contact

Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to the chemical or physical agents. Some symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, and swelling. The rash is not contagious or life-threatening, but it can be very uncomfortable.
Contact dermatitis results from either exposure to allergens (allergic contact dermatitis) or irritants (irritant contact dermatitis). Allergic contact dermatitis involves a delayed type of hypersensitivity and previous exposure to allergen to produce a reaction. Irritant contact dermatitis is the most common type and representing for the 80% of all contact dermatitis cases. It is caused by prolonged exposure to irritants leading to direct injury to the epidermal cells of the skin that activate innate immunity system which result in inflammatory cutaneous reaction. Phototoxic dermatitis occurs when the allergen or irritant is activated by sunlight. Diagnosis of allergic contact dermatitis can often be supported by patch testing.

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