It is partly an allergic response to a range of different protein based allergens. These allergens are found in the environment and, as dust, danders or pollens, may contact the skin, or be inhaled or ingested. As atopic, but presenting in coin shaped patches usually on the limbs and torso. There is no known cause for discoid eczema. As atopic, usually presenting as persistent dandruff, but can spread to the face and skin folds.
Seborrhoeic eczema is a reaction caused by a microbe pityrosporum ovale living on the skin.
As atopic, presenting on the lower legs. Varicose eczema generally occurs in elderly people, being due to poor venous blood circulation. It can be a painful and disabling condition particularly on the hands. If the condition is related to occupation, a change of career is often necessary. Allergic contact dermatitis is caused by an immunological response to an immunological response to an allergen in contact with the skin.