Psoriasis is a pathology in which the human immune system mistakenly attacks healthy skin cells. As a result, wrinkled plates appear on its surface, which can be very itchy and even painful. Sometimes the disease is also accompanied by inflammation of the joints and eyes.
What is psoriasis?
Psoriasis is a chronic autoimmune disease that causes the appearance of red, scaly patches on the surface of the skin. They are often called plaques.
Psoriasis cannot be infected - it is an autoimmune disease, not infectious.
Psoriasis is manifested by inflammation of the skin, as well as by abnormal rapid growth and exfoliation of the cells (keratinocytes) that make up the stratum corneum - the epidermis. Normally, it is completely renewed within a month, but in people with psoriasis this process is accelerated many times and develops on average in 3-4 days.
In addition to skin damage, the disease causes joint inflammation (in about 30% of cases). A little less often - in 10% of cases - psoriasis leads to inflammation of the uvea (uveitis).
Prevalence of psoriasis
Psoriasis most often affects people aged 15-35, but in general the disease can appear at any age. The first peak of the onset of pathology occurs in 15-20 years, the second in 55-60.
On average, psoriasis affects approximately 1-2% of people worldwide. In our country, according to the clinical recommendations of the Ministry of Health, in 2021 the prevalence of the disease was 243. 7 cases per 100 thousand inhabitants.
Types of psoriasis
Like many chronic diseases, psoriasis is distinguished by stages, severity and form of manifestation.
According to the phase
Psoriasis has three stages: progressive, stationary and regressive stage (remission).
INprogressive phasered spots appear on the skin. Joining together, they form large scaly plaques with a pronounced red outline around the edges - it's called Erythema Erythematosus Redness on the skin caused by the dilation of capillaries and blood flow. corolla, or corolla. New plaques are very itchy and can hurt.
Traumatized areas of the skin are particularly susceptible to the appearance of new spots: a psoriatic plaque can quickly develop in a place of friction (for example, on clothing), as well as in the area of a scratch or scratch. Doctors call this phenomenon the Koebner phenomenon.
This phenomenon, also known as the "isomorphic reaction", was discovered by the German dermatologist Heinrich Koebner in 1872. The doctor noticed that in some patients with psoriasis, new plaques appear on the skin in places of trauma, for example after scratches, injections or bruises.
Stationary phase- stabilization phase. Plaques stop growing, but continue to worry and fall. Redness and new spots usually do not appear.
The regression phaseoccurs when psoriasis symptoms begin to disappear. Peeling goes away, plaques are lightened and flattened. At this stage, the symptoms decrease.
According to severity
To assess the severity of psoriasis, doctors use the PASI system (Psoriasis Area and Severity Index) - an index for assessing the severity and prevalence of psoriasis. It requires a professional analysis of parameters such as severity of erythema, infiltration, peeling and calculation of the skin area affected by rashes.
Depending on the results of the examination, doctors distinguish between mild, moderate and severe degrees of the disease.
According to the form
According to the clinical overview of the manifestations, several main forms of psoriasis are distinguished: vulgar, inverse, seborrheic, exudative, guttate, pustular, psoriasis of the palms and soles and psoriatic erythroderma.
Psoriasis vulgaris (common).- one of the most common forms, accounting for about 90% of all cases of the disease. First, red spots appear on the skin, which in a few days turn into convex, scaly plates. As the plaques develop, they coalesce into large, itchy, scaly lesions. Then the condition enters the phase of stabilization and regression: the manifestations of the disease temporarily recede and the person's well-being improves.
The most common places where psoriasis vulgaris appears are the extensor (outer) skin of the elbows and knees. Lesions also appear on the body and scalp.
Psoriasis vulgaris on the outside of the elbow
Psoriasis inversi ("reverse").continue in the same way as usual. The only difference is in the location of the lesions: they do not appear in the extensor (outer) part of the knees and elbows, but in the flexor (inner) part - that is, under the knee, under the armpit and at the elbow. area, as well as the neck, eyelids, navel, inguinal folds. The skin in these places is more delicate, moist and often rubs against clothes. Because of this, it may itch more than with the usual form of the disease, but the peeling in these places is less pronounced.
Seborrheic psoriasiscontinues in the same way as normal, but its foci are located in places with a large number of glands that secrete sebum. This is the scalp, folds behind the ears, cheeks and nasolabial area of the face, forehead, chest and back (mainly the upper part).
Seborrheic psoriasis on the scalp
Exudative psoriasis- a type of disease in which, in addition to peeling, exudate also appears in the lesion. It is a fluid that contains proteins, some blood cells and other substances. Exudate can be released from capillaries during inflammation.
The crust on the surface of the plaques in the exudative form of the disease is usually dense, yellow to gray and sometimes slightly moist. This type of psoriasis occurs more often in people with endocrine disorders: thyroid pathology, diabetes mellitus type 2 or obesity.
Pharyngeal psoriasisIt does not appear as plaques on the skin, but as multiple papules - bright red swollen spots with skin in the center. The size of the papule can vary from approximately 1 to 10 mm. They mainly cover the torso, arms and legs.
Guttate psoriasis usually occurs in children after streptococcal infections (for example, tonsillitis). It is treated somewhat better than other types of psoriasis, but in some cases it can return to the usual (vulgar) form.
Pustular psoriasischaracterized by the appearance of numerous pustules on a red erythematous background. Pustules are formations that look very similar to pimples. Such psoriasis can be a consequence of infectious diseases, stress, hormonal imbalance, improper use of medicines or inadequate use of ointments. Initially, numerous pustules appear on the red spots. They then merge into a large purulent spot (or "purulent lake").
The generalized form of pustular psoriasis is difficult to tolerate: with episodes of fever, weakness, as well as severe pain and burning of the skin. At the same time, changes in the nails and pain in the joints can be observed.
Psoriasis of the palms and soles- Typical psoriatic rashes appear on the palms and soles, less often they appear in the form of localized pustular psoriasis. It can also affect and deform the nails - they become thicker, cloudy and uneven.
Psoriasis on palm
Erythrodermic psoriasisIt is quite rare and is considered an extremely severe form of the disease. There is a rash on about 90% of the body, itching and severe pain appear, the skin swells and peels. The temperature often rises and the lymph nodes become inflamed.
Typically, this type of psoriasis is the result of an aggravation of another form of the disease due to improper treatment or negative environmental factors (for example, sunburn in advanced psoriasis vulgaris, inadequate use of external irritant agents or administrationintravenous glucocorticosteroids).
Symptoms of psoriasis
Manifestations of psoriasis vary depending on the type of disease and its severity.
Common symptoms and signs of psoriasis:
- red, raised, scaly spots on the skin;
- itching in the area of inflammation and skin;
- changes in the nails: precise impressions, thickening and crumbling of the plate, its separation;
- joint pain (sometimes).
For an accurate diagnosis, you should contact a specialized specialist - a dermatologist.
Mechanism of development of psoriasis
Psoriasis is an autoimmune disease.
All autoimmune pathologies are associated with an error in the functioning of the immune system. Normally, it "scans" the body around the clock and looks for pathogenic cells by foreign protein molecules that distinguish them from the "normal" cells naturally found in the body.
As soon as foreign protein molecules are detected, the immune system activates special immune cells - T lymphocytes, which must destroy the enemy.
But for some people, the friend-foe recognition system can be broken. As a result, the immune system begins to attack healthy cells of individual organs or tissues, provokes inflammation in their location and in every possible way damages its body, which, in fact, it should protect.
This is what happens with psoriasis: the immune system attacks the skin. It activates T lymphocytes and "places" them in the skin cells. Having reached the target, T lymphocytes release substances that cause inflammation - cytokines. They provoke the first symptoms: redness, swelling, itching and pain.
With psoriasis, skin cells divide several times faster, resulting in scales and melting.
Under the influence of cytokines, an inflammatory process develops and skin cells begin to divide actively - this is how active peeling occurs and a convex plate is formed.
Since the process of cell renewal is accelerated almost tenfold, the main cells of the epidermis (keratinocytes) do not have time to form properly. Therefore, they cannot perform their barrier function.
As a result, the stratum corneum becomes permeable and ceases to protect the deep layers of the skin from the environment and moisture loss. All this leads to even greater inflammation.
Until the immune system calms down, the disease will progress and the symptoms will increase.
Causes of psoriasis
The exact reasons why psoriasis develops are not yet fully understood. However, many studies agree that the development of psoriasis is related to genetics, as well as lifestyle, comorbidities, and adverse environmental factors.
Genetics
The disease is often inherited from parents to children. Psoriasis is mainly related to the HLA-C gene. It encodes a protein that allows the immune system to recognize its own (harmless) cells.
In patients with psoriasis, doctors detect a special genetic marker in the HLA-C gene more often than in other people - HLA-Cw6. However, its presence only indicates a predisposition to the disease. Not all people with the HLA-Cw6 marker necessarily have psoriasis, and not all patients diagnosed with the disease have this genetic change.
Way of life
It is believed that continuous damage to the skin, frequent rubbing, sunburn and hypothermia can be the cause for the development of the disease. Especially if there is a hereditary predisposition in the form of the genetic marker HLA-Cw6 or close relatives suffering from psoriasis.
Other risk factors include constant stress, alcohol abuse and smoking - all of this has a detrimental effect on metabolism, the functioning of internal organs and the immune system.
Associated pathologies
Some types of psoriasis, such as guttate psoriasis, can appear after a streptococcal infection.
Also, the risk of developing pathology increases in people with autoimmune diseases. These include, for example, type 1 diabetes, Crohn's disease, systemic lupus erythematosus and rheumatoid arthritis.
In such diseases, the general mechanism of the immune system breaks down: it perceives some of its own cells as something foreign, reacts with inflammation and destroys them. Therefore, the risk of it mistakenly adding other cells to the "black list" increases.
Complications of psoriasis
Psoriasis is caused by a dysfunction of the immune system and chronic systemic inflammation. It develops due to the constant aggression of immune cells against healthy tissues.
Autoimmune processes are distinguished by the fact that they can spread: the immune system is able to include other healthy cells in the list of "enemies" at any time.
For example, against the background of psoriasis, Crohn's disease or ulcerative colitis can develop if the immune system mistakenly attacks the tissues of the gastrointestinal tract.
In addition to autoimmune diseases, people with psoriasis are susceptible to various endocrine pathologies (metabolic syndrome, obesity, type 2 diabetes), cardiovascular diseases (hypertension, heart attack) and other internal organ dysfunctions. All this is associated with a chronic inflammatory process, which affects hormonal levels and interferes with normal metabolism.
A particular complication is psoriatic arthritis. It occurs in approximately 30% of people with psoriasis.
In psoriatic arthritis, the immune system attacks the connective tissue, most often affecting the joints of the lower extremities. Inflammation of the joint structures develops, the skin in the affected area may become red, swelling appears, as well as pain and/or stiffness when you try to bend or straighten the joint.
In 10% of people with psoriasis, the pathology spreads to the eye and develops uveitis. The choroid of the eye becomes inflamed, which leads to reduced vision and discomfort.
In addition to the physiological complications, psoriasis can affect a person's mental health. Changes in appearance, poor skin condition and unbearable itching can cause self-doubt and lead to depressive disorders.
Diagnosis of psoriasis
A dermatologist diagnoses skin conditions, including psoriasis.
At the appointment, the doctor will ask about the symptoms and how long ago they appeared. Then he will ask his closest relatives: parents, brothers and sisters about skin diseases. Family history allows a specialist to immediately assume diseases that can be inherited - psoriasis is one of them.
The doctor will also ask about the situations that provoke the appearance of new rashes and the worsening of symptoms. For example, new psoriatic lesions may appear after taking a hot shower or prolonged exposure to the sun. In some patients, plaques appear at injection sites, scratches or after rubbing the skin on clothing - this is how the Koebner phenomenon, characteristic of psoriasis, appears.
An important point in establishing a diagnosis is the examination of the rash. If the picture of the disease is insufficient, a specialist can observe the redness over time and prescribe a histological examination of the skin (biopsy).
If the doctor is not sure that the plaques on the skin are psoriasis, he will prescribe a biopsy and histological examination of the skin.
Histological examination of skin and subcutaneous neoplasms
The study allows us to identify malignant changes in the tissues of skin tumors (moles, papillomas, warts, age spots). For analysis, the material obtained through biopsy or during surgery is used.
In some cases, a specialist can check the psoriatic triad, the main diagnostic signs of psoriasis.
First, the dermatologist will take a glass slide or scalpel and begin to gently scrape the surface of the plaque. The slight exfoliation of white scales from its surface, or the stearin stain phenomenon, is the first sign of the triad.
After all the crusts are peeled off, the surface of the plate becomes smooth, shiny and slightly moist. This is the second sign of the triple film - terminal.
If the doctor continues to scratch the spot, accurate bleeding will appear on its surface, which is called Auspitz syndrome, or bloody dew, the third sign of the psoriatic triad.
After an examination and medical history, the doctor will prescribe laboratory tests. It is generally recommended to do a clinical blood test - it reflects the general state of health. The patient is also referred for blood biochemistry. This allows you to evaluate the functioning of internal organs and metabolism - with a long course, psoriasis can provoke pathologies of the cardiovascular and endocrine systems.
A general urine test is also often prescribed. Disorders related to the urinary system may interfere with the prescription of certain medications.
A general urine test includes a physical and chemical examination of urine (color, density, composition) and a microscopic examination of its sediment. A general urine test is prescribed to check the condition of the body, to identify pathologies of the urinary system, gastrointestinal tract, endocrine, infectious and inflammatory diseases.
For the same reason, according to clinical recommendations, tests for HIV and hepatitis are prescribed. Against the background of these infections, the disease can be more severe.
Also, in preparation for treatment, women should take a pregnancy test - for example, take a blood test for beta-hCG. The fact is that many systemic drugs, which are most often prescribed for the treatment of psoriasis and give a good effect, are contraindicated during pregnancy.
The study allows you to diagnose pregnancy in the early stages and identify its complications. In induced abortion, it is used to evaluate the effectiveness of the procedure. In oncology - for the diagnosis of hormone-producing tumors.
If you complain of joint pain, the doctor will also refer the patient for an MRI, CT scan or x-ray to confirm or rule out psoriatic arthritis. If joint inflammation is confirmed, the dermatologist will recommend an examination by a rheumatologist.
Treatment of psoriasis
If the affected skin area is small, patients are prescribed topical corticosteroid creams or ointments. They suppress inflammation and reduce the manifestations of the disease.
In addition, the doctor can prescribe local analogues of vitamin A or vitamin D. Such drugs relieve inflammation, accelerate the exfoliation of the stratum corneum of the skin and slow down the growth of psoriatic plaques. It is also recommended to use skin moisturizers from pharmacy dermatocosmetics lines.
Mild psoriasis is often treated with topical ointments and creams.
For moderate to severe psoriasis, systemic treatment may be required - in the form of classical immunosuppressive biologics and genetically engineered drugs in the form of tablets or subcutaneous injections. They have a pronounced effect, but require careful examination before use.
Systemic glucocorticosteroids for psoriasis are contraindicated and can be prescribed by a doctor only in certain (extremely difficult) situations and in a hospital setting. Otherwise, such treatment can lead to a significant deterioration of the condition.
Psoriasis is also treated with phototherapy: ultraviolet light of a certain spectrum is directed at the plaques. Many physical therapy offices have special lamps for this type of treatment.
The most modern and effective way to treat psoriasis is monoclonal antibodies (biological therapy of genetic engineering). These drugs can block some stages of the inflammatory response, for example, certain cytokines Cytokine Proteins, which are mainly produced by the protective cells of the immune system, provoke inflammation and plaque growth in psoriasis.
Prevention of psoriasis
There is no specific prevention that can prevent the development of psoriasis.
In general, it is recommended to lead a healthy lifestyle: give up alcohol and smoking, exercise and eat a healthy and balanced diet.
People whose relatives have psoriasis should be more careful about their skin: moisturize it regularly, avoid hypothermia, prolonged exposure to the sun, and also avoid visits to solariums. Tattoos are not recommended if you have a hereditary predisposition to psoriasis.
PREDICTION
Psoriasis is a chronic pathology, like all autoimmune diseases. It is impossible to completely cure psoriasis.
However, timely and properly selected treatment can allow the patient to achieve long-term remission - a period of asymptomatic disease.
Frequently asked questions
How is psoriasis transmitted?
Psoriasis cannot be infected. It's an autoimmune disease—it occurs when a person's immune system malfunctions and mistakenly attacks skin cells. The disease has a hereditary (genetic) predisposition, which means that it can be inherited.
How does psoriasis appear?
In most cases of psoriasis, large red, scaly plaques appear on the surface of the skin. They can be very itchy and even painful. Most often, psoriatic patches appear on the elbows, knees, torso and scalp.
Which doctor treats psoriasis?
A dermatologist treats psoriasis.
Can people with psoriasis be accepted into the army?
With a mild form of psoriasis, they can be assigned category B - "limitedly suitable". A recruit with moderate or severe psoriasis may be considered unfit for military service. In each particular case, the decision is made individually during the medical examination.