Definition of Eczema

湿疹(皮炎)is a particular type of inflammatory reaction of the skin in which there iserythema(reddening), edema (swelling),papules(bumps), and crusting of the skin followed, finally, bylichenification(thickening) andscalingof the skin.Eczemacharacteristically causes itching and burning of the skin.

Atopiceczema, which is also called atopic dermatitis, is a very common skin problem. It may start in infancy, later inchildhood, or in adulthood. Once it gets underway, it tends not to go quickly away.

There are numerous types of eczema:

• Atopic dermatitis-- a chronic skin disease characterized by itchy, inflamed skin
• Irritantcontact eczema-- a localized reaction that includes redness, itching, and burning where the skin has come into contact with an irritant such as an acid, a cleaning agent, or other chemical
• Allergic contact eczema-- a red, itchy, weepy reaction where the skin has come into contact with a substance that theimmune systemrecognizes as foreign, such as poison ivy or certain preservatives in creams and lotions
• Seborrheic eczema-- a form of skin inflammation of unknown cause that presents as yellowish, oily, scaly areas of skin on thescalp, face, and occasionally other parts of the body
• Nummular eczema -- coin-shaped areas of irritated skin most commonly on the arms, back, buttocks, and lower legs that may be crusted, scaling, and extremely itchy
• Neurodermatitis-- scaly patches of skin on the head, lower legs, wrists, or forearms caused by a localized itch (such as an insect bite) that becomes intensely irritated when scratched
• Stasis dermatitis-- a skin irritation on the lower legs, generally related tocirculatoryproblems
• Dyshidrotic eczema-- irritation of the skin on the palms of hands and soles of thefeet特点是清晰的,深blisters that itch and burn.