Dissemination of the gene encoding exfoliative toxin of Staphylococcus intermedius among strains isolated from dogs during routine microbiological diagnostics

Phenotypic properties and species-specific PCR tests based on the nuc gene of Staphylococcus intermedius and S. aureus, and a conserved region of 16S rDNA were used to identify 45 S. intermedius and four S. aureus isolated from samples of dogs during routine diagnostics. Four S. pseudintermedius strains used for control purposes reacted positively with the S. intermedius nuc PCR showing the close relationship between both species. Investigating the 45 S. intermedius and four S. pseudintermedius strains for the prevalence of the exfoliative toxin SIET encoding gene yielded the presence of the gene for 21 of the S. intermedius and two of the S. pseudintermedius strains. Partial sequencing of the toxin gene of a single S. intermedius strain and comparing this sequence with that obtained from GenBank revealed an almost complete identity. The presence of the exfoliative toxin gene could mainly be found among S. intermedius isolated from skin and wound infections and from otitis externa possibly indicating a role of this toxin for the clinical symptoms.