What is psoriasis? | Science live

Psoriasis is a disease that causes people to develop thick patches of inflamed skin covered with silvery scales. It is an autoimmune disease, which means that the immune system becomes hyperactive and mistakenly attacks healthy cells in the body.

With psoriasis, a hyperactive immune system causes skin cells to grow too quickly: new skin cells form within days, not weeks, causing them to develop rapidly on the surface of the skin, forming skin cells. plaques and thick scales that are characteristic of psoriasis, according to the National Psoriasis Foundation.

In light-skinned people, psoriasis resembles an over-whitish salmon-pink plaque, said Dr. David Rosmarin, a dermatologist at Tufts Medical Center in Boston. The most commonly affected places are the elbows, knees, scalp, lower back and back, and the genitals can also be affected, he said.

According to the American Academy of Dermatology, these skin patches appear more purple or purplish, with a gray scale, in dark-skinned people.

In the United States, about 7.5 million people suffer from psoriasis. The most common type is plaque psoriasis, which affects about 80% of people, according to the American Academy of Dermatology.

Plaque psoriasis is one of five types of psoriasis that affects adults and children. (The other four types are guttate, pustular, reverse and erythrodermic.) It's possible to have more of one type of psoriasis at the same time, said Rosmarin. [5 Ways Skin Can Signal Health Problems]

What does psoriasis look like?

Itching is the most common complaint in people with psoriasis, Rosmarin told Live Science. People feel itchy, especially when psoriasis affects their scalp, palms or soles, he said.

According to the Mayo Clinic, the most common physical symptoms of plaque psoriasis include:

• Skin with pink to red relief plaques called plaque.
• The patches can be covered with a silver-white coating called balance.
• The skin can be itchy, burns, bites or painful.
• Patches that can crack and bleed.
• Nails and nails may appear stitched, cracked, thickened or friable and may be mistaken for nail fungus.

Skin disease can also have psychological consequences, as evidenced by the higher rates of depression, anxiety, and substance abuse seen in people with psoriasis, Rosmarin said.

Psoriasis can appear anywhere on the skin and patches may appear separately or join to cover a larger area. When patches and scales are in visible places, people with psoriasis may feel embarrassed or withdraw socially.

"Some of my psoriasis patients will not come out with shorts or short-sleeved shirts in the summer," said Rosmarin. Likewise, some of Rosmarin's scalp psoriasis patients refuse to wear black shirts because they are worried about visible dandruff from their scales, he says.

(Image credit: Shutterstock)

Causes, risk factors and triggers

The cause of psoriasis is unclear, but an overactive immune system as well as genetic and environmental factors could be responsible for it, Rosmarin said. People with a family history of psoriasis and those who have had viral or bacterial infections, such as strep or skin infections, are more likely to develop psoriasis, he said. But psoriasis is not contagious and a person can not get it by touching the skin patches of someone who is suffering from it.

Another theory is that psoriasis can be caused by a traumatic skin lesion, such as burns, animal bites or tattoos, said Rosmarin.

According to the National Psoriasis Foundation, the following factors can trigger psoriasis flares and worsen the condition of it for a few weeks or months.

• Infections, such as throat or skin infections. Psoriasis can break out in children two to six weeks after an earache, tonsillitis, bronchitis or respiratory infection.
• Injury to the skin, such as a cut, a scratch or a bad sunburn.
• Stress can cause a first flare of psoriasis or aggravate skin disorders in those who already suffer.
• Use of certain drugs, such as beta-blockers, lithium and antimalarials.

Diagnosis and treatment

A dermatologist will examine the signs of psoriasis on a person's skin, nails and scalp, and will also ask if any members of the family are suffering from the disease. If there is suspicion of psoriasis, a small sample of affected skin (biopsy) can be taken and examined under a microscope: skin with psoriasis appears thicker and inflamed than skin containing eczema, for example.

Psoriasis can develop at any age. People are usually diagnosed in their twenties, but there is a smaller peak period between 50 and 60 years, said Rosmarin.

With current advances in treatment methods, dermatologists can help the vast majority of psoriasis patients far more than it could have done a decade ago, Rosmarin told Live Science.

People with psoriasis can benefit from four categories of treatment: topical creams and ointments; phototherapy (exposure to ultraviolet light); oral medications; and biologics, which are drugs given by injection (injections) or intravenously, said Rosmarin. The treatment that a person with psoriasis receives depends on the severity of his case and his general state of health.

Arthritis and other health effects

Although psoriasis is a skin disease, it can influence a person's health in many ways. For example, some people with psoriasis have an increased risk of developing psoriatic arthritis, an inflammatory arthritic form. About a third of people with psoriasis contract this type of arthritis, which causes pain and joint stiffness, Rosmarin said. Without treatment, psoriatic arthritis can cause structural damage to the affected joints, he said.

People with moderate to severe forms of psoriasis also run a higher risk of cardiovascular disease, such as heart attacks and strokes, Rosmarin said. This could be because psoriasis causes long-lasting inflammation in the body, which can affect the skin and joints, as well as the heart and blood vessels, he said.

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This article is for informational purposes only, and is not intended to offer medical advice.