Which type of dermatitis is caused by contact with an allergen?

• A. Atopic dermatitis
• B. Allergic contact dermatitis
• C. Seborrheic dermatitis
• D. Perioral dermatitis

Answer: (B)

Allergic contact dermatitis is characterized by an inflammatory skin reaction that occurs when the skin comes into contact with a specific allergen. This type of dermatitis results from an immune response triggered by the allergen, leading to symptoms such as redness, itching, and swelling at the site of contact. This response is often delayed, typically appearing within 24 to 48 hours after exposure.

In contrast, atopic dermatitis is primarily associated with genetic predisposition and environmental factors, and it does not result directly from contact with a specific allergen. Seborrheic dermatitis is related to sebaceous gland activity and may be influenced by factors such as yeast overgrowth, while perioral dermatitis often develops around the mouth and may be associated with the use of topical corticosteroids or other cosmetic products rather than a contact allergen.

Thus, allergic contact dermatitis specifically involves an immune response to allergens, making it the correct choice for this question.