Microbiology
Gram-negative coccobacillus, includes P. canis, P. dagmatis (sounds like something an ornery Walter Brennan would say), P. multocida ssp. multocida, P. multocida ssp. septica, P. stomatis and a bunch of others.
Epidemiologic Risks
Found in dogs (20%) and cats (50%) mouths as well as pigs, rats, buffaloes and other animals. Really. Check out zoonosis for the skinny.
Increasing incidence in the elderly who have companion animals (PubMed).
Syndromes
Infection usually starts within 24 hours of a bite, it most commonly causes a bite infection. However, given the fact that people let their pets lick them anywhere, you can find the organisms anywhere. I had a case of meningitis in a patient whose cat liked to lick her nose and she put tuna on the nose to encourage the cat. Ick.
CAPD peritonitis (PubMed). I had a case in a patient whose cat liked to sleep in her bag warmer.
And many foot infections in patients who walk about barefoot in a house full of vermin, er, I mean cats.
A case of UTI in an old man who got if from the dog. How I do not know.
Treatment
Penicillin G OR ampicillin OR amoxicillin OR third-generation cephalosporins OR tetracycline OR quinolone.
Avoid: first and second-generation cephalosporins, macrolides.
Notes
Have a low threshold of involving a hand surgeon if a bite. Unless, of course, the infection is not on the hand.
It is named after Louis Pasteur, who first identified it as the cause of chicken cholera. His name is immortalized as chicken shit? Some honor.
It caused the mass die-off (about 200,000) of Saiga Antelopes in Kazakhstan(Pubmed).
Curious Cases
Relevant links to my Medscape blog
Last Update: 06/01/19.