Introduction

• May be life-endangering dermatoses.
• Cause: predisposed by demodicosis, hypothyroidism, hyperadrenocorticism Hyperadrenocorticism, trauma or immunosuppression, eg neoplasia or internal disease, may be idiopathic (especially German Shepherd pyoderma).
• Signs: papules, pustules, furuncles, discharging sinuses; bacterial infection of dermal and subcuticular tissues.
• Diagnosis: history, clinical signs, microscopy, histopathology, bacteriology.
• Treatment: antimicrobial/antibiotic therapy.
• Prognosis: varied according to bacterial infection.

Pathogenesis

Predisposing factors

General

Generalized deep pyoderma

• Demodicosis Skin: demodectic mange.
• Hypothyroidism Hypothyroidism.
• Idiopathic.
• Other causes of immunosuppression, eg neoplasia, hyperadrenocorticism Hyperadrenocorticism.

Interdigital pyoderma

• Demodicosis.
• Foreign body.
• Hypersensitivity Skin: food hypersensitivity Skin: atopy Skin: pododermatitis and furunculosis.
• Hypothyroidism Hypothyroidism.
• Dermatophytosis Skin: dermatophytosis.

Muzzle and chin pyoderma

• Idiopathic Skin: canine 'acne'.
• Demodicosis.

Pressure point pyoderma

• Poor bedding Skin: decubital ulcers.
• Obesity.
• Hypothyroidism Hypothyroidism.

Anal furunculosis

• Idiopathic Perianal fistula.
• Genetic, anatomical or immunological factors.

Nasal pyoderma

• Idiopathic.
• May not be a form of pyoderma.

Pathophysiology

• Superficial pyoderma → deeper into follicles → rupture of follicular wall → pyogranulomatous perifolliculitis or furunculosis in dermis and subcutis → extension along tissue planes → fistulae on surface or cellulitis and panniculitis in subcutaneous and fatty tissues.
• Combined infection and foreign body reactions.
• Anatomic predisposition - short-coated breeds, eg bull dogs are at higher risk for interdigital pyoderma.

Diagnosis

Treatment

Prevention

Outcomes