Understanding Feline Panniculitis: Causes, Signs, and Management
Panniculitis in cats refers to inflammation of the subcutaneous fat tissue. While it's more common in cats than dogs, it's still considered rare overall. The hallmark of this condition is the appearance of firm swellings or nodules beneath the skin, which might become tender and sometimes rupture—releasing yellow to bloody fluid. After rupture, you might notice discoloration of the skin and the formation of scars or crusts. No cat is immune: it can affect any age, sex, or breed.
What Does Feline Panniculitis Look Like?
The most common presentation involves one or more lumps under the skin. These nodules are often found on the trunk or abdomen but can pop up anywhere on your cat's body. Sometimes they're soft; other times, quite firm. They may be freely movable under the skin or firmly attached to deeper tissues. Overlying skin could look normal—or turn red, brown, or yellow.
- Lumps may ulcerate (break open), bleed, or become infected.
- Discharge can range from oily to bloody.
- Ruptured nodules often leave behind scarring and sometimes permanent hair loss.
Systemic symptoms are possible too. As fat tissue breaks down, toxic substances might enter your cat's bloodstream. This can cause fever, lethargy, depression, and loss of appetite—sometimes even before you spot any skin lesions.
What Causes Panniculitis in Cats?
Panniculitis has many potential triggers:
- Trauma: The most common culprit (think bite wounds or injections). A single lump often points to this cause.
- Bacterial or fungal infections: Organisms like Staphylococcus, Pseudomonas, Mycobacterium (including rapidly growing species), Sporothrix, Histoplasma, and Blastomyces can all play a role.
- Immune-mediated diseases: Conditions like lupus panniculitis fall here.
- Cancer (neoplastic diseases)
- Nutritional deficiencies: Especially vitamin E deficiency (historically seen with fish-based diets).
- Pancreatitis
- Poor nutrition
- Drug reactions
- Disease affecting blood supply
If there are multiple lumps rather than just one, your veterinarian will look for underlying diseases beyond simple trauma.
Diagnosing Feline Panniculitis
Your vet will start with a thorough health history and physical exam. To confirm panniculitis and rule out cancerous changes:
- A fine needle aspiration (FNA) or biopsy collects tissue samples for microscopic analysis (cytology and histopathology).
- Blood tests (CBC and biochemistry profile) help assess systemic involvement and check for infections.
- Cultures may identify bacteria or fungi responsible for infection.
- Imaging studies can reveal deeper involvement or associated conditions like pancreatitis.
This careful workup helps distinguish between infectious and non-infectious forms—and guides treatment decisions.
Treatment Options for Cats with Panniculitis
Treatment depends on what's causing the problem:
- If infection is present: Targeted antibiotics or antifungals are prescribed based on culture results. Mycobacterial infections require long courses of specific antibiotics such as doxycycline or clarithromycin; drug selection depends on susceptibility testing.
- Surgical removal: Localized nodules are often excised surgically—especially if they don't respond to medical therapy alone. Perioperative antibiotics help prevent recurrence. Severe cases may need aggressive surgical excision with reconstruction if necessary.
- If no infectious agent is found: Immunosuppressive drugs—most commonly glucocorticoids like prednisolone—are used. Other immune-modulating medications (cyclosporine or tacrolimus) may be added if needed; sometimes tetracycline combined with niacinamide helps when steroids alone aren't enough.
- Nutritional support: Vitamin E supplementation is recommended if deficiency is suspected—though true dietary causes are now rare due to improved commercial diets.
Treating underlying conditions such as pancreatitis or immune disorders is equally important for long-term success. Recurrences do happen—especially when systemic disease or immune dysregulation is involved—so ongoing monitoring matters.
Prognosis and Prevention Tips
The outlook for affected cats is generally good if therapy targets both immediate lesions and any underlying disease process. Identifying—and eliminating—the root cause improves chances of full recovery and reduces recurrence risk.
- Keep cats indoors to minimize trauma risks from fights or accidents.
- Feed a balanced diet; supplement vitamins only under veterinary guidance.
- If your cat needs injections regularly (for chronic illness), ensure proper technique to avoid local reactions.
- Treat injuries promptly; watch for new lumps or unexplained skin changes.
Panniculitis doesn't always have an obvious trigger—and sometimes remains idiopathic (no clear cause). But with attentive care from both owner and veterinarian, most cats respond well to treatment and enjoy a good quality of life afterwards.
