What Are the Causes of Eczema?
Doctors do not know the exact cause of eczema, but a defect of the skin that impairs its function as a barrier, possibly combined with an abnormal function of the immune system, is believed to be an important factor. Asthma, hay fever, and eczema often occur in the same families. Studies have shown that in people with atopic dermatitis there are gene defects that lead to abnormalities in certain proteins (such as filaggrin) that are important in maintaining the barrier of normal skin.
Eczema can be triggered by substances that come in contact with the skin, such as soaps, cosmetics, clothing, detergents, jewelry, or sweat. Environmental allergens (substances that cause allergic reactions) may also cause outbreaks of eczema. Changes in temperature or humidity, or even psychological stress, can lead to outbreaks of eczema in some people.