Final answer:
Acute contact dermatitis presents as vesicles and erythema, typically as a result of a type IV hypersensitivity reaction upon exposure to allergens such as poison ivy or nickel.
Step-by-step explanation:
The form of contact dermatitis that presents as vesicles (small blisters) and erythema (redness of the skin) is typically considered acute contact dermatitis. This type of dermatitis represents an inflammatory reaction of the skin resulting from direct exposure to an allergen or irritant. In the context of type IV hypersensitivity reactions, which are cell-mediated immune responses, contact dermatitis can occur after exposure to substances such as poison ivy or nickel.
Acute contact dermatitis is characterized by the rapid onset of skin inflammation following exposure to the allergen. Common symptoms include redness, swelling, and the formation of vesicles. Chronic contact dermatitis, on the other hand, usually involves more persistent skin changes, like thickening and scaling, due to repeated or prolonged exposure to the irritant or allergen.