CausesBy Mayo Clinic staff
Psoriatic arthritis occurs when your body's immune system begins to attack healthy cells and tissue. The abnormal immune response causes inflammation in your joints as well as overproduction of skin cells.
It's not entirely clear why the immune system turns on healthy tissue, but it seems likely that both genetic and environmental factors play a role. Many people with psoriatic arthritis have a family history of either psoriasis or psoriatic arthritis. Researchers have discovered certain genetic markers that appear to be associated with psoriatic arthritis.
Physical trauma or something in the environment — such as a viral or bacterial infection — may trigger psoriatic arthritis in people with an inherited tendency.
- Fitzgerald O. Psoriatic arthritis. In: Firestein GS, et al. Kelley's Textbook of Rheumatology. 8th ed. Philadelphia, Pa.: W.B. Saunders Co.; 2008. http://www.mdconsult.com/das/book/body/223128990-5/1070709009/1807/528.html#4-u1.0-B978-1-4160-3285-4..10072-5_2607. Accessed Oct. 19, 2010.
- Gladman DD. Clinical manifestations and diagnosis of psoriatic arthritis. http://www.uptodate.com/home/index.html. Accessed Oct. 19, 2010.
- Psoriatic arthritis. American College of Rheumatology. http://www.rheumatology.org/practice/clinical/patients/diseases_and_conditions/psoriaticarthritis.asp. Accessed Oct. 19, 2010.
- Kleinert S, et al. Psoriatic arthritis: Clinical spectrum and diagnostic procedures. Clinics in Dermatology. 2007;25:519.
- Gladman DD. Pathogenesis of psoriatic arthritis. http://www.uptodate.com/home/index.html. Accessed Oct. 19, 2010.
- Mercier LR. Arthritis, psoriatic. In: Ferri FF. Ferri's Clinical Advisor 2011. Philadelphia, Pa.: Mosby Elsevier; 2010. http://www.mdconsult.com/books/page.do?sid=1070709009&eid=4-u1.0-B978-0-323-07158-1..00003-1--s2020&isbn=978-0-323-07158-1&type=bookPage§ionEid=4-u1.0-B978-0-323-07158-1..00003-1--s2020&uniqId=223128990-6. Accessed Oct. 19, 2010.
- Gladman DD. Treatment of psoriatic arthritis. http://www.uptodate.com/home/index.html. Accessed Oct. 19, 2010.
- Chang-Miller A (expert opinion). Mayo Clinic, Scottsdale, Ariz. Nov. 2, 2010.