Allergic Inhalant Dermatitis: Introduction
(Atopy) |  |
| Allergic inhalant dermatitis is a common form of allergy in dogs and cats. It is generally accepted to be a Type I (IgE or IgG) hypersensitivity and is believed to affect ~10% of the canine population. Its incidence in cats has not been reported. |
| Etiology and Pathogenesis: |
| Animals with atopy are thought to be genetically programmed to become sensitized to allergens in the environment. Allergens are proteins that, when inhaled or absorbed through the skin, respiratory tract, or GI tract, evoke allergen-specific IgE production. These allergen-specific IgE molecules affix themselves to tissue mast cells or basophils. When they come in contact with the specific allergen, mast cell degranulation results in the release of proteolytic enzymes,
histamine, bradykinins, and other vasoactive amines, leading to inflammation (erythema, edema, and pruritus). The skin is the primary target organ in dogs and cats, but rhinitis and asthma can also occur in ~15% of affected animals. |
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