An immune disorder causing skin cell build up, forming scales and dry patches
Psoriasis is a chronic, recurring disease that is identified by one or more raised, thick, pink to red, itchy patches that have silvery scales with a distinct border between the patch and normal skin. The rash can appear anywhere but is usually on the scalp, elbows, knees, lower back and genitals. Occasionally, it can also affect the fingernails. The rash can heal and come back and usually develops in early adulthood. Psoriasis can itch, burn, or sting but is not contagious and cannot spread from person to person.
The cause of psoriasis is unknown, however, research has shown that the disease is hereditary. Psoriasis is the development of new skin cells before the old skin cells can shed from the body. Normally, skin cells are replaced every 28 to 30 days, however with psoriasis; new cells grow and move to the surface of the skin every 3 to 4 days. This build-up of new skin cells pushing against the old skin cells is the cause of the hallmark silvery scales of psoriasis.
Psoriasis can be identified by one or more small patches on the scalp, elbows, knees, back, buttocks. However, it also affects the eyebrows, underarms, navel, the skin around the anus, the cleft where the buttocks meet the lower back, and nails. Initially, patches may clear up after a few months or remain. These smaller patches can grow together to form larger patches. Thick patches or patches on the palms of the hands, soles of the feet, or skinfolds of the genitals are more likely to itch or hurt. Often times the symptoms diminish during the summer when the skin is exposed to bright sunlight.
There are many therapeutics available to treat psoriasis and, often times, it involves a combination of multiple treatment types such as phototherapy, topical drugs, systemic drugs, as well as immunosuppressives, TNF's, and other biologic drugs.