats and dogs and a classic study cause of rapidly developing cellulitis after animal bites or scratches.
Classification
- Gram-negative
- Coccobacillus
- Pasteurellaceae
- Facultative anaerobe
- Fastidious
Lab & identification clues
- Oxidase positive vocabulary
- Catalase positive concept
- Indole positive vocabulary
- Bipolar staining teaching note
Associations
- Cat and dog bite/scratch transmission vocabulary
- Rapidly progressing cellulitis presentation vocabulary
- Animal oral-flora reservoir framing
Commonly confused with
- Capnocytophaga species
- Bartonella henselae
Frequently asked questions
What is Pasteurella multocida?
A fastidious Gram-negative coccobacillus that is normal oral flora of cats and dogs and a classic study cause of rapidly developing cellulitis after animal bites or scratches.
What is the Gram stain of Pasteurella multocida?
Pasteurella multocida is Gram negative.
What are the lab clues for Pasteurella multocida?
Lab clues for Pasteurella multocida include Oxidase positive vocabulary, Catalase positive concept, Indole positive vocabulary, and Bipolar staining teaching note.
What is Pasteurella multocida commonly confused with?
Pasteurella multocida is commonly confused with Capnocytophaga species and Bartonella henselae.
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.