Methods of psoriasis diagnosis: laboratory and instrumental methods

It so happened that the entire human body is covered with a unique multifunctional material - skin, which, along with other organs, performs the functions of breathing, thermoregulation, nutrition and protection of the body. Diseases of this unique organ can lead to various disorders in the work of other organs and systems. But statistics are inexorable, and skin diseases make up 15% of the entire mass of diseases with which people consult a family doctor. At the same time, about 2-4% of them (according to various sources) are psoriasis. And, despite the fact that diagnosing psoriasis for an experienced doctor is not particularly difficult, there are certain nuances that must be taken into account when prescribing and conducting diagnostic studies.

A little about the disease itself

Psoriasis is one of the least studied pathologies in humans. Moreover, disputes are still going on both around the etiology of the disease and around the causes that cause it, not to mention effective methods of treating the disease. So psoriasis is still considered an incurable disease of a controversial nature.

According to the latest research on psoriasis, there are 2 main hypotheses for the development of psoriasis. One of them states that psoriasis is a primary skin disease, which is characterized by a disruption of the normal process of maturation and division of skin cells and excessive growth and reproduction (proliferation) of these cells due to disruption of the epidermis function. The immune response is considered secondary.

Another hypothesis insists on the secondary nature of the pathology, i.e. cell proliferation occurs as an inflammatory reaction caused by a malfunction of the immune system, which begins to perceive “native” cells as foreign bodies.

Animal studies do not allow scientists to settle on one of the versions, since they do not provide the opportunity to reproduce the full picture of the pathology in humans. However, they do provide the opportunity to identify certain risk factors that can provoke the appearance of specific psoriatic symptoms, on the basis of which psoriasis is diagnosed.

Such factors include:

• severe stressful situations experienced by the patient,
• traumatic skin injuries,
• acute and chronic infectious diseases,
• changes in climatic conditions of residence,
• HIV infection,
• taking medications in case of intolerance to their components, causing allergic skin reactions,
• use of certain types of hair and skin cosmetics, household chemicals, etc.

Hormonal imbalances, hereditary predisposition or skin characteristics (thin, dry, sensitive skin is more susceptible to the disease than other types) may play a certain role in the development of the pathology (in the presence of certain triggers indicated above).

But sometimes the appearance and exacerbation of psoriasis occurs without any apparent reason, which baffles scientists. Nevertheless, the disease exists, is quite widespread, and therefore there is a need for its further study and the search for effective methods of diagnosing psoriasis, allowing not only to name the problem itself by its "name", but also to determine the cause that caused the development of the pathological process in order to actively fight the disease in both directions.

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Basic methods of diagnosing psoriasis

It would be untrue to say that psoriasis diagnostics is difficult today. The symptoms of the disease are so obvious that an experienced doctor can easily recognize the disease based on external signs alone.

The main specific symptom of psoriasis is a skin rash. At the beginning of the disease, it looks like small pink seals on the skin with a diameter of about 1-2 mm. A little later, they take the form of tubercles with a bright pink border (growth zone), which are covered with whitish, loose, easily removable scales. The tubercles gradually increase in diameter (grow). Usually, their size ranges from 2-3 to 7-8 cm.

The appearance of specific growths (plaques) occurs due to disturbances in the process of cell formation, when old cells that have not yet died are superimposed on new ones that appear prematurely.

Plaques can grow and unite into groups, forming large affected areas, or remain at the same level for a long time in the form of single specimens.

Most often, other than studying the patient’s complaints and examining the skin with scraping, no other research methods are required.

In this case, laboratory tests of urine, blood and feces serve to prescribe effective treatment for the pathology, taking into account the individual characteristics of the patient's body. But in severe cases of pathology or in the presence of controversial symptoms, various tests will help not only to determine the degree of development of the pathology and differentiate psoriasis from other diseases with similar symptoms, but also to identify concomitant diseases in the patient.

In case of unclear clinical picture of the disease, one of the effective methods of diagnostics of psoriasis is considered to be skin biopsy, when a tiny (about 6 mm) piece of skin is taken for microscopic examination. Such examination aims to exclude other skin pathologies with similar symptoms, as well as histological confirmation of the diagnosis of "psoriasis". Biopsy is usually performed once, but if manifestations of the disease change periodically, a repeated analysis of the skin by a pathologist may be required.

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Clinical diagnostics of psoriasis

Psoriasis, although not characterized by a wide range of symptoms, its manifestations are not always visible. This insidious pathology is characterized by a wave-like course, in which various provoking factors (stress, seasonal changes, etc.) can provoke an exacerbation of the disease, and effective treatment can cause a stable remission for a long period.

The disease is diagnosed mainly by its external manifestations in the form of specific rashes on the skin. But these manifestations can be different at different stages of the development of the pathological process.

Thus, the progressive stage is characterized by the appearance of single or multiple papules with a bright pink border, which tend to grow and merge. Over time, they transform into psoriatic plaques that are slightly raised above healthy skin, which begin to peel and itch painfully.

At the stage of regression of the pathology, the papules (plaques) become flatter, pale, peeling and itching are noticeably reduced. Sometimes the plaques disappear completely, but most often they become barely noticeable due to changes in skin pigmentation at the site of the lesion (dark or light spots).

The stationary stage, or period of remission, is characterized by the absence of new rashes and any changes in the appearance of old ones.

In addition, psoriasis can have different localizations and some differences in symptoms, in connection with which the following types and kinds of the disease are distinguished:

• Common, or vulgar psoriasis, which is considered the most common type of the disease. It appears as silvery-white scaly plaques. Most often it is localized in the area of the knee or elbow joints, but can also appear in other parts of the body (on the hands, soles of the feet, on the head along the hairline, etc.).
• Exudative psoriasis has the same localization, but the surface of the spots is covered with a yellowish crust, from under which blood or light yellow liquid (exudate) may be released. This usually happens against the background of developing diabetes mellitus, obesity and other pathologies of the endocrine system.
• Guttate psoriasis most often appears on the body (especially in the thighs and buttocks) and legs, with the rashes taking the form of red or purple drops. It develops against the background of a streptococcal infection.
• Point psoriasis is diagnosed if the above-described rashes are the size and shape of a pinhead.
• Nummular psoriasis is a larger, round rash that reaches 3-5 mm in diameter.
• Pustular psoriasis is characterized by the formation of pustules in the form of islands of inflammation with purulent contents. Such islands can be located both on the feet or palms, and all over the body. It can be accompanied by an increase in body temperature, weakness, bowel disorder, chills, etc.
• Inverse or fold psoriasis is characterized by the fact that psoriatic rashes are localized mainly in large folds of the body.
• Seborrheic psoriasis is characterized by the location of the rash in the scalp area. In this case, yellowish crusts are observed at the site of the rash. The disease most often develops against the background of existing seborrhea.
• Palmoplantar psoriasis. Its name speaks for itself, outlining the localization of psoriatic rashes.
• Nail psoriasis is a special form of the disease in which the nail plate and the skin underneath are affected. In this case, as with a fungal infection, thickening and destruction of the nail is observed.
• Psoriatic erythroderma is characterized by the appearance of a large number of reddish plaques covered with silvery or yellowish scales. The plaques tend to unite to form large itchy lesions, which are often accompanied by fever and enlarged lymph nodes.
• Psoriatic arthritis (atropaic psoriasis) localized in the area of the joints (phalanges of the fingers, wrists, spine area, etc.). At first, it manifests itself only as skin rashes over the joints, but if there is a predisposition and no effective treatment, the disease can spread to the joints themselves, limiting their mobility.
• An atypical form of psoriasis is diagnosed if the localization of plaques is not typical for this type of psoriasis or there are additional symptoms that are not typical for the disease.

Clinical diagnostics of psoriasis consists of studying the patient's complaints, as well as analyzing the existing symptoms, which may indicate one or another type, as well as the kind of psoriasis. But it is difficult to make a correct diagnosis based only on external examination, although almost all the symptoms, as they say, are obvious.

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Tests for psoriasis

As already mentioned, blood, urine and stool tests for psoriasis do not play a decisive role in making a final diagnosis. However, the doctor can still gain some useful information from the laboratory report.

The most informative test for diagnosing psoriasis is a blood test, especially if the doctor has certain difficulties in making a diagnosis. Three types of blood tests are usually prescribed for psoriasis:

• general or clinical analysis,
• biochemical analysis,
• Blood test for autoantibodies.

Blood analysis is especially effective in cases of progressive psoriasis or its severe stage, since in mild forms of the pathology, changes in the blood composition are practically not observed. Studying the blood composition and the biochemical processes occurring in it will help to identify not only individual types of psoriasis, but also associated diseases:

• A general blood test helps to determine the role of inflammatory, rheumatic and autoimmune factors in the development of pathology, the presence of endocrine and biochemical disorders in the body. It is on the basis of this analysis that psoriasis can be diagnosed, developing against the background of such pathologies as leukocytosis, anemia, diabetes mellitus, etc.
• Studying the rheumatoid factor (the presence of protein in the blood) allows us to differentiate psoriatic disease from rheumatoid arthritis. In the first case, the result will be negative.
• ESR indicators are important for diagnosing such pathologies as psoriatic erythroderma and pustular psoriasis. The above-mentioned pathologies are characterized by changes in the erythrocyte sedimentation rate.
• A slightly elevated urea level may indicate the development of a severe form of psoriasis, causing abnormalities in the functioning of internal organs. If the uric acid content is significantly higher than normal, this indicates the development of gout, and not the manifestations of psoriatic arthritis.
• A biochemical blood test helps determine how the liver and kidneys are functioning, determine the activity of inflammatory and rheumatoid factors, see disturbances in water-salt metabolism, and identify imbalances of microelements.
• Blood analysis for autoantibodies allows to detect in time the unsatisfactory state of the immune system (in particular, the presence of HIV infection and other risk factors), hormonal imbalance. The analysis is carried out to assess the general condition of the patient, as well as to exclude allergic and oncological diseases, to detect various infections in the body.

Clinical urine analysis in psoriasis usually remains unchanged. But with a long-term progressive course of the disease, it can show a change in the water-salt balance due to dehydration.

Stool analysis is carried out solely for the purpose of identifying helminths, which reduce the treatment of any pathology to nothing.

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Instrumental diagnostics of psoriasis

If the above tests do not clarify the problem, for example, in the case of a severe course of the disease or non-specific symptoms, additional methods of diagnosing psoriasis may be required, such as a skin biopsy, microflora culture, testing using potassium oxide, prolactin analysis, and examination for syphilis.

Most often, the matter is limited to a skin biopsy, which reveals: a large number of neutrophilic leukocytes, called Rete bodies, an increase in the thickness of the keratinocyte layer with their histological immaturity, an increase in the level of T-lymphocytes (defenders) and macrophages, as well as other phenomena characteristic of psoriasis.

Skin biopsy is performed together with histological examinations. In this case, the same piece of skin affected by psoriasis is examined. The following indicators indicate a positive result:

• the absence of the granular layer of the epidermis, which protects the skin from dehydration,
• thickening of the germinal layer of the epidermis due to the lengthening and swelling of the epidermal processes, while above the dermal papillae themselves this layer is significantly thinner than normal,
• a large number of blood vessels (capillaries) at the site of the lesion,
• accumulation of neutrophilic leukocytes (granulocytes) in the stratum corneum (Munro microabscesses),
• predominantly lymphohistiocytic infiltration around the vessels.

The main method for diagnosing psoriasis is considered to be taking a scraping from the affected area using a glass slide and analyzing the observed signs (phenomena) of psoriasis, called the psoriatic triad.

The signs of the psoriatic triad appear in a certain order. The first to make itself known is the phenomenon of the stearin spot. It received this name due to the similarity of its manifestations to ground stearin. If you remove the top layer of the papule, noticeable peeling (scales similar in appearance to stearin) is found underneath.

The terminal film phenomenon is the final indicator of the existing pathology. It can be seen in the place of the removed scales, under which a smooth, polished pink surface is found.

If you continue scraping, microscopic hemorrhages in the form of tiny droplets of blood on the surface of the affected area appear under the film. This phenomenon is called the phenomenon of pinpoint bleeding (or the symptom of blood dew).

Psoriasis is also characterized by another specific symptom, known as the Koebner phenomenon, which is observed during the acute phase of the disease. It consists of the formation of new lesions in areas that have been irritated or where the skin has been damaged. Its appearance in some cases helps to clarify the diagnosis.

Some information about the problem can be provided by examining the affected area of skin in UV rays with a wavelength of 308 nm, generated by an excimer laser. In psoriasis, flaky rashes begin to glow.

If psoriatic rashes are localized in the joint area and are accompanied by pain in them, there are all prerequisites for diagnosing psoriatic arthritis. In addition to a blood test, an X-ray of the joints affected by the disease will help to clarify the diagnosis.

One of the new non-traditional methods of instrumental diagnostics of psoriasis is hemoscanning, which is a visual study of fresh blood using a special electron microscope with a high degree of magnification. But it is inappropriate to use it as the main method of research, since there is a high probability of making an incorrect diagnosis.

Biomicroscopy in the diagnosis of psoriasis

When diagnosing psoriasis, eczema and other dermatitis, one of the most effective research methods is contact biomicroscopy, known since the times of the Soviet Union.

The use of contact microscopes for diagnostic purposes, brought close to the object being examined, allows us to observe physiological, pathological and transport processes occurring in living human organs, to measure and record various indicators and even to take microphotographs of the skin.

The basis of contact instrumental examination of the skin was colposcopy, which became widespread in gynecological examinations. The use of a stereomicroscope for examining external skin gave impetus to the emergence of various methods of contact biomicroscopy used in dermatology for the diagnosis of skin diseases, including psoriasis.

The most valuable in this regard is contact fluorescent biomicroscopy, which is one of the variants of laser fluorescent spectrometry. In this case, the study of the "behavior" of tissues under a microscope is combined with their fluorescent analysis, which allows detecting pathology at an early stage of development.

Diagnostics can be performed both with and without additional skin staining with fluorochromes. To study the structure of the stratum corneum, tinting is usually not required; the skin's own fluorescence is sufficient. But to study individual scales of psoriatic plaques in more detail, to identify or exclude the phenomena of Munro's pseudoabscesses and parakeratosis, characteristic of psoriasis, the skin must be tinted with acridine orange (optimal concentration 1: 5000).

The method of contact luminescent biomicroscopy itself is based on the fact that increased cellular respiration causes a change in the natural fluorescence of the skin towards the yellow-green spectrum. At the same time, the blue glow noticeably fades. When diagnosing psoriasis, this is manifested in the detection of cells of the stratum corneum, distinguished by a bright emerald-colored nucleus and pale green cytoplasm, which indicates the phenomenon of parakeratosis. The severity of parakeratosis, which indicates the degree of disruption of cell maturation, can be used to judge the activity of the psoriatic process itself.

Some leukocytes in the stratum corneum may have an unusual color. They are characterized by a green glow of the nucleus and a red color of the cytoplasm. Usually, such cells are collected in groups, forming pseudo-abscesses of Munro, which again allows us to judge the development of psoriasis.

Contact biomicroscopy finds its application not only in the diagnosis of the pathology itself, but also for monitoring the dynamics of the process during therapeutic measures and correction of treatment prescriptions (for example, to determine the time of discontinuation of drugs used for psoriasis).

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Acupuncture points in the diagnosis of psoriasis

According to the theory of acupuncture, the cause of any disease lies in the disruption of the energy balance between the main meridians, of which there are 12 in the human body: the meridians of the lungs, large intestine, small intestine, stomach, liver, gall bladder, spleen, heart, pericardium, urinary bladder, kidneys and the meridian of the three body cavities. Plus, some information can be obtained from the additional 8 meridians. Within these meridians there are certain acupuncture points, which are used to diagnose and treat various diseases, including psoriasis.

When a person gets sick, there is an imbalance of energy in different meridians. Thus, psoriasis is considered a disease with reduced energy in the lung meridian area.

A decrease in the energy potential of one of the meridians entails its increase in others. According to various methods of alternative medicine, a meridian with a large deficiency or excess of energy can be detected in various ways, of which there are more than a hundred. These methods include acupuncture diagnostics by tongue, ears, iris, chakras, spine, pulse, etc.

With the development of radio electronics in the 50s of the 20th century, it became much easier to detect a "sick" meridian, because energy can now be measured using special devices. Indicative in this regard were electropuncture diagnostics according to Voll and the Ryodoraku method.

Both diagnostic methods consider the human body as a certain element of an electrical network with its own energy potential (biopotential, having a current strength of about 3-6 microamps), which can change in different meridians in accordance with the pathology.

According to the Ryodoraku method, a complete picture of the patient's health can be made only by measuring the current strength at the points where various meridians exit the skin. This data is entered into a special Ryodoraku card, according to which the doctor can make a diagnosis even before the first signs of the disease appear.

Voll's method is also one of the safest and most effective methods of preventive diagnostics, which does not require special efforts and bulky equipment. The device for measuring the skin biopotential is based on the fact that the resistance force of the internal electromotive force of various acupuncture points when exposed to an electric voltage of 1.3-1.5 volts at a current of 15 to 20 μA causes the device's arrow to stop in a certain position. It is this indicator that determines the state of the energy potential in a specific biologically active point.

To measure the potential, it is enough for the patient to hold one electrode in his hand, while the other doctor applies it to the acupuncture point. Normally, the biopotential is 50-60 units on the Voll apparatus scale.

Currently, numerous developments are being made of devices for diagnosing psoriasis and some other pathologies, which will allow not only to identify the disease, but also to determine the stage of its development by measuring individual indicators of the amplitude and phase of the biopotential in the area of the acupuncture points of the corresponding meridian.

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Differential diagnostics

Despite the fact that psoriasis diagnostics often does not cause difficulties and it is quite easy to diagnose by specific external signs, there is a certain probability of error, especially if the symptoms are not clearly expressed or there are symptoms indicating damage to internal organs. Here differential diagnostics comes to the fore, which is based on information obtained during examination of the patient, study of the anamnesis, laboratory and instrumental studies.

The purpose of differential diagnosis of psoriasis is to distinguish this pathology from others with similar symptoms or to refute a previously established preliminary diagnosis.

It is important to understand that psoriasis is a multifaceted disease. Its various forms and types can manifest themselves in different ways. This state of affairs only expands the spectrum of pathologies that need to be differentiated.

For example, seborrheic psoriasis initially resembles seborrhea in many ways, caused by disorders in the sebaceous glands. In this case, flaking and itching are observed, as with psoriasis.

Psoriasis differs from seborrhea in that psoriatic rash is localized not over the entire head, but along the edge of hair growth, extending beyond it. In this case, there is no hair loss, and the skin in the affected areas remains dry.

In seborrheic dermatitis localized on the scalp, the rash does not extend beyond the hair growth. On the body, such lesions are located in areas rich in sebaceous glands. The rash has clear boundaries without the pink edging characteristic of psoriasis. They are thinner, with yellow pale scales, painful, but not bleeding when scraped.

The rashes in seborrheic psoriasis can spread further to the skin of the face and neck, resembling psoriasiform neurodermatitis. But again, with psoriasis there is no hair loss and a pronounced change in the shade of the eyelids, and the finely scaly rash when scraped does not have the phenomena characteristic of psoriasis.

Pustular psoriasis can be easily confused with syphilis of the same name upon superficial examination. The difference between these pathologies is that with pustular syphilis, the peeling of papules is noticeable only at the edges, and not along the entire perimeter. Plus, there is a noticeable increase in lymph nodes.

It is not difficult to distinguish psoriasis from allergic or microbial eczema. Despite the fact that both pathologies are characterized by severe itching in the affected areas, the characteristics of the rash are still different. Psoriasis manifests itself in the form of scaly plaques, while the rash with eczema looks like bubbles. Even if the burst and dried bubbles resemble psoriatic scales, when they are removed, a moist surface is formed without pinpoint hemorrhages.

Another poorly studied disease called parapsoriasis has a great similarity with psoriasis. The diseases differ in their nature, although they have similar manifestations, especially in the case of drop-shaped forms of pathologies.

The rashes in parapsoriasis have some similarities with psoriatic rash. The same silvery scales are present on the surface of the papules, but when they are scraped off, the phenomena of the psoriatic triad are not observed. And the papules themselves have different sizes.

Unlike psoriasis, parapsoriasis very rarely chooses the scalp as its localization site, as well as the areas of the elbow and knee joints.

Psoriasis is one of the varieties of lichen, which explains its second name "scaly lichen". The need to distinguish psoriasis from other types of lichen arises due to the fact that many varieties of lichen are contagious and pose a danger to others.

The most similar to psoriasis are red and pink lichen, but if the first is not dangerous to others, the second can be transmitted through direct contact with a sick person.

When diagnosing psoriasis, doctors may encounter a great similarity in the external manifestations of red and scaly lichen. In both cases, there are scaly itchy rashes with shiny smooth skin when scraped off. But if with psoriasis the skin and growth zone are pink or reddish, then for red lichen the affected area is typically colored in a rich crimson-red or even purple hue. A blood test provides more information for differential diagnosis of psoriasis. With red lichen, the number and activity of T-lymphocytes are reduced.

Unlike psoriasis, pink lichen develops rapidly and actively with the appearance of new rashes covering an ever larger area. The onset of the disease is most often accompanied by fever and enlarged lymph nodes.

Manifestations of psoriasis on the nails are in many ways similar to fungal infections (rhumbomycosis, candidiasis, etc.). There is a change in the appearance and thickness of the nail plate, destruction of the nail. Microbiological studies help to make an accurate diagnosis. However, there are a number of signs by which it is possible to determine what the doctor is dealing with: psoriasis or nail fungus.

Psoriasis is characterized by the appearance of a pink or reddish border around the affected nail, which is not observed with nail fungus. However, with a fungal infection of the nail, purulent discharge with an unpleasant odor collects under the nail plate, which is not typical for psoriasis.

In addition, fungal infections tend to spread to other fingers and toes, while psoriasis usually affects individual nails.

But in most cases, a fungal infection is added to psoriasis, especially with reduced immunity, which will be shown by a microbiological study. This means that an accurate diagnosis made during differential diagnostics will help find effective methods for treating nail damage by combating nail fungus and achieving stable remission in psoriasis.

X-ray examinations and complete blood count will be useful in the differential diagnosis of atropaic psoriasis. It is not difficult for an experienced physician to distinguish psoriatic arthritis from rheumatic arthritis. The former is indicated by characteristic rashes and extensive joint lesions. The latter is supported by lesions of the proximal interphalangeal joints, while psoriatic arthritis affects the terminal (or distal) joints.

But the symptoms are not always obvious, which complicates the diagnosis of psoriasis. The rheumatic factor in psoriasis can be tracked by a blood test, and X-rays will help assess the volume and localization of lesions.

As we can see, it is very difficult to overestimate the role of differential diagnostics in this case. After all, the effectiveness of treatment and the future life of a patient suffering from an incurable or treatable disease depend on a correct diagnosis.

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Diagnosis of psoriasis in children

As is known, psoriasis affects both women and men equally, without any specific age restrictions. It affects both adults and children, including infants. The symptoms of psoriasis in children are similar to the manifestations of the disease in adult patients. But as for the varieties and forms, we can say with confidence: the pustular form of psoriasis, as well as psoriatic arthritis and erythroderma in children are observed only in isolated cases.

The most common forms of pathology in children of different ages are plaque and guttate psoriasis. According to research, 8% of infants have specific flaky plaque-like rashes. The cause in most cases is heredity (if the mother or father is sick, the probability of developing the disease is 25%, if both parents - reaches 70%) in combination with environmental and emotional factors.

In infants, scaly lichen, which is also called diaper psoriasis, can easily be confused with ordinary skin irritation when in contact with an unfavorable environment or the same dermatitis. Psoriatic rashes have the same localization in the area of the baby's buttocks and thighs. Most often, in infants, you can see the guttate form of psoriasis, which subsequently spreads to other parts of the body.

In childhood and adolescence, cases of plaque psoriasis are common, which begins its development with the appearance of flaky crusts with a pink border on the knees and elbows of the little patient. Psoriasis can also affect the child's scalp, as well as nails and feet.

Diagnosis of psoriasis in children is often carried out immediately during the examination of the child. Doctors say that this is not difficult to do, because severe forms of pathology with controversial symptoms are not typical for children. Usually, the picture is clarified by an external examination with a study of complaints from the words of parents and the little patient.

Everything is important for a correct diagnosis: hereditary predisposition, which is revealed by questioning the parents, the time of the rash appearance and its behavior, the seasonality of the rash, the presence of itching in the affected area, etc.

Sometimes doctors resort to the help of a dermatoscope, which allows, under high magnification, to examine individual fragments of the scaly rash on the screen.

It is very important to differentiate psoriasis in a child from other pathologies with similar symptoms. Such pathologies, typical for childhood, include:

• ichthyosis of the skin with changes in the stratum corneum,
• xerosis in the form of dry, flaky and itchy skin,
• keratosis of the skin with disturbances of its keratinization,
• types of lichen (red, pink, ringworm),
• various types of dermatitis
• fungal infection on nails,
• allergic or microbial eczema,
• lupus erythematosus in the form of an autoimmune inflammation of the skin,
• fungal skin lesions,
• enteropathic acrodermatitis due to zinc deficiency in early childhood,
• impetigo due to staphylococcal infection, which after the formation of scabs resembles psoriasis,
• and even common skin irritation in infants.

For this purpose, a scraping is performed, and in some cases a biopsy of a piece of skin affected by the disease. Examination of the taken area of skin under a microscope and histological examinations allow us to exclude tumor processes inside the skin and other pathologies dangerous for the baby. When scraping, a mandatory condition for diagnosing "psoriasis" is the presence of the psoriatic triad, which was described above.

The need to diagnose psoriasis in children and treat it in a timely manner is due to the fact that the disease tends to progress from mild to more severe forms (for example, psoriatic arthritis) with damage to internal organs. In addition, psoriasis increases the risk of developing metabolic diseases of an autoimmune nature, which can lead to persistent high blood pressure, diabetes, etc. Not to mention the emotional discomfort associated with the disease, leading to low self-esteem, isolation from society and frequent depression.

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