Psoriatic arthritis is an inflammatory arthritis associated with psoriasis, a chronic skin and nail disease that causes a scaly, itchy skin rash as well as pitting, or indentations, on the finger and toe nails. Psoriatic arthritis causes pain and swelling in joints, especially in the fingers and toes. People with psoriatic arthritis may experience either the skin or joint symptoms first, or both symptoms may occur simultaneously. Psoriatic arthritis affects at least 10 percent of the three million people with psoriasis in the United States. It affects men and women equally and usually begins between 30 to 50 years of age, but also can occur in childhood. The exact cause of psoriatic arthritis is unknown. However, genetic and environmental factors may play a role in the development of this disease.
The joint pain associated with psoriatic arthritis often causes stiffness, especially in the morning. About a third of people with psoriatic arthritis also experience neck or back pain and stiffness. Although the severity and range of symptoms of psoriatic arthritis can vary in each person, common symptoms include:
Your doctor will begin by recording your complete medical history and asking you to describe your symptoms. Then you will undergo a physical examination, during which your doctor will look for any physical signs of the disease. The following tests also may be recommended to help make a definite diagnosis:
Erythrocyte Sedimentation Rate: This is a common blood test that is used to detect and monitor inflammation in the body.
Rheumatoid Factor: This blood test detects an antibody that is present in the blood of most patients with rheumatoid arthritis. It is conducted to exclude rheumatoid arthritis.
Arthrocentesis: This is an office procedure during which a sterile needle is used to withdraw fluid from the inflamed joints. The fluid is then analyzed for infection, gout crystals and other inflammatory conditions.
X-rays: These may show characteristic changes associated with arthritis in the spine, sacrum, and joints of the extremities.
Drug Therapy: Nonsteroidal anti-inflammatory drugs (NSAIDs), are initially used for the treatment of psoriatic arthritis. If progressive inflammation or joint destruction occurs despite treatment with NSAIDs, stronger medications such as methotrexate, corticosteroids and anti-TNF (tumor necrosis factor) medications may be recommended.
Injections: Corticosteroid injections directly into the joints can be effective in some cases of psoriatic arthritis.
Exercise: Exercise is an essential element of treatment for psoriatic arthritis. An exercise program can be done at home or with a physical therapist. Physical activity helps to strengthen, maintain and improve joint range of motion. For best results, exercise should be done on a regular basis.
Reviewed by health care specialists at UCSF Medical Center.