• Atopic dermatitis (AD), also known as atopic eczema, is a type of inflammation of the skin (dermatitis).
• It results in itchy, red, swollen, and cracked skin.
• Clear fluid may come from the affected areas, which often thicken over time.
• The condition typically starts in childhood with changing severity over the years.
• In children under one year of age much of the body may be affected.
• As people get older, the back of the knees and front of the elbows are the most common areas affected.
• In adults the hands and feet are the most commonly affected areas.
• Scratching worsens symptoms and affected people have an increased risk of skin infections.
• Many people with atopic dermatitis develop hay fever or asthma.
• The cause is unknown but believed to involve genetics, immune system dysfunction, environmental exposures, and difficulties with the permeability of the skin.
• If one identical twin is affected, there is an 85% chance the other also has the condition.
• Those who live in cities and dry climates are more commonly affected. Exposure to certain chemicals or frequent hand washing makes symptoms worse.
• While emotional stress may make the symptoms worse it is not a cause.
• The disorder is not contagious.
• The diagnosis is typically based on the signs and symptoms.
• Other diseases that must be excluded before making a diagnosis include contact dermatitis, psoriasis, and seborrheic dermatitis.

Source: Wikipedia