Advertisement

What causes psoriasis?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

Psoriasis is most likely caused by a malfunctioning immune system. In this particular case, the malfunction has to do with white blood cells known as T cells. If you have psoriasis, your T cells aren't operating as they should, causing inflammation and a buildup of extra skin cells. Unfortunately, no one knows what causes this malfunction. But in addition to knowing that the condition has something to do with your immune system, researchers have also linked it to genetics. Several genes responsible for psoriasis have already been identified. Your environment can play a role too, and it's possible that psoriasis may be caused by a combination of all three of these factors.

We don’t know exactly what causes psoriasis, but it appears that a combination of factors contribute to its development. Basically, psoriasis starts with inflammation in the skin that prompts new skin cells to develop. The process starts in the basal (bottom) layer of the epidermis, where keratinocytes are made. Keratinocytes are epidermal skin cells that produce keratin, a tough protein that helps form hair, nails, and skin. In normal cell growth, keratinocytes grow and move from the bottom layer to the skin’s surface and shed unnoticed. This process takes about a month.

In people with psoriasis, the keratinocytes multiply very rapidly and travel from the basal layer to the surface in about three to four days. The skin cannot shed these cells quickly enough, so they build up, leading to thick, dry plaques. Silvery, flaky areas of dead skin build up on the surface of the plaques. The underlying skin layer (dermis), which contains the nerves, blood, and lymphatic vessels, becomes red and swollen.

From The Mind-Beauty Connection: 9 Days to Less Stress, Gorgeous Skin, and a Whole New You by Amy Wechsler.

Continue Learning about Plaque Psoriasis

What Has Been Your Experience With Biologic Treatment?
What Has Been Your Experience With Biologic Treatment?
Patient and advocate Alisha Bridges has tried a number of biologic treatments over the past 10 years. In this video, she talks about finding a treatme...
Read More
One-to-One: Psoriasis in the Spring
One-to-One: Psoriasis in the Spring
Do you get terrible psoriasis flare-ups in the Spring? Dermatologist Dr. Doris Day has some advice for you to get out and enjoy the season.
Read More
7 Psoriasis Triggers to Avoid—and What to Do Instead
7 Psoriasis Triggers to Avoid—and What to Do Instead
When the red, itchy patches of psoriasis flare up, it interrupts daily life until you can get your symptoms under control. We know genetics plays a ro...
Read More
What increases my risk for plaque psoriasis?
Diana MeeksDiana Meeks
Anyone may get plaque psoriasis but there are a number of factors that increase risk. One factor is ...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.