If you suffer from psoriasis, you might be surprised to learn it’s not just the skin that might need treatment.
“Psoriasis is an autoimmune disease,” said Dr. Sylvia Hsu, professor of dermatology at Baylor College of Medicine. “In about 10 percent of cases the disorder will affect the joints, a condition known as psoriatic arthritis.”
The first symptom of psoriasis is usually an itchy rash, caused by an over production of skin cells. This is why many think it is a solely a skin disorder. It is usually limited to a few patches of skin but most commonly affects the scalp, elbows, and knees. The rash can heal and come back throughout a person’s life.
“Joint problems usually don’t appear at the same time skin problems do,” said Hsu. “Skin issues might appear first, and then years later the joints start to become inflamed, or vise versa.”
In most cases the joint problems aren’t severe, Hsu said. Many people may find they are stiff in the morning or become achy as the day goes on.
The cause of the disorder isn’t fully understood but it is attributed to an abnormality in the immune system involving T cells, which help coordinate immune responses.
“We see a higher level of T cells in psoriasis skin plaques,” said Hsu. “We also see elevated levels in the affected joints.”
Treatment for the two symptoms can be given separately by a dermatologist or a rheumatologist since the skin and joint problems can appear at different times. A form of treatment known as biologic therapy can be used to treat both. It can be given through injection and works by targeting the specific immune pathways that cause inflammation on the skin and in the joints.
“There is no cure for psoriasis but as doctors begin to better understand the cause of the disorder, therapies are becoming more effective and longer lasting,” said Hsu.