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Disease Areas Psoriasis
 

Psoriasis

Psoriasis is a common, chronic, immune-mediated inflammatory disease with symptoms that mostly affect the skin.  Patients with psoriasis may have some or all of the following symptoms:

  • red patches of skin covered with silvery scales,
  • cracked skin that may bleed and thicken,
  • severe itching and pitted or ridged nails.

Because of its visible and physically debilitating aspects, psoriasis often takes an emotional toll on patients, causing increased self-consciousness, frustration, fatigue, depression, and even suicidal ideation.

People living with psoriasis frequently report sleeping problems, difficulties at work, problems interacting with family members, disrupted leisure activities, and sexual difficulties. Patients also report that the significant impact of this disease on their quality of life is not well understood by their physicians.

Psoriasis affects nearly three percent of the world's population, or approximately 125 million people worldwide.


Women and men of all ages and ethnicities are affected by psoriasis. Psoriasis has a variety of forms, though plaque psoriasis is most common, comprising approximately 80% to 90% of all cases. Several other serious diseases have been associated with psoriasis, including diabetes, heart disease, and psoriatic arthritis, a chronic disease that causes inflammation, swelling, and pain in the joints.

As research continues to demonstrate the serious, systemic effects of psoriasis, new research approaches to understand effective treatment options are needed to improve the health and lives of psoriasis patients.

The cause of psoriasis isn't fully known
Psoriasis is thought to be related to an immune system problem with cells in the body. More specifically, one key cell is a type of white blood cell called a T lymphocyte or T cell. Normally, T cells travel throughout the body to detect and fight off foreign substances, such as viruses or bacteria. In psoriasis, however, the T cells attack healthy skin cells by mistake, as if to heal a wound or to fight an infection.

Overactive T cells trigger other immune responses. The effects include dilation of blood vessels in the skin around the plaques and an increase in other white blood cells that can enter the outer layer of skin. These changes result in an increased production of both healthy skin cells and more T cells and other white blood cells. This causes an ongoing cycle in which new skin cells move to the outermost layer of skin too quickly — in days rather than weeks. Dead skin and white blood cells can't slough off quickly enough and build up in thick, scaly patches on the skin's surface. This usually doesn't stop unless treatment interrupts the cycle.

Just what causes T cells to malfunction in people with psoriasis isn't entirely clear. Researchers have found genes that are linked to the development of psoriasis, but environmental factors also play a role.

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Factors that may trigger psoriasis include:

  • Infections, such as strep throat or skin infections
  • Injury to the skin, such as a cut or scrape, bug bite, or a severe sunburn
  • Stress
  • Cold weather
  • Smoking
  • Heavy alcohol consumption
  • Certain medications — including lithium, which is prescribed for bipolar disorder; high blood pressure medications such as beta blockers; antimalarial drugs; and iodides.

Anyone can develop psoriasis, but these factors can increase the risk of developing the disease:

  • Family history. Perhaps the most significant risk factor for psoriasis is having a family history of the disease. Having one parent with psoriasis increases your risk of getting the disease, and having two parents with psoriasis increases your risk even more.
  • Viral and bacterial infections. People with HIV are more likely to develop psoriasis than people with healthy immune systems are. Children and young adults with recurring infections, particularly strep throat, also may be at increased risk.
  • Stress. Because stress can impact your immune system, high stress levels may increase your risk of psoriasis.
  • Obesity. Excess weight increases the risk of psoriasis. Plaques associated with all types of psoriasis often develop in skin creases and folds.
  • Smoking. Smoking tobacco not only increases your risk of psoriasis but also may increase the severity of the disease. Smoking may also play a role in the initial development of the disease.

Several types of psoriasis exist. These include:

  • Plaque psoriasis. The most common form, plaque psoriasis causes dry, raised, red skin lesions (plaques) covered with silvery scales. The plaques itch or may be painful and can occur anywhere on your body, including your genitals and the soft tissue inside your mouth. You may have just a few plaques or many.
  • Nail psoriasis. Psoriasis can affect fingernails and toenails, causing pitting, abnormal nail growth and discoloration. Psoriatic nails may become loose and separate from the nail bed (onycholysis). Severe cases may cause the nail to crumble.
  • Scalp psoriasis. Psoriasis on the scalp appears as red, itchy areas with silvery-white scales. The red or scaly areas often extend beyond the hairline. You may notice flakes of dead skin in your hair or on your shoulders, especially after scratching your scalp.
  • Guttate psoriasis. This primarily affects young adults and children. It's usually triggered by a bacterial infection such as strep throat. It's marked by small, water-drop-shaped sores on your trunk, arms, legs and scalp. The sores are covered by a fine scale and aren't as thick as typical plaques are. You may have a single outbreak that goes away on its own, or you may have repeated episodes.
  • Inverse psoriasis. Mainly affecting the skin in the armpits, in the groin, under the breasts and around the genitals, inverse psoriasis causes smooth patches of red, inflamed skin. It's worsened by friction and sweating. Fungal infections may trigger this type of psoriasis.
  • Pustular psoriasis. This uncommon form of psoriasis can occur in widespread patches (generalized pustular psoriasis) or in smaller areas on your hands, feet or fingertips. It generally develops quickly, with pus-filled blisters appearing just hours after your skin becomes red and tender. The blisters may come and go frequently. Generalized pustular psoriasis can also cause fever, chills, severe itching and diarrhea.
  • Erythrodermic psoriasis. The least common type of psoriasis, erythrodermic psoriasis can cover your entire body with a red, peeling rash that can itch or burn intensely.
  • Psoriatic arthritis. In addition to inflamed, scaly skin, psoriatic arthritis causes pitted, discolored nails and the swollen, painful joints that are typical of arthritis. Symptoms range from mild to severe, and psoriatic arthritis can affect any joint. Although the disease usually isn't as crippling as other forms of arthritis, it can cause stiffness and progressive joint damage that in the most serious cases may lead to permanent deformity.
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Victoria, living with psoriasis