Diagnostic approach in allergic and irritant contact dermatitis.

Contact dermatitis is a highly frequent disease with a significant impact on the quality of life of the affected patients and a relevant socioeconomic impact. According to the pathophysiological mechanisms involved, two major types of contact dermatitis may be recognized: irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). The two types may, and often do, coexist.