The causes of skin lesions with psoriatic plaques have not been fully established. The vast majority of doctors consider genetic predisposition a key factor in the development of the pathology. Psoriasis is a systemic, non-infectious, chronic and recurrent disease that mainly affects the skin, nails and joints.
The main signs and causes of psoriasis
Psoriatic disease is characterized by increased reproduction of epidermal cells. Normally, cell division, maturation and death occur within 3-4 weeks. With psoriasis, this process takes no more than 5 days.
Outwardly, this is manifested by the formation on the skin of dense areas of red or pink color, covered with small white scales from dead cells. If they are carefully scraped off, a thin shiny film (terminal) with a clearly visible network of capillaries will be exposed. After a slight rubbing, drops of blood appear on it.
This characteristic is called the "psoriatic triad" and is the main difference between psoriasis and other skin diseases. To confirm the diagnosis, a histological examination of skin particles from the affected areas is performed.
The main factors that provoke the appearance of psoriasis are considered:
- Exogenous (external causes). These include various skin injuries of a physical or chemical nature.
- Endogenous (internal causes). They may consist in the presence of diseases of the immune system, endocrine system, HIV infection. Smoking, alcohol, unhealthy diet also provoke psoriatic skin lesions.
- Psychogenic. In most cases, the first manifestations of psoriasis appear after suffering from nervous shocks or prolonged emotional overload.
Often, rashes are a consequence of infectious and inflammatory diseases. Many doctors attribute this to a weakened immune system. People with a genetic predisposition to psoriasis are advised to avoid triggers.
Forms of psoriatic disease
This or that form of the disease depends on the type of rash and the place of its localization. During pregnancy, due to changes in the hormonal background, psoriatic manifestations may disappear or, on the contrary, manifest themselves with greater force.
vulgar psoriasis
The most common form of pathology. The first signs are papular rashes. They can be single, grouped in different parts or all over the body. As the disease progresses, psoriatic plaques enlarge and gradually fuse together.
Depending on the form of rashes, common psoriasis is divided into:
- punctate (dot-shaped papules the size of a match head);
- drop-shaped (oblong spots the size of a pinhead);
- coin-shaped (pea-sized round plates).
Rashes can be in the form of an arc, circle, spiral, garland. Sometimes they resemble the outlines of continents on a geographic map. If the disease is located on the scalp, then they talk about psoriasis of the seborrheic type. Sometimes the neck, nose, forehead and chest are affected. The diagnosis is difficult due to the similarity of the pathology with seborrhea.
Distinctive features are the clarity of the boundaries of the affected areas, the presence of the "psoriatic triad", the silvery color of the scales. There is often itching, the hair does not fall out.
The clustering of plaques on the feet and hands has given the name palmoplantar psoriasis. It is characterized by the formation of polished areas of the skin, resembling calluses. Nail psoriasis changes color, shape and structure. They come off, become covered with small depressions and take the form of a thimble.
Isolation of exudate from the papules causes a burning sensation. The scales stick together and form a scab that adheres tightly to the skin. In this case, they talk about the exudative form of psoriasis.
In severe cases, the entire body surface is affected. The skin becomes hot to the touch, acquires a red tint, swells, there is severe itching, burning and a feeling of tightness. This form of the disease is classified as psoriatic erythroderma.
pustular psoriasis
It occurs very rarely. It develops against the background of vulgar or appears on absolutely healthy skin. In this case, inflamed areas appear first, on which blisters form during the day, quickly turning into pustules. Its contents are sterile and, when drained, dry and form crusts.
There are several types of the disease. All of them are characterized by chills, fever, fever, sometimes diarrhea, vomiting. The condition worsens when the pustules merge and occupy large areas of the skin. If pustular psoriasis occurs against the background of vulgar psoriasis, then no fusion is observed.
arthropathic psoriasis
It affects the joints, most often small (phalanges of the fingers and toes). Sometimes the pathological process affects the spine. This form of psoriasis often leads to disability.
The first signs of the disease are pain, aggravated by movement, and swelling in the joints. Night fever, disturbance of the gastrointestinal tract and loss of appetite are characteristic of an exacerbation of the disease.
Over time, there is joint deformity and loss of mobility. The pathology can develop independently or in parallel with the cutaneous manifestations of psoriasis vulgaris.
All forms of pathology can develop gradually, over years, or rapidly over several days and even hours. The treatment regimen depends on the form and degree of the disease and should be worked out by a specialist dermatologist.
Most often, external agents are prescribed in the form of ointments and gels and physiotherapy. In some cases, drug therapy is required. Self-medication can lead to an exacerbation of the disease.