Psoriasis is a chronic, autoimmune disease that appears on the skin. It occurs when the immune system sends out faulty signals that speed up the growth cycle of skin cells. Psoriasis is not contagious.
There are five types of psoriasis. The most common form, plaque psoriasis, appears as raised, red patches covered with a silvery white buildup of dead skin cells. Psoriasis can occur on any part of the body and is associated with other serious health conditions, such as diabetes, heart disease and depression.
Psoriasis is the most common autoimmune disease in the U.S. As many as 7.5 million Americans have psoriasis.
Scientists believe that at least 10 percent of the general population inherits one or more of the genes that create a predisposition to psoriasis. However, only 2 percent to 3 percent of the population develops the disease. Researchers believe that for a person to develop psoriasis, the individual must have a combination of the genes that cause psoriasis and be exposed to specific external factors known as “triggers”.
Psoriasis triggers are not universal. What may cause one person’s psoriasis to become active, may not affect another. Established psoriasis triggers include:
- Injury to skin
- Although scientifically unproven, some people with psoriasis suspect that allergies, diet and weather trigger their psoriasis. Strep infection is known to trigger guttate psoriasis.
Source: National Psoriasis Foundation