The Staphylococcus intermedius group of bacterial pathogens: species re-classification, pathogenesis and the emergence of meticillin resistance.

Staphylococcus intermedius has been long regarded as the common cause of pyoderma in dogs and other animals. Despite its clinical importance, our understanding of the population genetics and pathogenesis of S. intermedius is limited. This review summarizes recent studies which have explored the genetic diversity of S. intermedius isolates resulting in a re-classification of the species and the identification of Staphylococcus pseudintermedius as the common canine pyoderma pathogen. Also discussed will be the recent identification and spread of meticillin-resistant strains of S. pseudintermedius in the context of their molecular evolution. While our understanding of S. pseudintermedius pathogenesis is very limited, it is hoped that current genome sequencing studies will result in fresh impetus for studies of disease pathogenesis and for the design of novel therapeutic approaches for the treatment of canine pyoderma.