Atopic dermatitis (Eczema)

Page 1 2 3

What is Atopic dermatitis?

This animation brought to you by Blausen Medical Communications.
Contact Andrew Walbank.

Atopic dermatitis, or eczema, is a chronic skin disease in which the skin becomes red, dry, itchy or scaly and may weep, bleed and crust over. 'Atopic' is a term used to describe allergic conditions for which there is a family history , 'dermatitis' means inflammation of the skin.

Eczema is part of the 'atopic triad' of allergic conditions (also including asthma and hay fever) in which many sufferers experience all three conditions. It is the incessant itch of eczema that separates it from other skin diseases such as psoriasis.

The site of the disease depends on the age of the patient.

In young children, the dermatitis typically occurs on the face, scalp, limbs, or body trunk. The nappy areas are usually spared.
In older children and adolescents, the dermatitis is often accompanied by thickening and darkening of the skin, as well as scarring from repeated scratching. The sites involved are usually the extensor areas, ie the knee and elbow areas.
In adults, the dermatitis most commonly affects the back of the neck, the elbow creases, and the backs of the knees (called the flexural areas). Other affected areas may include the face, wrists, and forearms.

Atopic dermatitis or Eczema and its affect on the skin of the abdomen

Who gets Atopic dermatitis?

Eczema is becoming increasingly common. About 8 to 25% of people worldwide have eczema, compared to 4% in the 1940s. It often occurs in people who have other allergic disorders, such as asthma and hay fever. Eczema may occur at any age, however most often eczema begins in infancy and childhood. Eczema typically manifests in infants aged 1-6 months. Eczema equally affects males and females; however females generally have a worse prognosis.

Predisposing Factors

Eczema is caused by a complex interaction between genes and environmental triggers. Researchers have found that around two-thirds of eczema cases and a quarter of asthma cases involve mutations to a gene that helps form the skin's outer protective layer. This outer layer is made up of dead cells that are collapsed together into a continuous protein sheath that keeps water in and invaders such as bacteria out. Filaggrin is one of the proteins that is very important in maintaining this protective barrier. Several studies have now demonstrated an association between mutations in the filaggrin gene and ezcema.

Environmental triggers that start off eczema have also been identified. Anything that could dry the skin may worsen atopic dermatitis. Potential triggers include:

Skin infections
Emotional stress
Food or preservatives
Pollens and dust mites
Exposure to tobacco smoke
Irritating clothes and chemicals (loose or poorly fitting clothing that constantly rubs the skin or contact with solvents, detergents, deodorants, cosmetics, and soaps)
Excessively hot or cold climate or environment (hot showers or baths, overdressing, use of electric blankets or heating pads, and exposure to high humidity).
Excessive bathing, hand washing, lip licking, sweating, or swimming.

Progression

The predominant symptom is intense itch. In children, sometimes itching can be so intense that the skin breaks after prolonged scratching. In this case sometimes infection leading to pus formation may occur.

Page 1 2 3