Definition Psoriasis (sore-eye-i-sis) is an inherited disorder of the skin, causing red, scaling patches usually on the scalp, elbows, forearms, knees and lower back. The fingernails, palms, and soles of the feet can also be involved.
What is going on in the body? Psoriasis is a disease that causes an increase in skin cells on the outer layer of the skin. The cause is unknown. A percentage of cases are inherited.
What are the signs and symptoms of the disease? Signs and symptoms of psoriasis include:
Thick red, itchy plaques found over the body but more commonly on the scalp, in the groin and axilla and the buttock
Thickening of the fingernails and toe nails
Cracking and blistering of the palms and soles of the feet
What are the causes and risks of the disease? Genetic factors play a role in some cases of psoriasis. People with psoriasis may develop psoriatic arthritis that affects fingers and toes. Rapid onset of widespread psoriasis with overlying blisters happens very rarely.
What can be done to prevent the disease? This disease cannot be prevented but it can be controlled. Certain triggers may be controlled or eliminated to help curb the outbreaks. Scratching, rubbing, sunburn, or excessive dryness of the skin can lead to flare-ups of psoriasis. Infections can also cause psoriasis to worsen. Stress can be a large factor in psoriasis. Certain drugs can cause flare-ups of existing psoriasis.
How is the disease diagnosed? Psoriasis is diagnosed through examination by a doctor.
What are the long-term effects of the disease? Psoriasis can have an emotional impact on people as well as a physical impact, especially when it occurs on the palms and soles of the feet or when it occurs with psoriatic arthritis.
What are the risks to others? Psoriasis is not a contagious disease, and does not pose any risk to others.
What are the treatments for the disease? Treatments may include:
topical corticosteroids such as hydrocortisone, betamethasone, or beclomethasone and momentasone.
water-filled dressings that seal the area from air
injection of cortisone into the affected skin area in small amounts. Generally, systemic steroids are not advised.
anthralin
vitamin D analog calcipotriol
methotrexate
cyclosporine
azathioprine
ultraviolet B light therapy
systemic retinoids such as acitretin
What are the side effects of the treatments? Side effects can vary, depending on which treatment is chosen.
What happens after treatment for the disease? Psoriasis should clear substantially with appropriate treatment, although this varies from person to person. Recurrence of psoriasis is likely.
How is the disease monitored? This is dependent on the treatment.
Author: Lynn West, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request