What Causes Necrotizing Granulomatous Steatitis in Dogs?

A sudden lump on your dog could indicate steatitis.
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Necrotizing granulomatous steatitis is a mouthful, but, broken down, necrotizing refers to dying, while granulomatous means inflammation. Steatitis, more often called panniculitis, is inflamed fat. Such a diagnosis means your dog is suffering from dying, inflamed fatty tissue. The cause of necrotizing granulomatous steatitis varies, but it often occurs in canines with other serious diseases.

Canine Steatitis

Technically, panniculitis refers to an inflamed lump occurring in fatty, subcutaneous tissue. Steatitis is a fatty tissue inflammation in any area of the body, and is usually quite painful. While steatitis or panniculitis can affect canines, felines are more likely to suffer from either type of lump. If your dog develops a lump anywhere on his body, take him to the veterinarian promptly for a diagnosis and treatment. It's best to have your pet treated before the tissue starts dying, or necrotizing. The granulomatous inflammation is a reaction to the dying fatty tissue.

Steatitis Symptoms

Besides the tell-tale lump, dogs afflicted with steatitis might experience fever, lethargy, appetite loss, exercise intolerance and obvious pain. As the tissue dies off and ulcerates, the lump might start to drain an oily secretion, with changes in skin color near the area. In canines, the lumps are most often located on the trunk.

Steatitis Causes

Steatitis can result from trauma, infection complications, blood vessel disease, cancer, autoimmune issues and as an inflammatory response. Less often, steatitis results from direct fungal or bacterial infection. If your dog has been diagnosed with pancreatitis or pancreatic or liver cancer, he may end up with this fatty tumor. Radiation therapy can cause steatitis, as can a foreign material in the body. However, many cases of steatitis are idiopathic, meaning there's no conclusive cause. The condition is more common in older dogs.

Dietary Causes

If you feed a quality commercial dog food, it's unlikely your pet will develop steatitis because of his diet. If you feed your dog home-cooked meals, that's another story. A lack of vitamin E or antioxidants can contribute to steatitis development, as can feeding dogs excessive amounts of fish as part of their steady diet. The same holds true for feeding dogs high amounts of pig brains.

Steatitis Treatment

While overall treatment depends on the underlying cause, your veterinarian will likely drain or excise the lump and prescribe steroids to treat inflammation. She might prescribe antibiotics if infection is present. It's likely your dog will retain a scar in the area of the necrotized tissue.