Psoriatic arthritis is a condition in which a person has both psoriasis and a related form of arthritis. Psoriasis is a common skin condition. A person with psoriasis typically has patches of raised red skin with scales. The affected skin can look different depending on the type of psoriasis the individual has. Arthritis is joint inflammation. Psoriatic arthritis is a particular type of aggressive and potentially destructive, inflammatory arthritis.
Psoriatic arthritis is an autoimmune disease, meaning that your cells and antibodies (part of your immune system) attack your own tissues. Rarely, a person can have psoriatic arthritis without having obvious psoriasis. Usually, the more severe the skin symptoms are, the greater the likelihood a person will have psoriatic arthritis.
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