Steatitis (Yellow Fat Disease) in Cats: A 2025 Veterinary Guide to Causes, Symptoms & Treatment 🐱🟡

By Dr. Duncan Houston, BVSc

Steatitis, also known as yellow fat disease or pansteatitis, is an inflammatory condition affecting the adipose (fat) tissue in cats. Characterized by painful, firm nodules under the skin, this condition can significantly impact a cat's quality of life. This comprehensive 2025 guide delves into the causes, symptoms, diagnosis, treatment, and prevention of steatitis in felines.

Understanding Steatitis in Cats 🧬

Steatitis involves inflammation of the subcutaneous fat tissue, leading to the formation of nodules that may be firm or soft. These nodules can vary in size and may ulcerate, leading to discharge. The condition can be painful and may cause systemic signs if left untreated.

Common Causes

• Dietary Imbalance: Feeding cats a diet high in unsaturated fatty acids, particularly from oily fish like tuna, without adequate vitamin E supplementation can lead to fat oxidation and inflammation.
• Vitamin E Deficiency: Vitamin E acts as an antioxidant, preventing the breakdown of fat. A deficiency can result in fat necrosis and inflammation.
• Infections: Bacterial, fungal, or mycobacterial infections can cause inflammation of the fat tissue.
• Trauma: Physical injuries, such as bite wounds or blunt force, can lead to localized steatitis.
• Pancreatitis or Pancreatic Cancer: Inflammation or neoplasia of the pancreas can extend to surrounding fat tissue.
• Immune-Mediated Diseases: Conditions like lupus panniculitis involve the immune system attacking fat tissue.
• Post-Injection Reactions: Inflammation following subcutaneous injections, including vaccines or medications.
• Neoplastic Diseases: Tumors such as mast cell tumors or lymphosarcoma affecting subcutaneous fat.

Recognizing the Symptoms 🔍

Symptoms of steatitis in cats may include:

• Subcutaneous Nodules: Lumps beneath the skin, often on the trunk, that may be firm or soft.
• Ulceration: Nodules may rupture, leading to discharge of oily or bloody fluid.
• Hair Loss: Alopecia over the affected areas.
• Pain or Discomfort: Especially when the nodules are touched.
• Systemic Signs: Fever, lethargy, or loss of appetite in severe cases.

Diagnosis 🩺

Diagnosing steatitis involves:

• Physical Examination: Assessing the size, location, and characteristics of the nodules.
• Fine Needle Aspiration (FNA): Collecting cells from the nodule for cytological analysis.
• Biopsy: Surgical removal of tissue for histopathological examination to confirm diagnosis and rule out neoplasia.
• Laboratory Tests: Blood work to assess systemic involvement and identify underlying causes.
• Imaging: Radiographs or ultrasounds if internal involvement is suspected.

Treatment Options 💊

Treatment strategies depend on the underlying cause:

• Dietary Changes: Eliminating fish from the diet and providing a balanced, vitamin E-rich diet.
• Vitamin E Supplementation: Administering vitamin E to address deficiencies.
• Antibiotics or Antifungals: To treat bacterial or fungal infections.
• Immunosuppressive Therapy: Corticosteroids or other immunosuppressants for immune-mediated steatitis.
• Supportive Care: Pain management and wound care for ulcerated nodules.
• Surgical Intervention: In cases where nodules are extensive or not responding to medical therapy.

Prognosis 📈

The prognosis for cats with steatitis varies:

• Favorable: When the underlying cause is identified and treated effectively.
• Guarded: In cases with systemic involvement or when the underlying cause is not identified.
• Recurring: Some cats may experience recurrence, especially if the underlying cause persists.

Preventive Measures 🛡️

Preventing steatitis involves:

• Proper Nutrition: Ensuring a balanced diet with adequate vitamin E levels.
• Safe Injection Practices: Using proper techniques and rotating injection sites.
• Prompt Treatment of Infections: Addressing skin infections or wounds promptly to prevent progression.
• Regular Veterinary Check-ups: Early detection and management of underlying conditions.

When to Consult a Veterinarian 👩‍⚕️

Seek veterinary attention if your cat exhibits:

• New or growing lumps under the skin
• Ulcerated or draining nodules
• Signs of pain or discomfort
• Systemic symptoms like fever or lethargy

Conclusion 📝

Steatitis in cats is a multifactorial condition that requires a thorough diagnostic approach to identify the underlying cause. Early detection and appropriate treatment are crucial for a favorable outcome. For personalized advice and support, consider reaching out to veterinary professionals through platforms like Ask A Vet. Their expertise can guide you through diagnosis, treatment options, and ongoing care tailored to your cat's specific needs.

Stay proactive in your cat's health to ensure a happy and healthy life together. 🐾