Psoriasis

From ArticleWorld

Psoriasis is a non-contagious skin condition that involves raised red, scaly plaques found most commonly on the knees and elbows. Occasionally, the process will be systemic and lead to arthritis, extensive skin involvement and fingernail involvement.

Types

The most common type of psoriasis is called plaque psoriasis. This involves collections of red, scaly patches on the drier areas of the skin. Pustular psoriasis is similar to plaque psoriasis but has non-infectious pustules on the affected areas. Guttate psoriasis is the second most common type of the disease and involves the collection of small teardrop-shaped lesions on the skin.

Psoriatic arthritis involves the coexistence of an immune-mediated arthritis and psoriasis. Inverse psoriasis is a condition where smoother patches of red skin show up in the folds of the skin—exactly the opposite of where one would expect psoriasis to be. The most severe type of psoriasis is called erythrodermic psoriasis, a condition where wide areas of the skin are involved and the skin exfoliates to a degree where the function of the skin is impaired.

Etiology

Psoriasis is an immune-mediated disease and involves an overactivity of the body’s T cells and the triggering of multiple immune responses. Turnover of skin is rapid, resulting in the scaling and thickening of the skin. The disease appears to be triggered by a physical skin injury or to a mental or emotional stress.

Treatment

Treatments for psoriasis include topical medications, the use of light therapy and systemic therapy. Topical treatments include cortisone creams, creams that control the turnover of skin cells, synthetic vitamin A creams, salicylic acid creams (that help the skin peel), and coal tar preparations, which seem to work best when combined with phototherapy.

Phototherapy for psoriasis generally involves exposure to UVB light radiation, the combination of a medication called a psoralen (light sensitizer) plus exposure to UVA radiation and, in some cases, the limited use of X-ray radiation.

Systemic therapy aims at suppressing the body’s overall immune response. Methotrexate is a medication that suppresses the immune system. Other medications related to vitamin A can sometimes be used. Cyclosporine is another medication that suppresses the immune system of the body when taken systemically.