Primary Human Streptococcus canis Bloodstream Infection Linked to Cat Contact: A Case Report and Review of Literature

Streptococcus canis is a rare zoonotic pathogen reported to cause human disease, including skin and soft tissue infections, bloodstream infections, and infective endocarditis. The majority of cases have been linked to contact with dogs, with a paucity of cases related to cats. It is generally susceptible to penicillin and vancomycin but exhibits a high rate of resistance to erythromycin and an inducible resistance to clindamycin.

A man in his sixties presented with fever, chills, and a diabetic foot ulcer that had been exposed to a cat. He was found to have S. canis primary bloodstream infection, which showed a typical susceptibility to beta-lactams and vancomycin, and resistance to clindamycin and macrolides. He was treated with ceftriaxone and had no recurrence at the 3-month follow-up.

S. canis related to cat exposure is an extremely rare cause of human infection, in such cases, a beta-lactam antimicrobial should be initiated. In individuals with an allergy to beta-lactams, vancomycin should be used with avoidance of macrolides and clindamycin as empirical therapy due to the high resistance rate to these antimicrobials among S. canis.