Psoriasis is a very troublesome skin disease. It is usually not life-threatening, but its chronic course and resistance to therapy make it a quite unpleasant condition.


Psoriasis is an autoimmune disease. Autoimmune diseases are related to aggressive immune reactions against our own body tissues and organs. In this case, the target tissue is skin and its damage causes the symptoms of psoriasis. The disease has a relationship with genetics and many patients have a positive family history. The condition worsens when the patient is exposed to stress, during infections (usually in viral upper respiratory tract infections) and in hormonal changes in women (menopause, pregnancy).


The psoriasis has variable symptoms and the course of the disease is very individual. It can occur anywhere on the skin such as in hair, on the trunk, palms, elbows, back of the hand, etc.  Its lesions usually look like reddish area covered with keratin scales of dry skin. When peeled, the skin underneath the scales tends to bleed. The presence of scales is caused by autoimmune inflammation, which accelerates keratinization of the affected skin. The inflammation may affect not only skin but also joints causing their pain, redness and stiffness.


Severe cases of psoriasis may attack large skin areas. The skin is red, inflamed and it looses its attributes, especially its barrier function. Bacteria can easily penetrate the damaged skin and the patient can loose body fluid through the defective skin layer.


Psoriasis may be accompanied with other autoimmune diseases, for example with Crohn's disease and ulcerative colitis.


Psoriasis is usually diagnosed by a dermatologist due to its skin manifestation. When there is uncertainty of the lesion origin, it is possible to remove a tissue sample (biopsy) and send it for a histological examination, which confirms the diagnosis.


Prevention of the disease is not possible. However, once the diagnosis is confirmed, it is possible to prevent worsening of the condition by avoiding the above mentioned aggravating factors (see Causes).


The therapy is usually only local. It is necessary to keep sufficient skin care (avoiding skin damage, increased skin hygiene, etc.). As basic medication, we use ointments with substances softening the cornified lesions (acetylsalicylic acid and its derivatives) and local anti-inflammatory agents. Corticosteroids have an excellent short-time effect but they should not be used for a long timed as they may cause serious skin damage as their side effect. It was also proven that irradiation of the skin by ultraviolet rays eases the symptoms but on the other hand, it may increase the risk of melanoma. The most effective (and expensive) therapy is the biological treatment. It is reserved only for the most severe cases of psoriasis where the basic treatment is not sufficient. In the issue of autoimmune diseases, the term "biological treatment" means application of special substances that selectively block some aspects of the immune system suppressing its autoimmune effects.


Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Sources: basic text sources