Psoriasis

What Is It?

Psoriasis is a chronic (long-lasting) skin disorder that causes scaling and inflammation. Psoriasis is one of the world's most common skin disorders, affecting 2% to 3% of all people. It may develop as a result of an abnormality in the body's immune system, which normally fights infection and allergic reactions. Psoriasis probably involves heredity, because up to 40% of patients have family members with the same problem. Certain medications, such as lithium, a medication for bipolar disorder, may trigger psoriasis. Other medications, including beta-blockers, a class of heart and blood pressure medicines, seem to make psoriasis worse in people who already have the disease.

Symptoms

Psoriasis causes skin scaling and inflammation, with or without itching. There are several types of psoriasis including:

• In plaque psoriasis, rounded or oval patches (plaques) of affected skin usually are red and covered with a silvery scale. The plaques generally grow slowly and occur on the elbows, knees or scalp or near the buttocks.
• Inverse psoriasis is a plaque type of psoriasis, but its surface is usually moist, the opposite of typical psoriasis plaques. It tends to affect skin creases, especially those in the underarm, groin, buttocks or genital areas or under the breast.
• In pustular psoriasis, the skin patches are studded with pimples or pustules.
• In guttate (meaning droplike) psoriasis, many dime-sized or smaller red, scaly patches develop suddenly and simultaneously, often in a young person who has had a strep throat or a viral upper respiratory infection.

About 50% of people with skin symptoms of psoriasis also have abnormal fingernails, especially nail thickening or small indentations, called pitting. Arthritis, called psoriatic arthritis, can affect 10% to 20% of all people with psoriasis, and in some people, it occurs before skin changes appear.

Diagnosis

Your health care professional will look for the typical skin and nail changes of this disorder.

Frequently, your doctor can diagnose psoriasis based on the results of your physical examination. When skin symptoms are not typical of the disorder, your doctor may recommend a skin biopsy to confirm the diagnosis or to rule out other possible skin disorders. In a biopsy, a small sample of skin is removed and examined in a laboratory.

Expected Duration

Psoriasis is a long-term disorder, although symptoms may come and go.

Prevention

There is no way to prevent psoriasis.

Treatment

Treatment for psoriasis varies depending on the type of psoriasis, the amount and location of affected skin, and the risks and benefits of each type of treatment.

• Topical treatments These are treatments applied directly to the skin. They include emollients for lubrication, such as petroleum jelly; corticosteroid drugs, available in high-potency forms for stubborn plaques on the hands or feet and in milder forms for areas of delicate skin; calcipotriol (Dovonex), a synthetic form of vitamin D, which slows production of skin scales; tazarotene (Tazorac), a topical synthetic vitamin A derivative; coal tar; or salicylic acid to remove scales.
• Phototherapy For extensive or widespread psoriasis, light treatment (using ultraviolet B, or UV-B light, similar to what is used in a tanning booth) may be used alone or combined with coal tar. In psoralen ultraviolet light treatment (PUVA), ultraviolet A light is combined with an oral medication called psoralen, which improves the effectiveness of the light treatment. Laser treatment also can be used. It allows treatment of the involved skin to be more focused so that higher amounts of UV light can be used.
• Treatments for moderate to severe psoriasis involving large areas of the body These include vitamin A derivatives acitretin (Soriatane), methotrexate (Folex, Methotrexate LPF, Rheumatrex) and cyclosporine (Neoral, Sandimmune). These treatments are very powerful, and some have the potential to cause severe side effects involving the liver, kidney or blood. Therefore, it's essential to understand the risks and be monitored closely. More rarely, the medications hydroxyurea (Hydrea) and azathioprine (Imuran) are prescribed for severe disease. Among the newest agents for psoriasis that has not responded to other treatments are the "biologics," medicines that act against naturally occurring cells or chemical messengers thought to promote psoriasis. Examples include alefacept (Amevive), etanercept (Enbrel), infliximab (Remicade) and efalizumab (Raptiva). Biologic treatments tend to be quite expensive and must be injected rather than taken as a pill.

When To Call A Professional

If you are unsure whether you have psoriasis, contact your doctor. Also, contact your doctor if you know you have psoriasis and are not doing well with over-the-counter treatment.

Prognosis

For most patients, psoriasis is a long-term condition. Although there is no cure, there are many effective treatments. In some patients, doctors routinely switch treatments every 12 to 24 months to prevent the treatments from losing their effectiveness and to decrease the risk of side effects.

Additional Info

National Psoriasis Foundation

6600 SW 92nd Ave.

Suite 300

Portland, OR 97223-7195

Phone: (503) 244-7404

Toll-Free: (800) 723-9166

Fax: (503) 245-0626

E-Mail: getinfo@psoriasis.org

http://www.psoriasis.org/