title: Characterization of meticillin-resistant and meticillin-susceptible isolates of Staphylococcus pseudintermedius from cases of canine pyoderma in Australia.
abstract: Meticillin-resistant Staphylococcus pseudintermedius (MRSP) has recently emerged as a worldwide cause of canine pyoderma. In this study, we characterized 22 S. pseudintermedius isolates cultured from 19 dogs with pyoderma that attended a veterinary dermatology referral clinic in Australia in 2011 and 2012. Twelve isolates were identified as MRSP by mecA real-time PCR and phenotypic resistance to oxacillin. In addition to β-lactam resistance, MRSP isolates were resistant to erythromycin (91.6 %), gentamicin (83.3 %), ciprofloxacin (83.3 %), chloramphenicol (75 %), clindamycin (66 %), oxytetracycline (66 %) and tetracycline (50 %), as shown by disc-diffusion susceptibility testing. Meticillin-susceptible S. pseudintermedius isolates only showed resistance to penicillin/ampicillin (90 %) and tetracycline (10 %). PFGE using the SmaI restriction enzyme was unable to type nine of the 12 MRSP isolates. However the nine isolates provided the same PFGE pulsotype using the Cfr91 restriction enzyme. Application of the mec-associated direct repeat unit (dru) typing method identified the nine SmaI PFGE-untypable isolates as dt11cb, a dru type that has only previously been associated with MRSP sequence type (ST)45 isolates that possess a unique SCCmec element. The dt11cb isolates shared a similar multidrug-resistant antibiogram phenotype profile, whereas the other MRSP isolates, dt11a, dt11af (dt11a-associated) and dt10h, were resistant to fewer antibiotic classes and had distinct PFGE profiles. This is the first report of MRSP causing pyoderma in dogs from Australia. The rapid intercontinental emergence and spread of multidrug-resistant MRSP strains confirms the urgent need for new treatment modalities for recurrent canine pyoderma in veterinary practice.
authors.affiliation: Animal Dermatology Clinic - Perth, Murdoch Veterinary Hospital, School of Veterinary and Biomedical Science, Murdoch University, Murdoch, WA, Australia.
authors.forename: Meng
authors.initials: M
authors.lastname: Siak
authors.affiliation: Animal Dermatology Clinic - Perth, Murdoch Veterinary Hospital, School of Veterinary and Biomedical Science, Murdoch University, Murdoch, WA, Australia.
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Burrows
authors.affiliation: Department of Microbiology and Infectious Diseases, PathWest Laboratory Medicine - WA, Royal Perth Hospital, Wellington Street, Perth, WA, Australia.|Australian Collaborating Centre for Enterococcus and Staphylococcus Species (ACCESS) Typing and Research, School of Biomedical Sciences, Curtin University, Perth, WA, Australia.
authors.forename: Geoffrey W
authors.initials: GW
authors.lastname: Coombs
authors.affiliation: School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, SA, Australia.
authors.forename: Manouchehr
authors.initials: M
authors.lastname: Khazandi
authors.affiliation: School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, SA, Australia.
authors.forename: Sam
authors.initials: S
authors.lastname: Abraham
authors.affiliation: Faculty of Veterinary Science, University of Sydney, Sydney, NSW, Australia.
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Norris
authors.affiliation: Department of Pathobiology and Centre for Public Health and Zoonoses, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: J Scott
authors.initials: JS
authors.lastname: Weese
authors.affiliation: School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, SA, Australia.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Trott
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001315:Australia; D001426:Bacterial Proteins / Q000235:genetics; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005838:Genotype; D008297:Male; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D011711:Pyoderma / Q000382:microbiology / Q000662:veterinary*; D013210:Staphylococcus / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C548250:MecA protein, Staphylococcus pseudintermedius