Because the symptoms of plaque psoriasis appear on the surface of your skin, you might think the problem starts there. In fact, plaque psoriasis begins beneath the surface, by shortening the normal life cycle of your skin cells. In healthy skin, cells mature, rise to the surface, and are shed every 28 to 30 days. Skin cells affected by plaque psoriasis, however, mature in only 3 to 5 days–much faster than your body can shed them.
While the direct cause of plaque psoriasis is unknown, here's what we do know: First, you may be more likely to experience plaque psoriasis if it's part of your family's medical history. Second, plaque psoriasis symptoms begin when your immune system attacks healthy cells in your body, for reasons we do not yet understand.
Normally, your immune system (the body's natural defense system), protects your body from bacteria, viruses, and other foreign agents. Research has suggested that plaque psoriasis may be linked to an overactive immune system, which causes the body to accelerate the growth of skin cells at a faster pace than usual. As a result, thickened, red patches, covered by silvery scales appear on the surface of your skin. Doctors refer to these as psoriatic plaques.
In the United States, as many as 7.5 million people have been diagnosed with plaque psoriasis. Plaque psoriasis affects men and women equally, but research has suggested that ethnicity may be a factor. Psoriasis is more common among Caucasians of European descent than among African Americans or Asians. Symptoms of plaque psoriasis usually appear between the ages of 15 and 25. About a third of people who have plaque psoriasis have a family history of the disease.
Only a dermatologist can determine if you have plaque psoriasis. If you're diagnosed with chronic severe plaque psoriasis, your dermatologist may prescribe REMICADE® as part of your treatment plan.
Plaque psoriasis is characterized by thickened, red patches covered by silvery scales, which appear on the surface of your skin, and may itch or feel sore. They can occur anywhere on your body in just a few places, or over large areas of your body.
There's no specific diagnostic test for plaque psoriasis. If you experience symptoms, make an appointment with a dermatologist. The dermatologist will discuss your symptoms and may ask questions about your family medical history. Your dermatologist will also look at your skin for symptoms and may decide to take a biopsy. A biopsy is a sample of the affected skin. Your dermatologist will examine this sample under a microscope to rule out other possible skin conditions.