Psoriatic arthritis is a chronic inflammatory disease that affects about 30% of people who already have psoriasis, a chronic skin disease. It occurs when your immune system mistakenly starts attacking healthy joints and skin. The faulty immune response causes inflammation that can trigger joint pain, stiffness and swelling, as well as red, scaly skin patches called plaques.
1 in 3 people with psoriasis may develop psoriatic arthritis.
For some people, symptoms can be mild with occasional flare-ups. For others, they can be continuous. Over time, psoriatic arthritis can cause irreversible joint damage in some patients, so the earlier you receive a diagnosis, the better.
What are the types of psoriatic arthritis?
Identifying where your symptoms are occurring and their severity can help your doctor determine which type of psoriatic arthritis you may have.
- Symmetric psoriatic arthritis is the most common type. It is similar to rheumatoid arthritis in that it affects the same joint on both sides of the body at the same time.
- Asymmetric psoriatic arthritis can occur in any joint but not the same joints on both sides of the body.
- Distal psoriatic arthritis causes inflammation and stiffness near the ends of the fingers and toes. Changes in the nails are common and include pitting, white spots, and lifting from the nail bed.
- Spondylitis is characterized by symptoms of pain and stiffness in the spine and neck.
- Arthritis mutilans, the most severe form, causes deformities in the small joints at the ends of the fingers and toes and affects only 5 percent of people who have it.