Eczema is the most common inflammatory skin condition in both children and adults and is one of the chief reasons children visit a dermatologist. Eczema can present in various clinical forms and can be confusing for patients and their nondermatologic healthcare providers. The word eczema was coined by the Ancient Greeks to mean “a boiling out or over” and accurately describes both the microscopic and clinical appearances of acute eczema in which the epidermal keratinocytes are swollen and “boil over” creating epidermal vesicles. Currently, the term eczema is more widely applied to a heterogeneous group of inflammatory skin eruptions that share clinical (pruritus, erythema, and scale) and histologic (spongiosis) hallmarks.

Terminologic confusion may also arise if the word dermatitis—a more generalized, often vague designation that refers to inflammation of skin—is used synonymously with eczema or is coupled with it. In general, it is acceptable to use eczema and dermatitis interchangeably. Eczematous dermatitis, therefore, is somewhat redundant, although some might argue that the term is more inclusive than either word alone.

In this chapter, atopic dermatitis and irritant contact dermatitis, forms of eczema that commonly occur in children, will be discussed. Allergic contact dermatitis, nummular dermatitis (aka nummular eczema) and asteatotic eczema are other forms of eczema more often seen in adults and are discussed in Chapter 13: Eczema and Related Disorders.