Psoriatic Arthritis Causes
The cause of psoriatic arthritis is unknown. As in psoriasis, genetic factors appear to
be involved. People with psoriatic arthritis are more likely than others to have close
relatives with the disease, but they are just as likely to have relatives with psoriasis
but no joint disease. Researchers believe genes increasing the susceptibility to
developing psoriasis may be located on chromosome 6p and chromosome 17, but the specific
genetic abnormality has not been identified. Like psoriasis and other forms of arthritis,
psoriatic arthritis also appears to be an autoimmune disorder, triggered by an attack of
the body's own immune system on itself.
Psoriatic Arthritis Causes - different types
Physicians recognize a number of different forms of psoriatic arthritis. In some
patients, the arthritic symptoms will affect the small joints at the ends of the fingers
and toes. In others, symptoms will affect joints on one side of the body but not on the
other. In addition, there are patients whose larger joints on both sides of the body
simultaneously become affected, as in rheumatoid arthritis. Some people with psoriatic
arthritis experience arthritis symptoms in the back and spine; in rare cases, called
psoriatic arthritis mutilans, the disease destroys the joints and bones, leaving patients
with gnarled and club-like hands and feet. In many patients, symptoms of psoriasis precede
the arthritis symptoms; a clue to possible joint disease is pitting and other changes in
the fingernails.
Most people develop psoriatic arthritis between ages 35-45, but it has been observed
earlier in adults and children. Both the skin and joint symptoms will come and go; there
is no clear relationship between the severity of the psoriasis symptoms and arthritis pain
at any given time. It is unclear how common psoriatic arthritis is. Recent surveys suggest
that between 1 in 5 people and 1 in 2 people with psoriasis may also have some arthritis
symptoms |
