What Is Psoriasis?
Psoriasis is a common, chronic, genetic, systemic inflammatory disease that is characterized by symptoms and signs such as elevated itchy plaques of raised red skin covered with thick silvery scales. Psoriasis is usually found on the elbows, knees, and scalp but can often affect the legs, trunk, and nails. Psoriasis may be found on any part of the skin.
The symptoms of psoriasis vary depending on the type you have. Some common symptoms for plaque psoriasis — the most common variety of the condition — include:
- Plaques of red skin, often covered with loose, silver-colored scales; these lesions may be itchy and painful, and they sometimes crack and bleed. In severe cases, the plaques of irritated skin will grow and merge into one another, covering large areas.
- Disorders of the fingernails and toenails, including discoloration and pitting of the nails; the nails may also begin to crumble or detach from the nail bed.
- Plaques of scales or crust on the scalp
Psoriasis can also be associated with psoriatic arthritis, which leads to pain and swelling in the joints. The National Psoriasis Foundation estimates that between 10% to 30% of people with psoriasis also have psoriatic arthritis.