Isolation of methicillin-resistant Staphylococcus aureus from a postoperative wound infection in a horse.

Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from a postoperative wound infection in a horse. Methicillin-resistant S aureus infections in animals have been reported. In human beings, MRSA is an important cause of hospital-acquired (nosocomial) infections. Infections caused by MRSA respond poorly to beta-lactam treatment, and resistance of MRSA to multiple antimicrobials, including aminoglycosides, macrolides, clindamycin, and tetracyclines, is common. Identification of MRSA by routine susceptibility testing may be difficult; therefore, techniques for MRSA detection should be incorporated by clinicopathology laboratories. Because the number of hospital and community-acquired MRSA infections in human beings is increasing, it seems likely that MRSA infections in animals will also become more frequent.