Table 1.

Primary conditions and other factors affecting canine pododermatitis.

	Examples
Primary causes
Allergic disease	Canine atopic dermatitis, cutaneous adverse food reaction, contact hypersensitivity
Foreign body	Endogenous (hair, keratin) or exogenous (sharp objects; vegetation including grass awns, splinters)
Endocrine disease	Hypothyroidism, hyperadrenocorticism
Parasites	Demodex, hookworm
Bacterial and fungal infections	Mycobacteria, dermatophytosis, blastomycosis, fungal mycetoma, sporotrichosis
Viral and protozoal infections	Canine papillomatosis, leishmaniasis, canine distemper
Autoimmune and immune-mediated diseases	Pemphigus foliaceus; erythema multiforme; cutaneous vasculitis (drugs, vaccines, infection); symmetric lupoid onychodystrophy; systemic lupus erythematosus
Neoplasia	Squamous cell carcinoma, melanoma, mast cell tumor, keratoacanthoma, inverted papilloma
Other	Trauma; musculoskeletal disease (arthritis, soft tissue injury); idiopathic sterile granuloma; immunomodulatory-responsive pododermatitis; footpad hyperkeratosis; superficial necrolytic dermatitis
Predisposing factors
Hair coat	Short hair coat, matted hair
Body weight	Obesity, large-breed dogs
Altered weight-bearing	Body conformation, osteoarthritis, limb deformity, cruciate disease
Perpetuating factors
Chronic lesion formation and pedal inflammation	Hyperkeratosis, lichenification, fibrosis, scarring, pseudopad formation, deep tissue pockets, ingrown hairs, sinus tracts
Persistent infection	Superficial or deep, including bacterial, fungal, mixed
Secondary factors
Bacterial infection	Staphylococcus, Streptococcus, E. coli, Pseudomonas, Corynebacterium, Enterococcus, other
Fungal infection	Malassezia