Understanding Panniculitis in Cats: Causes, Treatment, and Prognosis
Panniculitis is a condition characterized by the inflammation of subcutaneous fat tissue, presenting as firm swellings or nodules that may ulcerate and discharge fluid. While it is more common in cats than in dogs, it remains a relatively rare condition. Proper diagnosis and treatment are essential, as this condition seldom resolves without medical intervention.
Common Causes of Panniculitis
This condition may arise due to various reasons, many of which require targeted treatments. The causes can be classified into two main categories:
- Infectious causes: Includes bacteria (like Staphylococcus or Pseudomonas), fungi (such as Sporothrix), and parasites.
- Non-infectious causes: Include trauma, immune-mediated diseases (e.g., lupus), drug reactions, nutritional deficiencies (especially vitamin E), injections, and pancreatitis.
Trauma is the most common cause, especially when a single lump is found. Multiple lumps may indicate a systemic issue that requires more thorough investigation.
Clinical Signs to Watch For
Owners should be vigilant for the following signs in their pets:
- Firm or soft subcutaneous nodules
- Nodules that are tender, freely movable or fixed under the skin
- Possible ulceration and discharge (yellow, oily, or bloody fluid)
- Changes in skin color and potential scarring
- Systemic symptoms: Lethargy, fever, depression, and appetite loss
These symptoms may precede visible skin lesions or nodules, making early veterinary consultation important.
Diagnostic Approach
Veterinarians follow a multi-step diagnostic process to identify and confirm panniculitis. This includes:
- Detailed health history and physical examination
- Fine needle aspiration (FNA) or biopsy for cytology and histopathology
- Blood tests: CBC and biochemistry profile
- Imaging studies to detect hidden infections or systemic issues
- Culture and sensitivity testing to pinpoint infectious agents
Microscopic analysis is particularly critical to rule out malignancies and guide treatment.
Treatment Options
Treatment depends on the underlying cause:
Infectious Panniculitis
- Antimicrobials: Prescribed based on the identified bacteria or fungi
- Mycobacterial infections: Require prolonged antibiotic courses (e.g., doxycycline, clarithromycin)
- Surgical excision of localized nodules is often necessary
- Perioperative antibiotics help prevent recurrence
Non-Infectious (Sterile) Panniculitis
- Immunosuppressive drugs: Prednisolone is commonly used
- Other options: Cyclosporine, tacrolimus, tetracycline/niacinamide combinations
- Vitamin E supplementation in cases of suspected or confirmed deficiency
In some cases, even when no clear cause is found, patients respond well to immunosuppressive therapies, leading to the designation of “idiopathic sterile nodular panniculitis.”
Long-Term Outlook and Complications
The prognosis is generally good when the underlying cause is appropriately managed. However, complications or recurrences may occur, especially in:
- Immune-mediated or systemic diseases
- Cases with delayed treatment
- Extensive tissue damage requiring surgical reconstruction
Routine monitoring and follow-up appointments are crucial to detect new lesions early or adjust treatment plans accordingly.
Preventive Measures
To reduce the risk of panniculitis in pets:
- Keep cats indoors to avoid trauma and reduce infection risk
- Ensure balanced nutrition, avoiding poorly formulated diets
- Practice proper injection techniques
- Supplement with vitamin E where appropriate
- Act promptly on any signs of injury or skin changes
Owners should closely observe their pets and seek veterinary attention if they notice any suspicious lumps, changes in skin color, or systemic symptoms such as lethargy or inappetence.
Conclusion
Panniculitis is a complex but manageable disease affecting cats of all ages and breeds. Since it rarely resolves on its own, veterinary involvement is crucial for proper diagnosis and successful treatment. By identifying the root causes and administering the appropriate therapies—whether antimicrobial, immunomodulatory, nutritional, or surgical—most cats can recover well. Preventive care and monitoring also play vital roles in maintaining long-term health and reducing disease recurrence.





