Psoriasis is a condition in which the human immune system mistakenly attacks healthy skin cells. As a result, scaly plaques 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 red, scaly patches to appear on the surface of the skin. They are often called plaques.
Psoriasis cannot be infected – it is an autoimmune disease and not infectious.
Psoriasis manifests itself as inflammation of the skin, as well as abnormally 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 several times and occurs on average in 3-4 days.
In addition to skin lesions, the disease causes inflammation of the joints (in around 30% of cases). Slightly less often - in 10% of cases - psoriasis leads to inflammation of the uvea (uveitis).
Prevalence of psoriasis
Psoriasis most often affects people aged 15 to 35, but in general, the disease can appear at any age. The first peak of appearance of the pathology occurs between 15 and 20 years, the second between 55 and 60 years.
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, 000 inhabitants.
Types of psoriasis
Like many chronic diseases, psoriasis is distinguished by its stages, severity and form of manifestation.
By step
Psoriasis has three stages: the progressive stage, the stationary stage, and the regression (remission) stage.
INprogressive stagered spots appear on the skin. When merging, they form large scaly plaques with a pronounced red outline at the edges - this is called erythema erythematosus Redness on the skin caused by dilation of capillaries and blood flow. corolla, or corolla. The new patches are very itchy and can be painful.
Traumatized areas of the skin are particularly sensitive to the appearance of new spots: a psoriatic plaque can quickly develop at a place of friction (for example on clothing), as well as at the level of a scratch or ascratch. Doctors call this phenomenon 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 traumatized places, for example after scratches, injections or bruises.
Stationary scene- stabilization phase. The plaques stop growing, but continue to bother and flake. New rashes and spots usually do not appear.
Regression stepoccurs when the symptoms of psoriasis begin to disappear. The desquamation disappears, the plaques lighten and flatten. Symptoms diminish during this phase.
By gravity
To assess the severity of psoriasis, doctors use the Psoriasis Area and Severity Index (PASI) system, an index to assess the severity and prevalence of psoriasis. This requires professional analysis of parameters such as severity of erythema, infiltration, scaling, 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 picture of manifestations, several main forms of psoriasis are distinguished: vulgar, inverse, seborrheic, exudative, droplet, pustular, psoriasis of the palms and soles and psoriatic erythroderma.
Psoriasis vulgaris (ordinary)- one of the most common forms, accounting for approximately 90% of all cases of the disease. First of all, red spots appear on the skin, which within a few days turn into convex, scaly plaques. As the plaques grow, they coalesce into large, scaly, itchy lesions. Then, the disease enters a phase of stabilization and regression: the manifestations of the disease temporarily disappear and the person's well-being improves.
The most common places where psoriasis vulgaris appears are the extensor (external) part of the skin on the elbows and knees. Lesions also appear on the body and scalp.
Psoriasis vulgaris on the outer part of the elbow
Inverse ("reversed") psoriasistakes place in the same way as usual. The only difference lies in the location of the lesions: they do not appear on the extensor (external) part of the knees and elbows, but on the flexor (internal) part, that is to say under the knee, under thearmpits and at the elbow. area, as well as in the neck, eyelids, navel, inguinal folds. The skin in these places is more delicate, moist and rubs against clothing more often. For this reason, the itching may be more severe than in the usual form of the disease, but the peeling in these places is less pronounced.
Seborrheic psoriasisproceeds in the same way as usual, but its foci are located in places with a large number of glands that secrete sebum. These are the scalp, folds behind the ear, cheeks and nasolabial area of the face, forehead, chest and back (mainly the upper part).
Seborrheic psoriasis of the scalp
Exudative psoriasis- a type of disease in which, in addition to peeling, exudate also appears in the lesion. It is a liquid containing proteins, 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, grayish-yellow and sometimes slightly moist. This type of psoriasis appears most often in people with endocrine disorders: thyroid pathologies, type 2 diabetes mellitus or obesity.
Guttate psoriasisIt appears not in the form of plaques on the skin, but in the form of numerous papules - swollen spots of bright red color with peeling in the center. The size of the papules 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 a little better than other types of psoriasis, but in some cases it can turn into an ordinary (vulgar) form.
Pustular psoriasischaracterized by the appearance of multiple pustules on an erythematous red background. Pustules are formations that closely resemble pimples. Such psoriasis can be a consequence of infectious diseases, stress, hormonal imbalance, improper use of medications or inadequate use of ointments. Initially, numerous pustules appear on the red spots. They then coalesce 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 may 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 distort the nails: they become thicker, cloudy and uneven.
Psoriasis on the palm
Erythrodermic psoriasisIt is quite rare and is considered an extremely serious form of the disease. There is redness 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 exacerbation of another form of the disease due to improper treatment or adverse environmental factors (for example, sunburn in advanced psoriasis vulgaris, improper use ofexternal irritant agents or intravenous administration of glucocorticosteroids).
Symptoms of psoriasis
The manifestations of psoriasis vary depending on the type of disease and its severity.
Common symptoms and signs of psoriasis:
- red, raised, scaly patches on the skin;
- itching in the area of inflammation and peeling;
- changes in the nails: point imprints, thickening and crumbling of the plate, its separation;
- joint pain (sometimes).
For an accurate diagnosis, you should contact a specialized specialist - a dermatologist.
The mechanism of development of psoriasis
Psoriasis is an autoimmune disease.
All autoimmune pathologies are associated with dysfunction of the immune system. Normally, it "scans" the body 24 hours a day and looks for disease-causing cells using foreign protein molecules that distinguish them from "normal" cells inherent 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 break down. As a result, the immune system begins to attack healthy cells of individual organs or tissues, causes inflammation in their location and in every possible way harms 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 "fixes" them to skin cells. Having reached the target, T lymphocytes release substances that cause inflammation - cytokines. They cause the first symptoms: redness, swelling, itching and pain.
With psoriasis, skin cells divide several times faster, leading to flaking and flaking.
Under the influence of cytokines, an inflammatory process develops and skin cells begin to actively divide - this is how active peeling occurs and a convex plaque is formed.
As the cell renewal process increases almost tenfold, the main cells of the epidermis (keratinocytes) do not have time to form correctly. And therefore, they cannot ensure their barrier function.
As a result, the stratum corneum becomes permeable and ceases to protect the deeper layers of the skin from the environment and moisture loss. All of this leads to even more inflammation.
Until the immune system calms down, the disease will progress and 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 associated with genetics, as well as lifestyle, concomitant diseases and unfavorable environmental factors.
Genetic
The disease is often transmitted from parents to children. Psoriasis is mainly associated with the HLA-C gene. It codes for a protein that allows the immune system to recognize its own (harmless) cells.
In patients with psoriasis, doctors more often than in other people detect a special genetic marker in the HLA-C gene - HLA-Cw6. However, its presence only indicates a predisposition to the disease. Not everyone with the HLA-Cw6 marker has psoriasis, and not all patients diagnosed with the disease have this genetic change.
Lifestyle
It is believed that constant damage to the skin, frequent rubbing, sunburn and hypothermia can be triggers 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 this has a detrimental effect on metabolism, the functioning of internal organs and the immune system.
Concomitant pathologies
Some types of psoriasis, such as guttate psoriasis, can appear after a strep infection.
In addition, the risk of developing pathology is increased 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 is disrupted: it perceives some of its own cells as something foreign, reacts with inflammation and destroys them. As a result, the risk that it will mistakenly add other cells to the "blacklist" increases.
Complications of psoriasis
Psoriasis is caused by immune system dysfunction and chronic systemic inflammation. It develops due to the constant aggression of immune cells towards 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 malfunctions of internal organs. All this is associated with a chronic inflammatory process that affects hormonal levels and interferes with normal metabolism.
Another complication is psoriatic arthritis. This occurs in about 30% of people with psoriasis.
In psoriatic arthritis, the immune system attacks the connective tissue, most often affecting the joints of the lower limbs. Inflammation of the joint structures develops, the skin in the affected area may turn red, swelling appears as well as pain and/or stiffness when trying to bend or straighten the joint.
In 10% of people with psoriasis, the pathology spreads to the eyes and develops uveitis. The choroid of the eye becomes inflamed, leading to decreased vision and discomfort.
In addition to 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 disorder.
Diagnosis of psoriasis
A dermatologist diagnoses skin diseases, including psoriasis.
During the appointment, the doctor will ask you questions about the symptoms and how long ago they appeared. Then, he will question his closest relatives: parents, brothers and sisters about skin diseases. Family history allows a specialist to immediately assume diseases that may be hereditary – psoriasis is one of them.
The doctor will also ask about situations that cause new rashes to appear and symptoms to worsen. For example, new psoriatic lesions may appear after taking a hot bath or prolonged exposure to the sun. In some patients, plaques appear at injection sites, scratches or after rubbing the skin on clothes - this is how the Koebner phenomenon, characteristic of psoriasis, manifests itself.
An important point in establishing a diagnosis is examination of the rash. If the picture of the disease is insufficient, a specialist can observe the rash over time and prescribe a histological examination of the skin (biopsy).
If the doctor is not sure whether the skin plaques are psoriasis, he will order a biopsy and histological examination of the skin.
Histological examination of cutaneous and subcutaneous neoplasms
The study allows us to identify malignant changes in the tissues of skin tumors (moles, papillomas, warts, age spots). For analysis, material obtained by 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. A slight exfoliation of the whitish scales on its surface, or 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 triad - terminal film.
If the doctor continues to scratch the spot, localized bleeding will appear on its surface, called Auspitz syndrome, or bloody dew, the third sign of the psoriatic triad.
After examination and medical history, the doctor will order laboratory tests. It is generally recommended to take a clinical blood test, it reflects the general state of health. The patient is also referred for blood biochemistry. It allows you to assess the functioning of internal organs and metabolism. In the long term, psoriasis can cause 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 analysis includes a physical and chemical examination of the urine (color, density, composition) and a microscopic examination of its sediment. A general urine test is prescribed to check the condition of the body, 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 serious.
Additionally, 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 at an early stage and identify its complications. In the case of an 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 area of affected skin is small, patients are prescribed topical corticosteroid creams or ointments. They suppress inflammation and reduce the manifestations of the disease.
Additionally, the doctor may prescribe local analogues of vitamin A or vitamin D. These 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 moisturizing skin creams from pharmacy dermatocosmetic ranges.
Mild psoriasis is often treated with ointments and creams for external use.
For moderate to severe psoriasis, systemic treatment may be necessary - in the form of conventional immunosuppressive biological drugs and genetically modified in the form of tablets or subcutaneous injections. They have a pronounced effect, but require careful consideration before use.
Systemic glucocorticoids for psoriasis are contraindicated and can only be prescribed by a doctor 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 onto the plaques. Many physiotherapy practices have special lamps for this type of treatment.
The most modern and effective way to treat psoriasis is with monoclonal antibodies (genetically engineered biological therapy). These drugs can block certain stages of the inflammatory response, for example certain cytokines CytokinesProteins, produced mainly by protective cells of the immune system, cause inflammation and plaque growth in psoriasis.
Psoriasis prevention
There is no specific prevention to prevent the development of psoriasis.
In general, it is recommended to lead a healthy lifestyle: give up alcohol and tobacco, exercise and eat a healthy and balanced diet.
People whose loved ones suffer from psoriasis should pay more attention to their skin: moisturize it regularly, avoid hypothermia, prolonged exposure to the sun, and also avoid visiting solariums. Tattoos are not recommended if you have a hereditary predisposition to psoriasis.
Forecast
Psoriasis is a chronic pathology, like all autoimmune diseases. It is impossible to completely cure psoriasis.
However, timely and correctly 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 is an autoimmune disease that 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 hereditary.
How does psoriasis manifest?
In most cases of psoriasis, large, red, scaly patches appear on the surface of the skin. They can be very itchy and even painful. Most often, psoriatic spots appear on the elbows, knees, torso and scalp.
Which doctor treats psoriasis?
A dermatologist treats psoriasis.
Can people with psoriasis be accepted into the military?
With a mild form of psoriasis, they can be classified as category B - "poorly adapted". A conscript 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.