Psoriasis and Psoriatic Arthritis

Psoriasis is a debilitating skin condition that can affect the elbows, knees, scalp, lower back, face and indeed, any part of the body, including the genital area. It may also affect the fingernails and toenails making them thick and discoloured.

Psoriasis is a chronic (long-lasting) skin disease of scaling and inflammation that affects 2 to 2.6 percent of the U.S population, or between 5.8 and 7.5 million people.

Although the disease occurs in all age groups, it primarily affects adults. It appears about equally in males and females. Psoriasis occurs when skin cells quickly rise from their origin below the surface of the skin and pile up on the surface before they have a chance to mature. Usually this movement (also called turnover) takes about a month, but in psoriasis it may occur in only a few days.

In its typical form, psoriasis results in patches of thick, red (inflamed) skin covered with silvery scales. These patches, which are sometimes referred to as plaques, usually itch or feel sore. They most often occur on the elbows, knees, other parts of the legs, scalp, lower back, face, palms, and soles of the feet, but they can occur on skin anywhere on the body.

How Does Psoriasis Affect Quality of Life?

Individuals with psoriasis may experience significant physical discomfort and some disability. Itching and pain can interfere with basic functions, such as self-care, walking, and sleep. Plaques on hands and feet can prevent individuals from working at certain occupations, playing some sports, and caring for family members or a home.

The frequency of medical care is costly and can interfere with an employment or school schedule.

People with moderate to severe psoriasis may feel self-conscious about their appearance and have a poor self-image that stems from fear of public rejection and psychosexual concerns. Psychological distress can lead to significant depression and social isolation.

What Causes Psoriasis?

Psoriasis is a skin disorder. T cells help protect the body against infection and disease. In the case of psoriasis, T cells are put into action by mistake and become so active that they trigger other immune responses, which lead to inflammation and to rapid turnover of skin cells.

People with psoriasis may notice that there are times when their skin worsens, then improves.

Conditions that may cause flareups include infections, stress, and changes in climate that dry the skin. Also, certain medicines, including lithium and betablockers, which are prescribed for high blood pressure, may trigger an outbreak or worsen the disease.

How Is Psoriasis Diagnosed?

Occasionally, doctors may find it difficult to diagnose psoriasis, because it often looks like other skin diseases. It may be necessary to confirm a diagnosis by examining a small skin sample under a microscope.

There are several forms of psoriasis. Some of these include:

Plaque psoriasis Skin lesions are red at the base and covered by silvery scales.

Guttate psoriasis Small, drop-shaped lesions appear on the trunk, limbs, and scalp. Guttate psoriasis is most often triggered by upper respiratory infections (for example, a sore throat caused by streptococcal bacteria).

Pustular psoriasis Blisters of noninfectious pus appear on the skin. Attacks of pustular psoriasis may be triggered by medications, infections, stress, or exposure to certain chemicals.

Inverse psoriasis Smooth, red patches occur in the folds of the skin near the genitals, under the breasts, or in the armpits. The symptoms may be worsened by friction and sweating.

Erythrodermic psoriasis Widespread reddening and scaling of the skin may be a reaction to severe sunburn or to taking corticosteroids (cortisone) or other medications. It can also be caused by a prolonged period of increased activity of psoriasis that is poorly controlled.

Psoriatic arthritis Joint inflammation that produces symptoms of arthritis in patients who have or will develop Psoriasis.

Blood tests conducted for this condition may rule out other conditions such as gout or rheumatoid arthritis. There is a particular antibody normally present in rheumatoid arthritis that is not present in psoriatic arthritis. These tests will often also show elevated erythrocyte sedimentation rate or ESR which measures inflammation. They often show mild anaemia and elevated levels of uric acid.

Prescribed Methotrexate, an immunosuppressive drug. This medication has been used very successfully in the treatment of psoriasis and psoriatic arthritis.

Methotrexate works by binding to and inhibiting an enzyme involved in the rapid growth of cells, thus slowing down the rate of skin cell growth. It was originally used in the treatment of cancer but was discovered in the 1950s to be effective in the treatment of psoriasis and was eventually approved for use in this condition in the 1970s.

Methotrexate is generally well tolerated in small doses but it does potentially have a number of side effects. For this reason, it is imperative that a patient on this drug follows the instructions of their physician very carefully. People taking this medication need to have regular blood tests to be sure that the body is processing the drug safely and not creating other problems, particularly in the liver.

Further Information Regarding Psoriasis and Psoriatic Arthritis

Psoriasis - A Disability with Emotional and Physical Toll
Psoriasis is a real disability that affects approximately one million Canadians. A recent Canadian survey found that the causes and effects of this chronic, recurrent skin disorder are often misunderstood - and the result of these misperceptions can leave a lasting negative impact on those who suffer from this debilitating immune system disease.