Final answer:
Canine atopic dermatitis (cAD) leads to chronic symptoms like itching, redness, and irritation due to the immune system's hypersensitive reaction to harmless environmental allergens. This inflammation can also result in secondary infections and skin damage. Hypersensitivity includes immediate reactions like allergic asthma and delayed responses such as contact dermatitis or autoimmunity.
Step-by-step explanation:
The consequences of inflammation in Canine atopic dermatitis (cAD), which is a type of hypersensitivity reaction, include symptoms such as itching, redness, and skin irritation. This chronic inflammatory disease is caused by an inappropriate immune reaction to environmental allergens that are generally harmless. The inflammation arises from the complex interplay between genetic and environmental factors leading to a disrupted skin barrier and immune dysregulation. Due to recurring and persistent inflammation, affected dogs may develop secondary skin infections, increased pigmentation, and thickening of the skin.
Hypersensitivity reactions are excessive immune responses to allergens and can be immediate, like in allergic asthma, or delayed, as in contact dermatitis. In immediate hypersensitivity or Type 1, allergen-specific IgE binds to mast cells causing degranulation and rapid symptoms such as nasal edema and runny nose. Delayed hypersensitivity, on the other hand, involves a cell-mediated immune response and can lead to contact dermatitis, with skin symptoms appearing one to two days after exposure. In the case of autoimmunity, the individual's immune system mistakenly attacks its own body, such as in rheumatoid arthritis or multiple sclerosis.