Which statement about peristomal allergic dermatitis is NOT true?

• A. It presents with erythema and itching.
• B. Margins may correspond to the shape of the offending surface.
• C. Vesicles or papules may crust and ooze.
• D. It causes immediate swelling that resolves within hours.

Answer: (D)

Peristomal allergic dermatitis is a contact-type inflammatory skin reaction to substances in ostomy products, such as adhesives or barrier materials. The key feature is a delayed hypersensitivity response, so symptoms typically develop hours after exposure and persist until the offending product is removed and the skin can heal. The skin commonly shows erythema and itching, and vesicles or papules may crust and ooze as the inflammation evolves. The margins often mirror the shape of the offending surface because the reaction is confined to where contact occurred. Immediate swelling that resolves within hours is not characteristic of this condition; that pattern fits acute irritant contact reactions or other non-allergic processes, whereas allergic dermatitis tends to develop after exposure and resolve only with removal of the allergen and appropriate treatment.