BACKGROUND: Capnocytophaga canimorsus is a bacterium of the normal oral flora of 
dogs and cats. Human infection is caused by animal bite but is rarely observed, 
mainly in immunocompromised patients. We present 2 cases of C. canimorsus 
infection that occurred in immunocompetent patients and caused multiorgan 
failure and in both cases severe neurologic involvement.
CASE REPORT: In the first case, we present a 69-year-old immunocompetent woman 
with septic shock derived from skin and soft tissue infection after a dog's 
bite. She developed ischemic necrosis evolving to gangrene of both forefeet and 
hands, infective aortic endocarditis, and neurologic involvement caused by large 
hemispheric hypodense lesions compatible with ischemic septical lesions. In the 
second case, we present a 65-year-old immunocompetent man with meningitis after 
a dog's bite. Despite antibiotic therapy, he developed neurologic clinical 
deterioration, with right sensitive hemisyndrome associated with lack of 
strength and motor skills of the right hand. Radiologic findings were consistent 
with the diagnosis of cerebritis. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF 
THIS?: Clinicians should always be aware of this pathogen, both in 
immunocompromised and immunocompetent patients, and consider prophylactic 
antibiotics after exposure.