There are several types of psoriasis. The most common type of psoriasis is called plaque psoriasis. It causes raised, red patches covered with silvery scales to appear all over the body.
These often itchy and painful patches, otherwise known as plaques, commonly occur on the scalp, knees, elbows, and back.
Scientists do not know exactly what causes psoriasis, although they know that there is a genetic and an immune system component. This is partially because psoriasis affects men and women equally and occurs in all ethnicities and races.
Plaque psoriasis may show up anywhere on the body and will appear as raised, red patches covered in silvery scales.
Psoriasis often develops between the ages of 15 and 35, but can develop at any age.
Plaque psoriasis, like all types of psoriasis, is an autoimmune disorder. Scientists believe that there is a genetic component as it tends to run in families. So, if someone's parent or sibling has plaque psoriasis, then they are more likely to have psoriasis as well.
Genetics are just one risk factor. The immune system also plays a crucial role in the development of psoriasis.
People without a family history of psoriasis can still develop plaque psoriasis. Other risk factors include:
- Recurrent or chronic viral or bacterial infections. People who have HIV or experience multiple strep throat infections are more likely to develop psoriasis than others.
- Obesity. Plaques and sores associated with psoriasis often develop in skin folds and creases.
- Smoking. Tobacco use increases the risk of developing all types of psoriasis, including plaque psoriasis.
- Stress. Stress weakens the immune system. Those with high stress levels may be at increased risk for developing psoriasis.
Plaque psoriasis causes plaques to appear on the surface of the body. The plaques are raised, red patches of skin covered in white or silvery scales.
These plaques may be painful and itchy. Some plaques may bleed or crack. These areas can occur anywhere on the body but are most likely to surface on the elbows, knees, back, and scalp.
While these areas of inflamed skin are the most notable symptoms of plaque psoriasis, other symptoms could occur alongside them. Symptoms may vary from person to person and can include the following:
- Red patches of skin covered with silver or white scales
- Thickened or ridged nails
- Small areas of scaling
- Itching, burning, and soreness
- Painful, swollen joints
These symptoms can occur or worsen for several weeks or months, during a flare. At other times, the symptoms may lessen or even clear up. This cycle tends to repeat itself.
Plaque psoriasis can cause some complications. The plaques may become infected, especially if they are cracked and bleeding.
Additionally, plaque psoriasis patients are at higher risk for the following:
- Psoriatic arthritis
- Other autoimmune disorders including celiac and Crohn's disease
- Heart disease and high blood pressure
- Certain eye problems
- Kidney disease
People with plaque psoriasis may be up to 50 percent more likely to suffer from depression than individuals who are healthy. Plaque psoriasis can lower self-esteem and cause significant emotional and mental impacts, which negatively affect the patient's quality of life.
Conditions with similar symptoms
Psoriasis is sometimes misdiagnosed because the symptoms resemble those of other conditions.
Stress may play a role in triggering a psoriasis flare.
In people with psoriasis, certain types of white blood cell, known as T cells, begin an inflammatory attack on invaders. In healthy people, T cells fight off viruses and bacteria. In people with psoriasis, these T cells attack their own skin cells as if they are injured.
The overactive T cells try to heal a wound that is not present, causing the skin to grow too quickly and build up into patches.
Other immune responses occur that cause the blood vessels in the skin around the plaques to dilate and more white blood cells to be produced. This causes a further buildup of skin that does not shed as quickly as it is formed.
Scientists are not sure what causes the immune system to malfunction in people with psoriasis. They do believe genetics and environmental factors may come into play.
Environmental factors could play a role because certain environmental occurrences trigger psoriasis flares, including:
- Exposure to cold weather
- Skin injuries including cuts, scrapes, and bug bites
- Excess alcohol consumption
- Some medications including beta blockers, lithium, and antimalarial medicines
Diagnosing plaque psoriasis is fairly simple in most cases. A doctor can normally diagnose plaque psoriasis with a thorough physical exam, looking closely at the skin and nails, and examining the patient's medical history.
Occasionally, a doctor may need to take a skin biopsy to confirm diagnosis. Here, a doctor will take a small sample of the patient's skin and examine it closely under a microscope. This can help to determine the exact type of psoriasis and rule out other skin conditions that may look like plaque psoriasis.
When to see a doctor
People with plaque psoriasis should be under the care of a good doctor. Anyone who has plaque psoriasis symptoms should see a healthcare professional.
Those already diagnosed with plaque psoriasis should see a doctor regularly and during periods of flares, particularly if prescribed treatments are not working.
While plaque psoriasis does not have a cure, there are many treatment options available. Treatment generally depends on the severity of the plaque psoriasis.
Treatments include a variety of options, including topical treatments, systemic therapy, light therapy, and lifestyle changes.
Topical treatments are often the first course of action for managing plaque psoriasis. These creams and ointments are applied directly to the skin in order to reduce inflammation and slow down skin cell growth. They may also help to soothe the skin and protect it from infection.
These treatments are likely to be available over the counter or through prescription, and include:
- Corticosteroid creams and lotions
- Topical retinoids
- Vitamin D analogue
- Salicylic acid
Any signs of plaque psoriasis should be directed to a healthcare professional.
Systemic treatments include oral or injected medications that affect the whole body. People with moderate to severe plaque psoriasis may benefit from this type of treatment. Systemic medications for psoriasis include some retinoids, methotraxate, and drugs that alter the immune system, called biologics.
Phototherapy treats psoriasis using natural or artificial light. Phototherapy treatments range from exposing the skin to a small amount of sunlight regularly, in sessions of no more than 10 minutes, to regulated ultraviolet exposure from an artificial light source. In some cases, laser therapy may be used.
Anybody with plaque psoriasis can also make some lifestyle changes to help manage their condition. These lifestyle changes include:
- Taking daily baths and using colloidal oatmeal during flares
- Avoiding extreme hot and cold
- Losing weight
- Avoiding alcohol and tobacco
- Managing and reducing stress
- Using gentle moisturizer