The etiology of psoriasis, one of the most common chronic skin diseases, is still unclear. The pathogenesis of psoriasis is complex. The course of the disease is undulating, with variable periods of remission and relapses. Among scientists, the prevailing opinion is that psoriasis belongs to the group of systemic diseases of a multifactorial nature, an important role in the occurrence of which is played by hereditary and external factors.
The etiology of psoriasis and the nature of its development are so incomprehensible that great attention has long been paid to the study of the disease. The choice of tactics for treating psoriasis directly depends on the identified causes of its occurrence, the form of the disease, the degree of development, and the severity of symptoms.
Currently, there are several theories of the onset of psoriatic dermatosis. Let’s consider them in more detail.
All diseases “from the nerves”
The theory is neurogenic. Functional disorders of the nervous system are reflected in the development of dermatoses. The fact of the onset of psoriasis after physical and mental trauma, contusion and burns has been proven. In addition, the etiology of psoriasis of a neurogenic nature is confirmed by the therapeutic effect of the use of medications, the action of which is aimed at normalizing the functioning of the autonomic and central nervous system.
Disturbances of the nervous system in patients with psoriasis can also be of a secondary nature, but in any case they negatively affect the development of the disease, increase the frequency of relapses, and create certain difficulties in treatment.
Endocrine theory. Scientists have found some connection between the functions of the gonads and periods of exacerbation of psoriasis. This is most noticeable in women, when the disease begins to progress during menstruation, may subside during pregnancy, and then worsen again during breastfeeding. However, what kind of hormone, the functions of which gland affect the pathogenesis of psoriasis, it was not possible to thoroughly find out.
Exchange theory. Long-term observations of patients have led to the conclusion that there are metabolic factors in the etiology of psoriasis . So patients have a whole “set” of metabolic disorders, low body temperature, changes in protein metabolism, increased cholesterol and total lipids. Together, these changes affect the condition of the skin and contribute to the onset of the primary manifestations of skin disease. In addition, in patients with psoriasis, the metabolism of vitamins is disturbed, there is a noticeable lack of vitamin C, A , B6 and B12, the content of copper, iron, zinc is reduced, which significantly reduces the body’s defense mechanisms.
And the positive therapeutic effect of a fat-free diet, which patients follow, confirms the theory of the influence of metabolic disorders on the occurrence of psoriasis.
And maybe not only?
The theory is parasitic and infectious. Scientists have been trying to find a single causative agent of psoriasis for a long time, for which numerous studies have been carried out. In the 19th century, it was allegedly possible to discover a certain parasitic fungus, which is the causative agent of psoriasis. However, this version was not further confirmed.
The influence of infectious diseases on the occurrence and course of psoriasis, on the contrary, takes place. So, most of the patients seek medical help in the spring-autumn period, when the incidence of colds is most common. It has been proven that psoriasis can manifest itself (relapse of the disease occurs) after a sore throat, flu, catarrh of the upper respiratory tract. Most often, psoriasis is accompanied by chronic tonsillitis (90%). According to scientists, infectious diseases weaken a person’s immunity, affect the state of his vegetative system, which ultimately affects the course of skin diseases.
In addition to the theories of the onset of psoriasis given in the article, there are several more reasonable or only hypothetical versions of the onset of psoriasis. So genetic predisposition is called one of the main causes of this dermatosis, allergic reactivity is also put forward as one of the theories of the onset of the development of the disease, the immunological version is also considered in the study of the etiology of psoriasis. However, none of the theories has yet been fully proven.