Picture of Psoriatic Arthritis
Psoriatic arthritis is a type of arthritis that affects both the joints and the skin. It is an autoimmune disease. The immune system creates antibodies that attack certain tissues in the body. Some cases of psoriatic arthritis occur without accompanying skin psoriasis. Arthritis may develop many months or years before or after psoriasis is present.
Text Reference: American College of Rheumatology: "Psoriatic Arthritis"