Psoriasis is an inherited disorder of the skin, which causes red, scaling bumps and patches on the skin. It is a chronic disorder, which means that the symptoms come and go throughout a person's life.
Psoriasis is an inherited disease that causes an increase in skin cells on the outer layer of the skin. In a healthy individual, skin cells mature and shed from the surface of the body about every 28 days. People with psoriasis shed skin cells every 3 to 4 days. The excess skin cells build up and form the skin lesions of psoriasis.
The exact cause of psoriasis is unknown, but it is commonly believed that the body's immune system triggers the rapid growth and shedding of skin cells. Several genes have been linked to psoriasis, which tends to run in families. However, many people with psoriasis have no family history of the disease.
Certain factors seem to trigger plaque development in people with psoriasis. Suspected triggers include the following:
A person can develop psoriasis at any age. However, it most often develops in two age ranges. The first is between 16 and 22 years of age, and the second is between 57 and 60 years of age. It affects men and women equally and is seen in all races. However, psoriasis is more common in people of Western European and Scandinavian ancestry.
Following are the five major types of psoriasis, each with its own characteristic skin lesions:
Other symptoms of psoriasis are as follows:
The severity of symptoms may range from a mild cosmetic problem to a disfiguring, disabling condition.
A healthcare professional can diagnose psoriasis by doing a medical history and complete physical examination. The characteristic skin lesions will show what type of psoriasis an individual has.
Psoriasis cannot be prevented, but it can be controlled. Certain triggers may be controlled or eliminated to help curb the outbreaks. Take these measures to prevent flare-ups of psoriasis.
Psoriasis can have an emotional, as well as a physical, impact on people. Psoriatic arthritis, a form of joint inflammation that occurs in some people who have arthritis, can be painful and disabling.
Psoriasis is not contagious and poses no risk to others.
An assessment of lifestyle, including stress levels and aggravating factors, should be made. Triggers should be reduced or eliminated.
Gentle removal of scales is important. Oils or coal tar preparations can be added to baths, and a soft brush can be used to scrub lesions carefully. Emollient creams, such as those containing alpha hydroxy acids or salicylic acid, may be used after bathing to soften thick scales. A regular skin routine is important, even when no flare-up of psoriasis is present.
Mild to moderate cases of psoriasis can also be treated with medicines that are applied to the skin, including:
Moderate to severe psoriasis may be treated with phototherapy, or exposure to light, that is carefully prescribed by the healthcare provider. Possible options include:
Severe psoriasis is often treated with the following oral medicines:
Isolated patches of psoriasis that are resistant to other therapy may be injected with triamcinolone acetonide.
Side effects of steroid creams and ointments include thinning of the skin and stretch marks. Coal tar can make the person sensitive to ultraviolet light. Anthralin and vitamin-based products can irritate the skin. Phototherapy increases a person's chance of developing skin cancer or premature aging of the skin. Retinoids can cause birth defects if taken by a pregnant woman. Methotrexate can damage the liver, while cyclosporine can damage the kidneys.
Psoriasis should clear substantially with appropriate treatment, although this varies from person to person. Treatment of psoriasis is lifelong.
Any new or worsening symptoms should be reported to the healthcare provider.
Author:Lynn West, MD
Date Written:
Editor:Crist, Gayle P., MS, BA
Edit Date:09/30/01
Reviewer:Eileen McLaughlin, RN, BSN
Date Reviewed:08/20/01