Psoriasis is a common chronic inflammatory skin condition usually characterized by red elevated patches and flaking silvery scales. Symptoms can range from mild to severe.

Symptoms can include:
  • Dry or red areas of skin, usually covered with silvery-white scales and sometimes with raised edges
  • Rashes on the scalp, genitals, or in the skin folds
  • Itching and skin pain, sometimes severe
  • Joint pain, swelling or stiffness
  • Nail abnormalities

While lesions can appear anywhere on the body, the most common sites include elbows, knees, scalp, chest and lower back.

Who is at risk?

Psoriasis can develop at any age, although it is typically seen in adults. One form of psoriasis called guttate psoriasis tends to occur in childhood and early adulthood. Psoriasis occurs equally among men and women.

What causes it?

Psoriasis has a genetic basis and about one-third of people with psoriasis have at least one family member with the disease. While the exact cause of psoriasis has not yet been determined, researchers believe it involves a combination of genetic, environmental and immune factors.

Psoriasis develops when there is a malfunctioning of the immune system which causes inflammation.

White blood cells (T cells) in the immune system are triggered and this causes inflammation to occur, which then causes skin cells to rise to the surface and shed at 10 times the normal rate

Psoriasis
Psoriasis
Psoriasis

Psoriasis has a broad impact on patients that extends beyond the cosmetic or physical aspects. It can negatively affect a person’s quality of life due to physical pain and discomfort.

Psoriatic lesions can be itchy, painful and bleed, making it difficult to sleep, dress or engage in various daily activities. If there is joint involvement, the pain can also make it challenging for the individual to function physically.

People with psoriasis have an increased risk of depression, anxiety and suicide

According to a national patient survey, psoriasis and related conditions “impose a severe burden on the daily lives of Canadians with a history of moderate to severe psoriasis.” Over one third of respondents (176 of 500) viewed their skin condition as a significant problem in their daily life. The perception seemed to correlate with the extent of disease.

The aim of treatment is ultimately to reach an appropriate quality of life.

Quick facts about psoriasis
  • Psoriasis affects 1 million Canadians and 125 million people worldwide.
  • The most common form is plaque psoriasis, which affects approximately 90% of patients.
  • Up to 30% of patients with psoriasis have or will have arthritis. Having psoriasis may increase the risk of developing other chronic systemic diseases, including heart attack and stroke, diabetes, cancer, and liver disease.

Diagnosis of psoriasis involves taking a careful history and conducting a physical examination.

Psoriasis can take on a variety of forms, which include plaque, guttate, pustular, inverse and erthyrodermic. Some of these types may evolve from plaque psoriasis.

Plaque psoriasis is the most common form and it occurs in about 90% of patients.It usually begins with red scaly patches. The symptoms can range from mild to severe, covering very small or extensive areas of the body.

Guttate psoriasis is typically of abrupt onset, appearing in a few weeks, being often quite extensive. It is marked by lesions that are small and “drop-like”, which often appear on the trunk (i.e. lower back), arms, legs or scalp. It makes up about 10% of psoriasis cases and is the second most common form. It often develops following an upper respiratory infection, often strep throat, which acts as the trigger. Guttate psoriasis can resolve on its own without treatment, and the individual may never develop psoriasis again.  Or it can become recurrent throughout life. Sometimes, it can become severe, persistent and require treatment.

Pustular psoriasis is characterized by pustules (pus-filled bumps) and can sometimes be disabling and life-threatening. It can be limited to certain areas of the body (localized) or widespread (generalized). If localized, the pustules are usually confined to the palms and soles of the feet. Scales gradually form as pustular lesions dry out.

Inverse psoriasis occurs in skin folds (also called “flexures”) where there tends to be pressure, friction and/or moisture or perspiration, such as between buttocks, the genitals, under breasts and armpits. These lesions are smooth and red as opposed to raised and scaling.

Erythrodermic psoriasis is a rare but serious form of disease marked primarily by widespread redness and inflammation that resembles sunburn. It can result from severe sunburn, using certain medications (i.e. oral corticosteroids, lithium) or suddenly stopping psoriasis treatment. It can also stem from poorly controlled psoriasis. It can be life-threatening and usually requires hospitalization since the skin loses its ability to perform vital functions, such as controlling body temperature and protecting against infectious organisms (i.e. bacteria).

A Note About Psoriatic Arthritis

In addition to its obvious effects on the skin, psoriasis can also affect other body tissues. Some patients with psoriasis can develop a kind of arthritis called Psoriatic Arthritis. This may be considered a disease in its own right, may be severe and involves inflammation, stiffness and pain within joints (arthritis) in addition to skin plaques. The skin plaques and joint pain do not coincide, so a flare-up may consist of joint pain in the absence of visible lesions or vice-versa. Typically, the arthritic component develops about a decade after the skin plaques.

For more information

Accurate medical information can also be found on the American Academy of Dermatology website at PsoriasisNet, the US National Psoriasis Foundation website and the New Zealand Dermatological Society website.

Psoriasis may be permanent or episodic, meaning that it can flare up then subside and disappear altogether for a while before another episode occurs.

Triggers or precipitating factors may cause a flare-up in disease or even lead to the development of psoriasis. These factors include emotional stress, local injury to skin, systemic infections, and the use of certain medications.

Infection such as upper respiratory bacteria or viruses can cause someone to develop psoriasis or case psoriasis to worsen.

Skin injury or any break in the skin can cause psoriasis to spread or lead to the development of new lesions. This can include a razor nick or burn, an insect bite, cut, abrasion, sunburn, needle puncture (from vaccination), blister or bruise.

Medications such as lithium (an antidepressant), beta-blockers (commonly prescribed for high blood pressure) and, rarely, anti-malarial drugs can also predispose one to a flare-up or cause psoriasis to first appear.  Oral corticosteroids can worsen psoriasis symptoms with overuse or if treatment is stopped abruptly.

Stress is a factor in a number of health conditions and seems to be a trigger for psoriasis as well. It can also worsen symptoms. Living with psoriasis also contributes to stress, which in turn, can negatively affect the skin condition.

Weather is another factor that can cause psoriasis to improve or worsen. In particular, the dry cold winter season seems to adversely impact on psoriasis because it dries and irritates the skin.

Smoking and being overweight have been shown to increase the risk of developing psoriasis and its severity.

Q: Can I catch psoriasis by touching someone with the disease?
A: No, psoriasis is not contagious. It is not an infectious disease.

Q: Will treatment make psoriasis go away permanently?
A: Effective treatment can send psoriasis into remission, making symptoms disappear for weeks to months at a time but there is not yet a permanent cure for the disease.

Q: Is it possible to prevent psoriasis?
A: If you have a family history, you can help to prevent or minimize the chances of developing psoriasis by reducing stress, avoiding smoking, obesity or being over-weight and discussing with your physician any medications you take.

Q: What happens if I stop treatment?
A: Psoriasis often returns after treatment is stopped. Stopping some treatments abruptly, such as corticosteroids, can rarely trigger a more severe form of psoriasis.

Q: Can I have more than one type of psoriasis?
A: An individual can have different forms of psoriasis appearing at once or at different times.

There are several treatments available to help manage psoriasis.

Determining the most appropriate treatment depends on the type and severity of disease, how large or widespread plaques are, how well a patient responds to a given treatment, and on patient preferences.

A physician may change a patient’s treatment dose, combine one kind of therapy with another, or switch treatments if one doesn’t work for a patient.

Topical

Topically applied treatments, such as creams and ointments, are usually recommended first, particularly for mild psoriasis. The aim of this kind of treatment is primarily to slow down and regulate skin cell turnover, reduce inflammation and suppress the immune system. Topical options can include topical corticosteroids, vitamin D3 analogues, retinoids, calcineurin inhibitors, anthralin and coal tar.

Corticosteroids are the most widely used agents for the topical treatment of psoriasis and have been the mainstay of therapy for decades. Potent topical corticosteroid creams work best for psoriasis.

Physicians may recommend a combination of these topical agents or combine them with oral and/or light therapy.

Oral Medications

A number of oral drugs can help to manage psoriasis and are usually reserved for the treatment of more severe and/or widespread symptoms.

These drugs include methotrexate, cyclosporine, acitretin and apremilast.

Biologics

Biologics are newer forms of treatment given by injection or infusion. These are large molecules that block very specific inflammation pathways and can be highly effective for more serious psoriasis.

Biologics approved for use as treatment for psoriasis in Canada include etanercept and the monoclonal antibodies adalimumab, infliximab, ustekinumab, secukinumab and ixekizumab. The choice amongst these drugs is based upon multiple factors.

Light Therapy

Both natural and artificial ultraviolet (UV) light are used to treat psoriasis. Many patients with psoriasis find that sunlight exposure seems to improve their skin symptoms. One form of light therapy is Narrow Band UVB phototherapy, which emits a short wavelength of UV light that penetrates the epidermis or outermost layer of skin. This is a specialized form of light, different that a tanning booth, and that has not been shown to increase risk of skin cancer. Another form of light therapy is psoralen and UVA (PUVA), which combines an oral or topical form of the drug, psoralen, and UVA light exposure. The drug makes the skin more sensitive to the UVA light, helping it to work better.

Combination Therapy

The challenge for both physician and patient is to find what works most effectively for the individual. Often, two or more treatments may be combined for the best outcome.