Establishing a canine superficial pyoderma model

• Published in: Journal of applied microbiology Vol. 122; no. 2; pp. 331 - 337
• Main Authors: Bäumer, W., Bizikova, P., Jacob, M., Linder, K.E.
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-02-2017
• Subjects: Animals; Antimicrobial agents; canine; Dermatitis, Atopic - complications; Dermatitis, Atopic - veterinary; Disease Models, Animal; Dog Diseases - microbiology; Dog Diseases - pathology; Dogs; Female; infection; Male; Microbiology; pulsed‐field gel electrophoresis; pyoderma; Pyoderma - microbiology; Pyoderma - pathology; Pyoderma - veterinary; Staphylococcal Skin Infections - microbiology; Staphylococcal Skin Infections - pathology; Staphylococcal Skin Infections - veterinary; Staphylococcus; Staphylococcus - classification; Staphylococcus - isolation & purification; Staphylococcus - physiology; Staphylococcus infections; Staphylococcus pseudintermedius; veterinary; Staphylococcus pseudintermedius; infection; canine; pulsed-field gel electrophoresis; veterinary; pyoderma
• ISSN: 1364-5072; 1365-2672
• DOI: 10.1111/jam.13362

Aims
Pyoderma, predominantly associated with Staphylococcus pseudintermedius, is a common skin infection of dogs that typically requires long‐lasting treatments, complicated by increasing antimicrobial resistance. To investigate new treatment strategies, we aimed at establishing a dog model of pyoderma that closely mimics the natural disease.
Methods and Results
We inoculated six laboratory beagles with a methicillin‐susceptible strain of S. pseudintermedius. One millilitre of approximately 107, 108, 109 CFU per ml was topically applied onto clipped and tape stripped area of dog skin, which was then treated with a dermaroller (microneedle size: 500 μm) immediately after administration. Dogs were monitored daily, suspect pustules were cultured for S. pseudintermedius and evaluated by cytological and histopathological methods. After 24 h, all dogs developed papules and pustules at all three bacterial inoculation sites, which worsened over the next 48 h. Cytological samples of all skin lesions revealed neutrophils with intracellular cocci. Histopathology confirmed subcorneal neutrophilic pustular dermatitis with intralesional cocci and acantholytic keratinocytes, consistent with superficial pyoderma. Staphylococcus pseudintermedius was isolated from pustules of all dogs and confirmed to be the inoculating strain. The results were replicated in all dogs after a wash out period of 6 weeks.
Conclusions
These data demonstrate the feasibility of establishing a dog model of pyoderma.
Significance and Impact of the Study
The new model can be used to evaluate novel prevention and treatment options for canine pyoderma.