A skin hypersensitivity due to hereditary influences. The term eczema comprises a number of pathogenetically different conditions (listed below), all with the histologic hallmark of intercellular edema of the epidermis (spongiosis).

• Atopic eczema (Atopic dermatitis)
• Adult seborrhoeic eczema
• Infantile seborrhoeic eczema
• Allergic contact dermatitis
• Irritant contact dermatitis