Staphylococcus species can be isolated from the skin of both healthy cats and those with skin disease. The most commonly isolated organisms are S intermedius, S aureus, S schleiferi, and S hyicus. In addition, methicillin-resistant (MR) staphylococci have been isolated from cats; however, little is known about the prevalence of MR staphylococci in cats. In this study, 5 anatomic sites (nares, mouth, anus, groin, forehead) were cultured from 50 healthy cats with no history of skin disease and from 48 cats with any type of inflammatory skin disease. Coagulase-positive staphylococci and S schleiferi were isolated from 50% of cats with inflammatory skin disease and from 34% of normal cats. Significantly more S aureus isolates were found in cats with inflammatory skin disease than in healthy cats; however, there was no significant difference in the total number of isolates between the 2 groups. MR staphylococci isolation from either group was rare; 5 MR staphylococci isolates were identified in this study, and 5 sites were represented.

COMMENTARY: The major take-home points from this article are that MR staphylococci are uncommon in cats, there is no "one best site" as all 5 cultured positive, and overgrowth of normal bacterial flora complicates inflammatory skin diseases in cats, as in dogs. Indications for culture of the skin are similar: skin lesions that do not respond to therapy should be cultured. Reference laboratories should do speciation because of the potential for infection with coagulase-negative S schleiferi subspecies schleiferi. Reverse zoonotic infections are a concern with any MR staphylococci infection.

Surveillance of healthy cats and cats with inflammatory skin disease for colonization of the skin by methicillin resistant coagulase-positive staphylococci and Staphylococcus schleiferi spp. schleiferi. Abrahan JL, Morris KO, Griffeth GC, et al. Vet Dermatol 18: 252-259, 2007.