Definition
Psoriatic arthritis (PsA) is a chronic, inflammatory disease of the joints where tendons and ligaments connect to bone. Like psoriasis, PsA is associated with related health conditions (comorbidities).
People of any age (even children) can develop PsA, However, the disease often appears between ages 30 and 50. For many people, it starts about 10 years after psoriasis develops, but some develop PsA first or without ever developing or noticing psoriasis. According to the National Psoriasis Foundation, psoriatic arthritis affects 30% of people with psoriasis.
PsA occurs less frequently in Blacks, however, Blacks have more severe skin involvement.
Symptoms
PsA can develop slowly, with mild symptoms, or it can develop quickly and severely.
Common symptoms of PsA include:
- Fatigue
- Tenderness, pain and swelling over tendons
- Swollen fingers and toes that sometimes resemble sausages
- Stiffness, pain, throbbing, swelling and tenderness in one or more joints
- Reduced range of motion
- Morning stiffness and tiredness
- Nail changes, such as pitting or separation from the nail bed
- Redness and pain of the eye (uveitis)
- There is little connection between psoriasis severity and PsA severity. You could have few skin lesions but many joints affected by arthritis
Causes
Psoriatic arthritis occurs when your body’s immune system attacks healthy cells and tissue. The immune response causes inflammation in your joints as well as overproduction of skin cells.
Both genetic and environmental factors play a role in this immune system response. Several people with psoriatic arthritis have a family history of either psoriasis or psoriatic arthritis.
In addition, physical trauma or a viral or bacterial infection can trigger psoriatic arthritis in people with an inherited tendency.
Risk factors
The following factors can increase your risk of psoriatic arthritis:
- Psoriasis. Having psoriasis is the largest risk factor for developing psoriatic arthritis.
- Family history. A large group of people with psoriatic arthritis have a parent or a sibling with the disease.
- Age. Although anyone can develop psoriatic arthritis, it occurs more frequently in adults between the ages of 30 and 55.
Diagnosis
There is no definitive diagnostic test for PsA, however, your doctor will observe you and use the process of elimination to make a diagnosis. Your doctor will talk with you about your medical history and may perform a physical examination, blood tests, MRI and X-rays.
Though there is no cure, there is a growing range of treatments available to help stop the disease progression, lessen pain, protect joints and preserve range of motion. If you have or suspect you may have PsA, it is extremely important to work with a rheumatologist (a doctor who specializes in how the immune system affects joints, bone and muscles) to find the right treatment plan.
Early recognition, diagnosis and treatment of PsA can prevent or limit the extensive joint damage that can occur in later stages of the disease.
Some people may develop PsA in a joint after an injury. Development may also be related to genetics. Scientists estimate that at least