Irritant contact dermatitis. Clues to causes, clinical characteristics, and control.

Skin irritation can cause poorly defined nonimmunologic cutaneous changes that may cause diagnostic confusion. Clinical signs include vesicles, papules, bullae, erythema, edema, scaling, and lichenification. In some patients, this condition, termed irritant contact dermatitis, is indistinguishable from endogenous, dyshidrotic, nummular, and atopic dermatitis. Irritant contact dermatitis has only a few typical characteristics. The diagnosis is generally based on clinical appearance, history and, when indicated, diagnostic patch testing to rule out an allergic component. Elimination of the offending agent and protection from further exposure are important in both diagnosis and management. The dermatitis usually heals once the irritant is eliminated, and reexposure should be minimized for weeks to months, if not permanently.