More On The Causes Of Psoriasis

Psoriasis is a skin condition marked by a rapid buildup of rough, dry, dead skin cells that form thick scales. Arthritis causes pain and stiffness in your joints. Both are autoimmune problems — disorders that occur when your body's immune system, which normally fights harmful organisms such as viruses and bacteria, begins to attack healthy cells and tissue. The abnormal immune response causes inflammation in your joints as well as the overproduction of skin cells.
It's not entirely clear why the immune system turns on itself, but it seems likely that both genetic and environmental factors play a role. Many people with psoriatic arthritis have a close relative, such as a parent or sibling, with the disease, and researchers have discovered certain gene mutations that appear to be associated with psoriatic arthritis.
Having a genetic mutation doesn't necessarily mean you'll develop the disease, but it does mean you have a greater tendency to do so than other people do. Something in the environment — such as a viral or bacterial infection or even physical trauma — may eventually trigger psoriatic arthritis in people who have an inherited tendency.
A number of other factors may trigger psoriatic arthritis, including:
Injury to your skin
Reaction to a medication or vaccine
Infection, especially streptococcal
Stress
Alcohol and poor nutrition
Overexposure to the sun or prolonged exposure to irritating chemicals such as disinfectants and paint thinners