What is Psoriasis?

Psoriasis is an autoimmune disease that is currently incurable. Although primarily affecting the skin, it can also impact nails and bones. It is estimated that 1-3 percent of the global population suffers from this condition, which can manifest on any area of the body. There are five main types of psoriasis: plaque, guttate, inverse, pustular, and erythrodermic. Among these, plaque psoriasis is the most prevalent, affecting approximately 85-90% of individuals with the disease.

Symptoms

Plaque Psoriasis

Plaque psoriasis is characterized by red, raised, itchy plaques on the skin’s surface, accompanied by a white-silvery scale. This type may cause discomfort and commonly appears on areas such as the elbows, knees, shins, scalp, and back.

Guttate Psoriasis

The second most common type, guttate psoriasis, often begins in childhood or young adulthood. It presents as numerous small, red spots on the skin, typically affecting the trunk and limbs.

Inverse Psoriasis

Inverse psoriasis is a painful variant that occurs in skin folds, such as those found in the genitals, armpits, and beneath breasts or buttocks. This type can be particularly challenging to manage.

Pustular Psoriasis

Pustular psoriasis is a rare form that appears as defined, raised bumps filled with pus, a thick fluid made up of white blood cells.

Erythrodermic Psoriasis

Erythrodermic psoriasis is marked by widespread red, dry skin covering large areas of the body. This type is generally observed in individuals who have unstable plaque psoriasis and, while rare, it can lead to severe complications that may be fatal.

Causes and Risk Factors

Various risk factors are believed to increase the likelihood of developing psoriasis. Among these are genetic predisposition, immune system irregularities, and environmental triggers.

Genetics

Genetic factors play a significant role, with approximately one-third of patients reporting a family history of the disease.

Immune Response

An abnormal immune system response is thought to contribute to the onset of psoriasis. This overstimulation of skin cells results in a rapid turnover, with skin cells being replaced every 3-5 days instead of the typical 28-30 days.

Environmental Triggers

Patients often identify environmental factors that provoke flare-ups. Common triggers include certain medications (such as beta-blockers), infections (like strep throat), changes in weather, skin injuries, and stress. Lifestyle factors, including smoking and alcohol consumption, may also exacerbate the condition.

Diagnosis

Psoriasis is typically diagnosed by a family physician or dermatologist through careful examination of the skin and nails, along with a comprehensive review of the patient’s medical history. In cases where the diagnosis is uncertain, a skin biopsy may be performed. Blood tests can help rule out other potential causes, and fungal cultures may be conducted to differentiate psoriasis from conditions like candida.

Complications

As an autoimmune disease, psoriasis can increase the risk of other autoimmune conditions, such as Crohn’s disease and celiac disease. Individuals with psoriasis are also more likely to experience cardiovascular issues, elevated blood pressure, and type 2 diabetes compared to the general population. Eye disorders, including conjunctivitis, blepharitis, and uveitis, are also more prevalent among those with psoriasis. One significant complication is psoriatic arthritis, which can result in joint damage and loss of function, leading to debilitating effects. Additionally, the psychological impact of psoriasis can lead to social and emotional challenges, causing distress, frustration, depression, and weight gain.

Treatments

Treatment for psoriasis varies based on the severity of the disease, and an individualized approach is essential, often involving some trial and error.

Topical Therapies

Topical treatments are applied directly to the affected skin and are typically used for smaller areas. These include creams, lotions, ointments, and gels containing steroids, coal tar, anthralin, Vitamin D analogues (like calcipotriol), calcineurin inhibitors (such as tacrolimus and pimecrolimus), and Vitamin A derivatives (such as tazarotene).

Light Therapy and Systemic Medications

For more extensive cases, UV light therapy and systemic medications are often required. Light therapies, including UVA or UVB rays, are typically used in conjunction with other treatments. Due to potential risks of increased skin cancer, regular skin examinations are advised.

Systemic medications, which include oral treatments or injections, are reserved for severe psoriasis cases. Oral options include methotrexate, cyclosporine, retinoids, antimalarials, penicillamine, sulfasalazine, etanercept, infliximab, and adalimumab. Intramuscular gold injections are also utilized.

Non-Medical Treatments

Non-medical interventions, such as physiotherapy, exercise, hydrotherapy, and thermotherapy, can help alleviate pain and swelling while maintaining and improving joint function.

Written by: Vanora D’Sa MD

References

Langley, Richard. (2010). Psoriasis: Second Edition. Toronto Ontario: Key Porter Books Ltd.

Papp, Kim Alexander., Lass, Jenny. (2011). The Canadian Guide to Psoriasis. Mississauga, Ontario: John Wiley and Sons Canada, Ltd.