Diseases & Conditions



Diseases & Conditions

What is psoriasis?

Psoriasis is a common, chronic inflammatory disease that causes the skin to become swollen and reddened. It is characterized by a cell turnover in which cells build-up rapidly in the skin and slowly rises to the surface forming thick patches called plaques that can itch or feel sore. These plaques can be found on the elbows, knees, legs, back, face, palms, feet, fingernails, toenails, genitals and inside the mouth.


Worldwide, approximately 125 million people have the disease. In the United States, approximately 2% of the population is affected.1 Reports on psoriasis from the Arab world are scarce. A study from the Kingdom of Saudi Arabia showed that the prevalence and clinical features of psoriasis in Saudi patients were similar to those reported from other parts of the world.2


Who gets psoriasis?

The disease occurs equally in men and women. Although psoriasis can happen at any age, it is more common in people between 15 and 30 years of age and then later in life between 50 and 60 years of age.3

What causes psoriasis?

The exact cause of psoriasis remains unknown, but it is thought that the immune system plays a major role in the onset of the disease. Although the immune system is supposed to serve as the body’s guard against illness, sometimes it does not function as it is supposed to be. Psoriasis begins when a type of white blood cells called T-cells from the immune system start to attack healthy skin cells by mistake. This attack starts a number of events that makes skin cells multiply too quickly and results in their accumulation on the surface of the skin. It consists of 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 external layer of the skin very fast. Skin cells and white blood cells cannot be removed quickly enough from the skin resulting in the build-up of thick scaly plaques on the surface of the skin. What causes the immune system T-cells to go awry in people with psoriasis is not entirely clear. Genetic causes along with environmental triggers have been found to be the culprit in the development of this disease.4

What are the risk factors of psoriasis?

Although, the cause of psoriasis is not fully understood, certain factors and triggers can render a person more likely to develop the disease:5

  • Family history: Psoriasis occurs more frequently in some families suggesting that it could be inherited. Apparently, some factors can trigger psoriasis in genetically predisposed individuals.
  • Microbial infections: Streptococcal infections precede the development or worsening of psoriasis.

Usually psoriasis is triggered by:5

  • Medications: Certain medications may cause or aggravate the psoriasis. The most common agents that cause psoriasis are β-blockers for the treatment of hypertension, lithium for the treatment of bipolar disorder, medications for malaria and some non-steroidal anti-inflammatory drugs.
  • Skin injury: People who suffer injury to the skin may develop psoriasis.
  • Stress, smoking, unhealthy diet, obesity, type 2 diabetes mellitus and metabolic syndrome increase the risk for developing psoriasis.

What are the symptoms of psoriasis?

Psoriasis signs and symptoms can vary from person to person by may include one or more of the following:6

  • Red plaques on the skin covered with silvery scales
  • Small scaling spots (mostly observed in children)
  • Area of skin that are dry and cracked that may bleed
  • Itching, burning or sore skin
  • Nails abnormalities, such as thickened, pitted or ridged nails
  • Joint pain, swelling or stiffness

It is important to note that most types of psoriasis go through cycles, developing for few weeks or months, then subsiding for a time or even going into complete remission.

How is psoriasis diagnosed?

To diagnose psoriasis, a dermatologist will perform:7

  • Physical exam and medical history: The dermatologist examines the patient’s skin, nails, and scalp for signs of psoriasis, asks whether family members have psoriasis, and learn about the patient’s life, if he has been under a lot of stress or taking any medicine.
  • Skin biopsy: The dermatologist removes a bit of skin and observes it under a microscope. This is how he can confirm if a person has psoriasis.


How is psoriasis treated?

Currently, several treatments are available to help control psoriasis. Medical therapies along with lifestyle changes help improve the condition. It is important to note that all treatments do not work the same for everyone. Doctors may change treatments if one medication does not work or if the patient develops a bad reaction toward a certain drug.

Common medications include:8

  • Topical treatment
    • Corticosteroids, which help to relieve the swelling
    • Vitamin D analogs, which slow down the growth of skin cells especially in nail psoriasis
    • Anthralin, which helps to normalize skin cell activity and make skin smoother
    • Topical retinoids, which also normalize skin cell activity and may relieve swelling
    • Calcineurin inhibitors, which interfere with T-cell activity, resulting in a decrease in swelling and lesion buildup on the skin
    • Salicylic acid, which aids in promoting removal of dead skin cells and reduces scaling of lesions
    • Coal tar, which reduces swelling, itching and scaling


  • Systemic treatment
    • Nonsteroidal anti-inflammatory drugs which help relieve swelling in joints
    • Disease-modifying drugs, which suppress the immune system to slow down the disease process
    • Biologic response modifiers, which target parts of the immune system to prevent joint destruction


  • Light therapy
    • Natural ultraviolet light from the sun showed marked improvement in treating psoriasis
    • Artificial ultraviolet light


  • Combination therapy
    • Combining the three treatment options (topical, systemic and light treatment) can often yield to better results.




  1. Langley, R. G. B., G. G. Krueger, and C. E. M. Griffiths. "Psoriasis: epidemiology, clinical features, and quality of life." Annals of the rheumatic diseases 64.suppl 2 (2005): ii18-ii23.
  2. Fatani, Mohamad I., Magdy H. Abdulghani, and Khalid A. Al-Afif. "Psoriasis in the eastern Saudi Arabia." Saudi medical journal 23.2 (2002): 213-217.
  3. Excellence in Dermatology™ Excellence in Dermatologic Surgery™ Excellence in Medical Dermatology™ Excellence in Dermatopathology™ (Psoriasis: Who gets and causes)
  4. Psoriasis (Causes). http://www.mayoclinic.org/diseases-conditions/psoriasis/basics/causes/con-20030838
  5. Coimbra, Susana, et al. Psoriasis: Epidemiology, Clinical and Histological Features, Triggering Factors, Assessment of Severity and Psychosocial Aspects. INTECH Open Access Publisher, 2012.
  6. Psoriasis (Symptoms). http://www.mayoclinic.org/diseases-conditions/psoriasis/basics/symptoms/con-20030838
  7. Plaque Psoriasis (: Practice Essentials, Overview, Pathophysiology). http://emedicine.medscape.com/article/1108072-overview
  8. Handa, Sanjeev. "Newer trends in the management of psoriasis at difficult to treat locations: scalp, palmoplantar disease and nails." Indian Journal of Dermatology, Venereology, and Leprology 76.6 (2010): 634.