Eosinophilic Granuloma Complex (EGC) is a cat skin condition characterized by a group of skin lesions. Eosinophils are white blood cells that are part of the allergic response. When the cat's body comes into contact with an allergen, these busy little cells are sent to the area to try and fight the allergen. In EGC, eosinophils are like lingering house-guests in that they continue to stay in the area and eventually cause problems long after the allergen is gone. Cats being cats will usually over-groom the area, and the constant licking will exacerbate inflammation. Allergens can be anything including but not restricted to flea saliva, various foods, grasses and pollens. Essentially, EGC is an extreme form of an allergy.
There are three main types of lesions associated with EGC:
Eosinophilic Granulomas- These are red, raised hairless skin lesions that can occur anywhere, but are seen most frequently in the hindquarters. They can be single or in groups, and are very itchy for the cat.
Eosinophilic Plaque- These are raised, ulcerated, hardened lesions that are seen usually on the underside or inner thigh.
Eosinophilic Ulcer- Also called indolent or rodent ulcer, these are ugly little crater-like lesions that are seen anywhere in the mouth. The lips and tongue are common spots for these ulcers. They can be quite painful and can affect the cat's appetite.
Cats with EGC should always be on an effective flea control, in case flea allergy plays a part. Low allergy diets can also be trialled and may help in prevention in the long term. In many cases, the allergen at fault is never identified, but treatment must be administered to reduce irritation and minimize the lesions. Steroids are often the mainstay of treatment, and in some cats, long term steroid may be required. Antibiotics may be prescribed to address any secondary infections. Essential fatty acids may also help reduce future flare-ups.
Did your cat ever have EGC? How did you treat it? Tell us about it in the comments!