The causes of skin lesions with psoriatic plaques are not fully established. The majority of doctors consider genetic predisposition to be the main factor in the development of pathology. Psoriasis is a systemic, non-infectious, chronic, relapsing 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. In psoriasis, this process takes no more than 5 days.
Externally, this is manifested by the formation on the skin of dense areas of red or pink color, covered with small white scales of dead cells. If carefully scraped, a thin shiny film (terminal) with a clearly visible network of capillaries will be found. After a light rub on it, drops of blood appear.
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 provoking the appearance of psoriasis are considered to be:
- Exogenous (external causes). These include various skin injuries of a physical or chemical nature.
- Endogenous (internal causes). They can 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 nervous shocks or prolonged emotional overstrain.
Skin rashes are often the result 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 the factors that provoke it.
Forms of psoriasis
This or that form of the disease depends on the type of rash and the place of their localization. During pregnancy, due to changes in the hormonal background, psoriatic manifestations may disappear or, on the contrary, appear with greater force.
psoriasis vulgaris
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 increase and gradually merge with each other.
Depending on the form of the rashes, ordinary psoriasis is divided into:
- punctate (papules in the form of a point the size of a matchhead);
- teardrops (oblong spots the size of a pin head);
- coin-shaped (pea-sized round plaques).
Rashes can be in the form of a rainbow, a circle, a spiral, a garland. Sometimes they resemble the outlines of continents on a geographical map. If the disease is localized on the scalp, then they talk about seborrheic type psoriasis. 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 borders of the affected areas, the presence of the "psoriatic triad", the silvery color of the scales. There is often itching, 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. Psoriasis of the nails changes their color, shape and structure. They loosen, become covered with small depressions and acquire the shape of a thimble.
Isolation of exudate from the papules causes a burning sensation. The scales stick together and form a crust that tightly adheres to the skin. In this case, they speak of an exudative form of psoriasis.
In severe cases, the entire surface of the body is affected. The skin becomes hot to the touch, acquires a red hue, swells, has severe itching, burning and a feeling of tightness. This form of the disease is classified as psoriatic erythroderma.
Pustular psoriasis
It is quite rare. It develops against the background of vulgar or appears on absolutely healthy skin. In this case, inflamed areas first appear, on which blisters form during the day, which quickly turn into pustules. Their contents are sterile and dry out and form crusts when drained.
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 appears on the background of psoriasis vulgaris, then no fusion is observed.
Arthropathic psoriasis
It affects joints, most often small ones (phalanges of the fingers and toes). Sometimes the pathological process affects the spine. This form of psoriasis often leads to damage.
The first signs of the disease are pain that increases with movement and swelling of the joints. Evening fever, disruption of the gastrointestinal tract, loss of appetite are characteristic of an exacerbation of the disease.
Over time, there is joint deformation and loss of mobility. The pathology can develop independently or in parallel with the skin manifestations of psoriasis vulgaris.
All forms of pathology can develop gradually, over years, or quickly over several days and even hours. The treatment scheme depends on the form and degree of the disease and must be drawn up by a specialist dermatologist.
External agents in the form of ointments and gels and physiotherapy are most often prescribed. In some cases, drug therapy is necessary. Self-medication can lead to an exacerbation of the disease.