font size

Psoriatic Arthritis (cont.)

Medical Author:
Medical Editor:

What causes psoriatic arthritis?

The cause of psoriatic arthritis is currently unknown. A combination of genetic, immune, and environmental factors is likely involved. In patients with psoriatic arthritis who have arthritis of the spine, a gene marker named HLA-B27 is found in about 50% of cases. Blood testing is available to test for the HLA-B27 gene. Several other genes have also been found to be more common in patients with psoriatic arthritis. Certain changes in the immune system may also be important in the development of psoriatic arthritis. For example, the decline in the number of immune cells called helper T cells in people with AIDS (HIV infection) may play a role in the development and progression of psoriasis in these patients. The importance of infectious agents and other environmental factors in the cause of psoriatic arthritis is being investigated by researchers.

What are risk factors for developing psoriatic arthritis?

The major risk factor for developing psoriatic arthritis is having a family member with psoriasis. This relationship has been recognized as so significant that it is used as a helpful part of the history for the doctor to diagnose psoriatic arthritis. It might be that stressful life situations could affect the immune system, allowing for the expression and/or exacerbation of psoriatic arthritis. However, precisely how these emotional issues are related to psoriatic arthritis has not been established.

What are psoriatic arthritis symptoms and signs?

In most patients, the psoriasis precedes the arthritis by months to years. The type of psoriatic arthritis depends on the distribution of the joints affected. Accordingly, there are five types of psoriatic arthritis: symmetrical, asymmetric and few joints, spondylitis, distal interphalangeal joints, and arthritis mutilans.

The arthritis frequently involves the knees, ankles, and joints in the feet. Usually, only a few joints are inflamed at a time. The inflamed joints become stiff, painful, swollen, hot, and red. Sometimes, joint inflammation in the fingers or toes can cause swelling of the entire digit, giving them the appearance of a "sausage." Joint stiffness is common and is typically worse early in the morning. Less commonly, psoriatic arthritis may involve many joints of the body in a symmetrical fashion, mimicking the pattern seen in rheumatoid arthritis. Psoriatic arthritis can also cause inflammation of the spine (spondylitis) and the sacrum, causing pain and stiffness in the low back, buttocks, neck, and upper back. Occasionally, psoriatic arthritis involves the small joints at the ends of the fingers. A very destructive, though less common, form of arthritis called "mutilans" can cause rapid damage to the joints. Fortunately, this form of arthritis is rare in patients with psoriatic arthritis.

Patients with psoriatic arthritis can also develop inflammation of the tendons (tendinitis) and around cartilage. Inflammation of the tendon behind the heel causes Achilles tendinitis, leading to pain with walking and climbing stairs. Inflammation of the chest wall and of the cartilage that links the ribs to the breastbone (sternum) can cause chest pain, as seen in costochondritis.

Aside from arthritis and spondylitis, psoriatic arthritis can cause inflammation in other organs, such as the eyes, lungs, and aorta. Inflammation in the colored portion of the eye (iris) causes iritis, a painful condition that can be aggravated by bright light as the iris opens and closes the opening of the pupil. Corticosteroids injected directly into the eyes are sometimes necessary to decrease inflammation and prevent blindness. Inflammation in and around the lungs (pleuritis) causes chest pain, especially with deep breathing as the lungs expand against the inflamed areas, as well as shortness of breath. Inflammation of the aorta (aortitis) can cause leakage of the aortic valves, leading to heart failure and shortness of breath.

Acne and nail changes are commonly seen in psoriatic arthritis. Pitting and ridges are seen in fingernails and toenails of 80% of patients with psoriatic arthritis. Interestingly, these characteristic nail changes are observed in only a minority of psoriasis patients who do not have arthritis. Acne has been noted to occur in higher frequency in patients with psoriatic arthritis. In fact, a syndrome exists that features inflammation of the joint lining (synovitis), acne and pustules on the feet or palms, thickened and inflamed bone (hyperostosis), and bone inflammation (osteitis). This syndrome is, therefore, named by the eponym SAPHO syndrome.

Medically Reviewed by a Doctor on 10/2/2013

Patient Comments

Viewers share their comments

Psoriatic Arthritis - Describe Your Experience Question: Please describe your experience with psoriatic arthritis.
Psoriatic Arthritis - Diagnosis Question: How was your psoriatic arthritis diagnosed?
Psoriatic Arthritis - Treatment Question: What was the treatment for your psoriatic arthritis?
Source: MedicineNet.com
http://www.medicinenet.com/psoriatic_arthritis/article.htm

Women's Health

Find out what women really need.

advertisement
advertisement
Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations