Review of Staphylococcus pseudintermedius infection in dogs and humans

Abstract

Staphylococcus pseudintermedius is a Gram-positive bacterium and coagulase positive organism commonly found in dogs. It is colonized in over 90% of healthy dogs and is the most common cause of dermatological infection, otitis externa and second most common cause of urinary tract infection. S. pseudintermedius is an opportunistic pathogen and host associated factors may play a big role on pathogenesis of an infection than virulence genes found in its bacterial genome. Number of molecular characterization techniques have been optimized for outbreak investigation, and understanding the bacterial infection and diversity of individual strains in a population would be beneficial to determine the source of infection and control strategies. Pathogenesis has not been fully investigated in S. pseudintermedius although it was extensively investigated in Staphylococcus aureus. Antimicrobial resistance is emerging in S. pseudintermedius and resistance was reported for the common drugs which are used in companion animal medicine. Methicillin resistance emerged in 1990 in Europe and the organism had been reported all over the world. Two epidemic clones of methicillin resistant S. pseudintermedius were identified as ST 71 and ST 68, European and North American epidemic clones, respectively. Multi drug resistance was reported both in methicillin resistant and methicillin susceptible S. pseudintermedius in dogs. S. pseudintermedius causes secondary infection in humans, and is often underreported or misdiagnosed as S. aureus in diagnostic laboratories. The organism is commonly found in dog bite wounds. Immunocompromised patients and people who suffer metabolic diseases are more susceptible for S. pseudintermedius when they have close contact with the canine host.