Understanding Cellulitis in Dogs
Cellulitis is a bacterial skin infection that can affect dogs. Unlike a surface-level skin infection, cellulitis impacts the deeper dermal layers under the skin. If not treated promptly, it can rapidly spread and cause serious complications. While any dog can develop cellulitis, those with allergies, skin folds, or trauma to the skin are most at risk.
What Causes Cellulitis in Dogs?
Cellulitis occurs when bacteria enters the skin through an opening or break and spreads to the deeper tissues. Common causes include:
- A wound, scratch, or ulcer on the skin that forms a portal for bacteria
- Trapped moisture and bacteria in skin folds or wrinkles
- An untreated, superficial skin infection that penetrates more deeply like superficial bacterial folliculitis or surface pyoderma
- Spreading of infection from an abscess, infected anal gland, or infected bone
- An underlying skin condition like allergies or autoimmune disease
- Bacteria entering through sites of medical equipment like an IV or catheter
Bacteria That Cause Cellulitis
While numerous bacteria can lead to cellulitis, the most common include:
- Streptococcus
- Staphylococcus
- Pasteurella
Dogs often develop cellulitis through normal bacteria that lives on their skin or from bacteria in their mouths that enters through a bite wound.
Areas of the Body Commonly Affected by Cellulitis
In dogs, cellulitis frequently develops in areas prone to cuts, abrasions, or excessive moisture. The legs and paws are most commonly affected. Other problem areas include:
- Face and muzzle
- Neck
- Chest and underside
- Tail and anus
- Ears
Identifying Cellulitis in Dogs
Cellulitis Symptoms
Cellulitis can emerge and spread rapidly, so pet owners should watch for these key signs:
- Swollen area of skin - swelling and inflammation develops as fluids and pus collect deep in the tissues
- Skin redness - the area reddens as blood vessels dilate and inflammation develops
- Hot to the touch - inflamed areas often feel warm or hot to the touch though some forms can be cool to the touch
- Pain and tenderness - dogs usually experience discomfort, tenderness, and pain if the swollen area is touched
- Weeping sores or crusts - drainage, pus, or serum may seep from ruptured vesicles in the skin
- Hair loss - hair loss and skin damage often occurs
- Fatigue and fever - lethargy and fever can develop if infection spreads to the bloodstream
Differences from Surface Skin Infections
Unlike some mild surface-level skin infections, cellulitis in dogs impacts deeper tissues under the skin. Signs to distinguish it include:
- More extensive swelling, reddening, pain, and tenderness
- Lumps or hard plaques from inflammation in deeper tissues
- More extensive tissue damage
- Development of oozing blisters and ulcers in the skin
- High fevers from spread to the bloodstream
Diagnosing Cellulitis
To diagnose cellulitis, vets will:
- Take the dog's health history and examine the skin
- Evaluate potential prior causes like wounds, abscesses, or skin infections
- Review any medications or health conditions
- Collect samples by swabbing the area or using needle aspiration to identify bacteria
- Conduct blood tests and urinalysis if infection seems widespread
Differential Diagnoses
Cellulitis must be differentiated from other conditions causing similar skin inflammation including:
- Allergic reaction or contact dermatitis
- Bruising from trauma
- Inflammation triggered by immune disorders
- Inherited swelling disorders
- Swelling from lymph node leaks
Treating Cellulitis in Dogs
Quick treatment is vital to halt cellulitis' rapid progression. Approach consists of:
Antibiotics
Antibiotics given orally, through injection, or intravenously combat the underlying bacteria. Vets choose antibiotics according to bacteria cultured and sensitivities. Commonly prescribed antibiotics for dog cellulitis include:
- Penicillins like penicillin G or amoxicillin
- Cephalosporins like cefpodoxime or cefovecin
- Tetracyclines like doxycycline
- Aminoglycosides for urgent cases
- Topical antibiotics like mupirocin ointments for mild cases
Antibiotics may be needed for 3 to 6 weeks. Urine or blood cell count monitoring helps identify any kidney issues or drops in white blood cell counts.
Wound Care
Proper cleaning and care for wounds, ulcers or oozing blisters on the skin provide symptomatic relief and prevent reinfection. Vets may provide special antiseptic rinses and recommend warm compresses to encourage drainage and healing.
Anti-Inflammatory Medication
Steroids, NSAIDs, or other non-steroidal anti-inflammatory drugs (NSAIDs) treat discomfort, swelling, itching and fluid accumulation. They help resolve inflammatory reactions to bacteria toxins in tissues.
Pain Management
Prescription analgesics treat cellulitis pain in the skin, allowing dogs to heal, rest and eat. Tramadol or fentanyl patches effectively manage pain levels.
Supportive Treatments
Severe cellulitis requires hospitalization for intravenous antibiotics, fluids and electrolytes. In milder cases, topical creams aid healing after other symptoms resolve.
Recovery and Follow-Up Care
Activity Restriction
Resting, restricting activity, and use of an Elizabethan collar prevents re-injury during the healing process. Bandage wraps or splints also protect affected limbs.
Follow up Exams
Vets recheck dogs around 10 to 14 days later to confirm cellulitis resolution, then examine healing progress every 5 to 7 days. Blood tests may recheck white blood cell counts.
Completing the Full Antibiotic Course
Stopping antibiotics too soon before bacteria is totally eliminated lets surviving bacteria regain a foothold. Be diligent about completing the entire prescribed antibiotic course, usually lasting 3 to 6 weeks.
Monitoring for Recurrence
Dogs who develop cellulitis once have a higher risk of recurrence. Preventing reinfection involves keeping the skin healthy, promptly treating wounds, and managing underlying conditions. Report any skin redness, swelling or pain to the vet.
Preventing Cellulitis in Dogs
Cellulitis prevention aims to inhibit bacteria invasion and skin infection. Useful prevention tips include:
- Bathing dogs regularly using antimicrobial shampoos to reduce bacteria on the skin
- Treating any wounds, hot spots, rashes or skin infections promptly
- Keeping skin folds clean and dry to prevent moisture accumulation
- Using collars and harnesses that minimize rubs or skin irritation
- Controlling underlying illnesses like diabetes, hypothyroidism or Cushing's
- Caring for nails, ears and teeth optimally to prevent scratches or bites
- Letting dogs exercise daily to strengthen skin immunity
While diligent skin care reduces risks, cellulitis often arises unexpectedly. Catching cellulitis early and starting antibiotics swiftly is key to effective treatment.