Cellulitis in Dogs and Cats

1 Symptoms

Cellulitis commonly starts where injections, catheters, or trauma affect the loose tissue under the skin of the thigh, hip, or muscle layers — especially at intravenous sites.

Early on, a diffuse, fluid-like swelling appears that is hot, clearly painful, and firm to the touch. The animal runs a fever, becomes dull, and loses appetite.

As it advances, bacteria and their toxins kill and liquefy tissue, forming an abscess; the skin may break open and drain foul-smelling pus, and whole-body signs ease. Left untreated, cellulitis can cause sepsis and death.

2 Causes and Transmission

Infection by pus-forming bacteria — especially Staphylococcus aureus, hemolytic Streptococcus, and putrefactive organisms — sometimes mixed with other bacteria.

3 Diagnosis

The veterinarian examines the hot, painful, rapidly spreading swelling and checks for fever and whole-body illness; the site is assessed for abscess formation.

4 Treatment

Local care is combined with whole-body antimicrobials to control infection and prevent sepsis.

Early cold packs and veterinary-prescribed anti-inflammatory soaks help; when swelling is severe, the area may be opened in several places and flushed. Formed abscesses are opened and drained. Systemic antimicrobials are chosen by sensitivity.

5 Prevention

Keep injection and wound sites clean; treat small infections early.

Have rapidly spreading, painful swellings examined promptly to avoid sepsis.