Alternate Names: Plaque psoriasis
Causes and Risks:
Psoriasis is very common, with approximately 3 million Americans affected (or about 8 out of 10,000 people). It can appear suddenly or gradually. It may affect any age, but it most commonly begins between 15 to 35 years old. It occurs most frequently in Caucasians. Psoriasis is characterized by frequent episodes of recurrences and remissions.
Psoriasis seems to be an inherited disorder, and it appears to be related to the immune or inflammatory response. It is most commonly seen on the trunk, elbows, knees, scalp, skin folds, or fingernails, but it may affect any or all parts of the skin.
Normally, skin takes about a month for its new cells to move from the lower layers of skin up to the surface. In psoriasis, this process takes only a few days, resulting in build-up of dead skin cells and formation of thick scales.
Psoriasis may be aggravated by injury or irritation (cuts, burns, rash, insect bites), and it may be severe in immunosuppressed people (such as with chemotherapy for cancer, or with AIDS), or those who have autoimmune disorders (rheumatoid arthritis).
Medications, viral or bacterial infections, excessive alcohol consumption, obesity, lack of sunlight, overexposure to sunlight (sunburn), stress, general poor health, cold climate, and frequent friction on the skin are also associated with flare-ups of psoriasis. Psoriasis is not contagious.
Prevention: None is known. Minimize flare-ups by avoiding aggravating factors.
Symptoms:
- Skin patches
- Dry or red
- Usually covered with silvery scales
- Raised patches of skin
- Accompanied by red borders
- May crack and become painful
- Usually discrete, demarcated patches
- Usually located on the elbows, knees, trunk, scalp, hands or nails
- Skin lesions, including pustules, cracking of skin, skin redness or inflammation
- Itching
- Small scaling dots on the skin (especially in children)
- Joint pain or aching, which may be associated with a special type of arthritis (psoriatic arthritis)
Additional symptoms that may be associated with this disease:
Signs and Tests: The diagnosis is usually based on the appearance of the skin.
- A skin biopsy or scraping and culture of skin patches may be needed to rule out other disorders.
- A blood test for HLA antigens may be positive.
- An x-ray to check for psoriatic arthritis, if joint pain is present and persistent.
Treatment:
Treatment is focused on control of the symptoms and prevention of secondary infections. It varies with the extent and severity of the disorder.
Severe or resistant cases, or cases involving large areas of the body, may require intensive treatment. Psoriasis lesions that cover all or most of the body are an emergency symptom that require hospitalization. The disorder may be acutely painful.
The body loses vast quantities of fluid and is susceptible to severe secondary infections that can become systemic, involving internal organs, and can progress to septic shock and death. Treatment includes analgesics, sedation, intravenous fluids, and antibiotics.
Mild cases are usually treated at home. Topical medications include:
- Prescription or nonprescription dandruff shampoos
- Shampoos or lotions that contain coal tar
- Cortisone or other corticosteroids
- Lubricants
- Antifungal medications
- Antibiotics
- Phenol
- Sodium chloride
- Other ingredients
Oral or injected immunosuppressive medications (such as corticosteroids or methotrexate) may be prescribed, but only in very severe cases. Other medications may include retinoids or cyclosporine.
Other treatments may include moderate exposure to sunlight or phototherapy. The skin is sensitized by the application of coal tar ointment or by taking oral psoralens (a medication that causes the skin to become sensitive to light). The person is then exposed to ultraviolet light. Avoid sunburn, which can worsen the condition.
Psoriatic arthritis, which occurs in a very small percentage of patients with psoriasis, may be treated with non-steroidal analgesics in much the same way as normal arthritis.
Maintain good general health to reduce the risk of flare-ups. Obtain adequate rest and exercise, eat a well-balanced diet, and avoid stress (see stress management). Treat respiratory and other infections promptly.
Maintain good skin hygiene to prevent secondary infections. Daily baths or showers are recommended. Avoid harsh scrubbing, which can irritate the skin and cause new outbreaks.
Oatmeal baths may be soothing and may help to loosen scales. Commercial preparations may be used, or mix one cup of oatmeal into a tub of warm water.
Support Groups: The stress of illness can often be helped by joining a support group where members share common experiences and problems. See psoriasis - support group.
Prognosis: Psoriasis is a chronic, lifelong condition that can be controlled with treatment. It usually does not adversely affect general health, unless it is neglected or occurs in the elderly or very young.
Complications:
- Skin cancer
- Rapidly aging skin
- Cataracts
- Complications secondary to treatments
- Secondary skin infections which spread to internal organs
Call for an appointment with your health care provider if symptoms indicate psoriasis.
Call for an appointment with your health care provider if psoriasis recurs frequently despite treatment.
Also call if pustules, fever, muscle aches, fatigue, or other new or unexplained symptoms develop.
