Definition:
Eczema is a skin condition characterized by dry, red, and itchy patches on the skin. Eczema is associated with asthma and allergy, though allergy rarely plays a role in development or severity of eczema. Eczema usually begins during infancy, typically on the face, scalp, neck, extensor sides of the forearms, and legs. Up to one in five infants develops eczema, but in more than half of them, the condition improves or disappears completely before they are 15 years old.
If eczema persists into adulthood, it usually affects the face and the skin inside the knees and elbows. There is no cure for eczema but it can be controlled by avoiding anything that makes its symptoms worse. These triggers include irritants such as wool, strong soaps, perfumes, and dry environments. A good skin-care routine and frequent moisturizing can also help to keep eczema under control, but in many cases, corticosteroid creams and ointments may be necessary to reduce inflammation. Eczema tends to run in families. This suggests that eczema is caused by genetic factors as well as by environmental factors.
Source: Hans Bisgaard et al. Danish Paediatric Asthma Centre, Copenhagen, Denmark. PLos Medicine. 2008-06-24
Genetics:
Atopic eczema is a complex disease caused by a mainly unknown interaction between genetic and environmental factors. The genetic component of the disease has been demonstrated in twin studies, and several studies have emphasized the association of atopy in the mother with the development of atopic eczema in the child whereas the evidence for association to an atopic father has been somewhat weaker. In the last years, however, other studies have concluded that the association with both paternal as well as maternal atopy is important in the development of allergic disease in the offspring. Several candidate genes linked to the development of eczema have been identified.
Source: Marit Saunes et al. Norwegian University of Science and Technology, Trondheim, Norway BMC Dermatology 2011-05-20
Risk factors (environmental):
Some global associations which could be explored by further research were weak positive associations between the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema in populations and GNP (Gross National Product per capita), trans fatty acids, paracetamol, and women smoking and inverse weak associations between food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking, and some showed mixed effects (antibiotics and climatic factors).
Source: The International Study of Asthma and Allergies in
Childhood (ISAAC). Asher et al. Respiratory Research. 2010