Psoriasis is a disease in which the human immune system mistakenly attacks healthy skin cells. This causes scaly plaques to form on its surface, which can be very itchy and even painful. Sometimes the disease is accompanied by inflammation of the joints and eyes.
What is Psoriasis?
Psoriasis is a chronic autoimmune disease that causes red, scaly patches to form on the surface of the skin. They are often referred to as plaques.
Psoriasis cannot be infected - it is an autoimmune disease and not an infectious disease.
Psoriasis is characterized by inflammation of the skin and unusually rapid growth and shedding of cells (keratinocytes) that make up the stratum corneum - the epidermis. Usually 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 damage, the disease leads to joint inflammation (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 commonly affects people between the ages of 15 and 35, but in general the disease can occur at any age. The first peak of the onset of pathology occurs at the age of 15-20, the second at the age of 55-60.
On average, psoriasis affects about 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 differentiated according to stages, severity and form of manifestation.
Bit by bit
Psoriasis has three stages: progressive, stationary and regression (remission).
INprogressive stageRed spots appear on the skin. When they merge, they form large scaly plaques with pronounced red outlines at the edges - this is called erythematous erythema. Redness of the skin caused by dilation of capillaries and blood flow. crown or crown. New plaques are very itchy and can be painful.
Traumatized areas of skin are particularly susceptible to the formation of new spots: a psoriatic plaque can quickly develop at a place of friction (e. g. on clothing), as well as in the area of a scratch or scrape. Doctors call this phenomenon the Koebner phenomenon.
This phenomenon, also called the "isomorphic reaction, " was discovered in 1872 by the German dermatologist Heinrich Koebner. The doctor noticed that in some psoriasis patients, new plaques appeared on the skin in traumatic places, for example after scratches, injections or bruises.
Stationary stage- Stabilization phase. The plaques stop growing but continue to bother and flake off. New rashes and spots usually do not appear.
Regression phaseoccurs when the symptoms of psoriasis begin to disappear. The peeling disappears, the plaques become lighter and flatter. During this phase the symptoms decrease.
By severity
To assess the severity of psoriasis, doctors use the Psoriasis Area and Severity Index (PASI) system, an index for assessing the severity and prevalence of psoriasis. It requires professional analysis of parameters such as the severity of erythema, infiltration, detachment and calculation of the area of skin affected by rashes.
Depending on the results of the examination, doctors differentiate between mild, moderate and severe courses of the disease.
By shape
Depending on the clinical manifestations, several main forms of psoriasis are distinguished: vulgar, inverse, seborrheic, exudative, gutting, pustular psoriasis of the palms and soles, as well as psoriatic erythroderma.
Vulgar (common) psoriasis- one of the most common forms, accounting for about 90% of all cases of the disease. Initially, red spots appear on the skin, which within a few days turn into convex, scaly plaques. 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 subside and the person's well-being improves.
The most common places where psoriasis vulgaris occurs are the extensor muscles (outer part) of the skin of the elbows and knees. Lesions also occur on the body and scalp.
Psoriasis vulgaris on the outer part of the elbow
Inverse ("reverse") psoriasisruns as usual. The only difference is the location of the lesions: they do not occur on the extensor muscle (outer part) of the knees and elbows, but on the flexor part (inner part), i. e. under the knee, under the armpits and in the elbow area, as well as in the neck, Eyelids, navel, groin folds. The skin in these areas is more sensitive, moist and rubs against clothing more often. For this reason, there may be more itching than in the usual form of the disease, but the peeling in these areas is less pronounced.
Seborrheic psoriasisproceeds as normal, but its foci are located in places with a large number of sebaceous glands. 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 on the scalp
Exudative psoriasis- a type of disease in which, in addition to peeling, exudate also appears in the lesion. It is a liquid that contains protein, some blood cells and other substances. In the event of inflammation, exudate can be released from the capillaries.
In the exudative form of the disease, the crust on the surface of the plaques is usually dense, grayish-yellow and sometimes slightly moist. This type of psoriasis most often occurs in people with endocrine disorders: thyroid disease, type 2 diabetes mellitus or obesity.
Guttate psoriasisIt appears not as a plaque on the skin, but as numerous papules - swollen spots of bright red color with a peeling in the center. The size of the papules can vary between about 1 and 10 mm. They mainly cover the torso, arms and legs.
Guttate psoriasis usually occurs in children after streptococcal infections (e. g. tonsillitis). It is slightly more treatable than other types of psoriasis, but in some cases it can progress to the common (vulgar) form.
Pustular psoriasischaracterized by the appearance of multiple pustules on a red, erythematous background. Pustules are structures that look very similar to pimples. Such psoriasis can be a result of infectious diseases, stress, hormonal imbalance, improper medication or insufficient use of ointments. Numerous pustules initially form on the red spots. They then merge to form a large purulent spot (or "purulent lake").
The generalized form of pustular psoriasis is difficult to tolerate: with fever attacks, weakness and 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 psoriasis rashes occur in the area of the palms and soles, less commonly they occur in the form of localized pustular psoriasis. It can also affect and deform nails - making them thicker, cloudy and uneven.
Psoriasis on the palm
Erythrodermic psoriasisIt is quite rare and is considered an extremely severe form of the disease. About 90% of the body is red, severe itching and pain occurs, and 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 unfavorable environmental factors (for example, sunburn in advanced psoriasis vulgaris, insufficient use of irritating external agents, or intravenous administration of glucocorticosteroids).
Symptoms of psoriasis
The manifestations of psoriasis vary depending on the type of disease and 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: punctual impressions, thickening and crumbling of the plate, its detachment;
- Joint pain (sometimes).
For an accurate diagnosis, you need to contact a specialized specialist – a dermatologist.
The mechanism of development of psoriasis
Psoriasis is an autoimmune disease.
All autoimmune diseases are associated with a malfunction of the immune system. Normally, it "scans" the body around the clock and looks for pathogen cells using foreign protein molecules that distinguish them from "normal" body cells.
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-enemy recognition system could break down. As a result, the immune system begins to attack healthy cells of individual organs or tissues, causing inflammation in their places and in every possible way damaging its body, which it was supposed to protect.
Here's what happens with psoriasis: The immune system attacks the skin. It activates T-lymphocytes and "places" them on skin cells. Once they reach their destination, T-lymphocytes release substances that cause inflammation - cytokines. They cause the first symptoms: redness, swelling, itching and pain.
In psoriasis, skin cells divide many times faster, resulting in flakiness 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.
Since the process of cell renewal accelerates almost tenfold, the main cells of the epidermis (keratinocytes) do not have time to form properly. And therefore they cannot fulfill their barrier function.
As a result, the stratum corneum becomes permeable and no longer protects the deeper layers of skin from environmental influences and loss of moisture. All of this leads to even more inflammation.
Until the immune system calms down, the disease progresses and symptoms 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 passed on from parents to children. Psoriasis is primarily 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 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.
lifestyle
It is assumed that constant damage to the skin, frequent friction, sunburn and hypothermia can trigger the development of the disease. Especially if there is a hereditary predisposition in the form of the genetic marker HLA-Cw6 or if close relatives suffer from psoriasis.
Other risk factors include constant stress, alcohol abuse and smoking - all of which have a detrimental effect on metabolism, the function of internal organs and the immune system.
Accompanying pathologies
Some types of psoriasis, such as: B. Guttate psoriasis, can occur after a streptococcal infection.
In addition, the risk of 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. Accordingly, the risk that it will incorrectly add more cells to the "black list" increases.
Complications of psoriasis
Psoriasis is caused by immune system dysfunction and chronic systemic inflammation. It arises due to the constant aggression of immune cells towards healthy tissue.
Autoimmune processes are characterized by the fact that they can spread: the immune system is able to add other healthy cells to the list of "enemies" at any time.
For example, against the background of psoriasis, Crohn's disease or ulcerative colitis can develop when the immune system mistakenly attacks the tissue 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 dysfunctions of internal organs. All this is associated with a chronic inflammatory process that affects hormone levels and disrupts normal metabolism.
A separate complication is psoriatic arthritis. It occurs in about 30% of people with psoriasis.
In psoriatic arthritis, the immune system attacks the connective tissue; the joints of the lower extremities are most commonly affected. Inflammation of the joint structures occurs, the skin in the affected area may become red, swelling occurs, and pain and/or stiffness occur when attempting to flex or straighten the joint.
In 10% of people with psoriasis, the pathology spreads to the eyes and uveitis develops. The choroid of the eye becomes inflamed, causing reduced vision and discomfort.
In addition to physiological complications, psoriasis can also 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.
At the appointment, the doctor will ask about the symptoms and how long they have been occurring. Then he will ask his closest relatives: parents, siblings about skin diseases. Based on the family history, a specialist can immediately assume that diseases can be inherited - psoriasis is one of them.
The doctor will also ask about situations that provoke the appearance of new rashes and worsening of symptoms. For example, new psoriasis lesions may appear after a hot bath or prolonged exposure to the sun. In some patients, plaques appear at injection sites, scratches or after rubbing the skin against clothing - this is how the Köbner phenomenon, which is characteristic of psoriasis, manifests itself.
An important point in making a diagnosis is examining the rash. If the clinical picture is inadequate, a specialist can observe the rash over time and order 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 tissue of skin tumors (moles, papillomas, warts, age spots). Material obtained through a biopsy or during surgery is used for analysis.
In some cases, a specialist may examine the psoriasis triad, the main diagnostic signs of psoriasis.
First, the dermatologist takes a glass slide or a scalpel and begins to gently scrape the surface of the plaque. A slight peeling of whitish scales from the surface or the phenomenon of stearin discoloration is the first sign of the Triassic.
After all crusts have been removed, the surface of the plaque becomes smooth, shiny and slightly moist. This is the second sign of the triad – final film.
If the doctor continues to scratch the area, pinpoint bleeding occurs on the surface, called Auspitz syndrome or bloody dew, which is the third sign of the psoriasis triad.
After an examination and anamnesis, the doctor will prescribe laboratory tests. It is generally recommended that a clinical blood test be carried out - this 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 - with a prolonged course, psoriasis can provoke pathologies of the cardiovascular and endocrine systems.
A general urine test is often prescribed. Diseases of the urinary system may affect 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 and detect pathologies of the urinary system, gastrointestinal tract, endocrine, infectious and inflammatory diseases.
For the same reason, tests for HIV and hepatitis are prescribed according to clinical recommendations. Against the background of these infections, the disease can be more serious.
Women should also take a pregnancy test to prepare for treatment - for example, a blood test for beta-hCG. The fact is that many systemic drugs that are most often prescribed to treat psoriasis and have a good effect are contraindicated during pregnancy.
The study allows you to diagnose pregnancy in the early stages and identify its complications. In artificial abortion, it is used to assess 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 or X-ray scan 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 may prescribe local analogues of vitamin A or vitamin D. Such drugs relieve inflammation, accelerate the shedding of the stratum corneum of the skin and slow down the growth of psoriatic plaques. It is also recommended to use skin moisturizers from the pharmacy's dermatocosmetics line.
Mild psoriasis is often treated with topical ointments and creams.
For moderate to severe psoriasis, systemic treatment may be required - in the form of classic immunosuppressants and genetically modified biological drugs in the form of tablets or subcutaneous injections. They have a pronounced effect, but require careful consideration before use.
Systemic glucocorticosteroids for psoriasis are contraindicated and can only be prescribed by a doctor in certain (extremely difficult) situations and in the hospital. Otherwise, such treatment can lead to a significant deterioration of the condition.
Psoriasis is also treated with phototherapy: ultraviolet light of a specific spectrum is directed at the plaques. Many physical therapy practices have special lights for this type of treatment.
The most modern and effective method for treating psoriasis is monoclonal antibodies (genetic biological therapy). These drugs can block some stages of the inflammatory response, for example certain cytokines, cytokines, proteins produced primarily by the protective cells of the immune system that cause inflammation and plaque growth in psoriasis.
Prevention of psoriasis
There is no specific prevention that could prevent psoriasis from developing.
In general, a healthy lifestyle is recommended: avoid alcohol and smoking, do sports and eat a healthy, balanced diet.
People whose relatives suffer from psoriasis should pay more attention to their skin: moisturize regularly, avoid hypothermia, prolonged exposure to the sun and also visiting solariums. Tattoos are not recommended if you have a hereditary predisposition to psoriasis.
forecast
Like all autoimmune diseases, psoriasis is a chronic pathology. 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 - it occurs when a person's immune system fails and accidentally attacks skin cells. The disease has a hereditary (genetic) predisposition, meaning it can be inherited.
How does psoriasis manifest itself?
In most cases of psoriasis, large red, scaly plaques appear on the surface of the skin. They can be very itchy and even painful. Psoriatic patches most commonly appear on the elbows, knees, trunk and scalp.
Which doctor treats psoriasis?
A dermatologist treats psoriasis.
Can people with psoriasis join the army?
With a mild form of psoriasis, they can be assigned to category B - "conditionally suitable". A conscript with moderate or severe psoriasis can be considered unfit for military service. In individual cases, the decision is made individually as part of the medical examination.