Eczema

Eczema is an allergic disease accompanied by an inflammatory-dystrophic reaction of the skin, developing against the background of changes in the body's reactivity, prone to a chronic recurrent course, characterized by polymorphism of elements, among which blisters predominate.

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Causes and pathogenesis of eczema

The cause of eczema development has not been sufficiently studied. Both exogenous (chemical substances, medicinal, food and bacterial antigens) and endogenous (antigens-determinants of microorganisms from foci of chronic infection, intermediate metabolic products) factors play an important role in the development of the disease. In the pathogenesis of the disease, the leading role is played by immune inflammation of the skin, developing against the background of the appearance of cellular and humoral immunity, non-specific resistance of hereditary genesis. The hereditary nature of the disease is proven by the frequent detection of histocompatibility antigens HLA-B22 and HLA-Cwl.

Diseases of the nervous, endocrine systems, gastrointestinal tract, etc. also play a major role in its occurrence.

According to modern concepts, development is associated with genetic predisposition, which is confirmed by a positive association of antigens of the histocompatibility system.

A characteristic feature of the disease is the disturbances in the immune and central nervous system in patients. The basis of immune disturbances is the increase in the production of prostaglandins. The latter, on the one hand, activate the production of histamine and serotonin, on the other hand, suppress the reactions of cellular immunity, primarily the activity of T-suppressors. This contributes to the development of an inflammatory allergic reaction, accompanied by an increase in the permeability of the vessels of the dermis and intercellular edema, spongiosis in the epidermis.

Changes in the activity of the nervous system lead to a deepening of immune disorders, as well as to a change in the trophism of the skin. Patients experience increased sensitivity of the skin to the action of various exo- and endogenous factors, which is realized according to the type of viscerocutaneous, cutaneous-cutaneous pathological reflexes.

Reduced immunity combined with trophic disorders leads to a decrease in the protective function of the skin to various antigens and microorganisms. Tone sensitization developing at the onset of the disease is replaced by polyvalent sensitization, characteristic of eczema, as it progresses.

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Symptoms of Eczema

In the course of true eczema, it is customary to distinguish three phases: acute, subacute, and chronic.

Acute eczematous process is characterized by evolutionary polymorphism of rashes, when different morphological elements are found simultaneously. On an erythematous, slightly edematous background, rashes of tiny nodular elements and vesicles, point erosions - eczematous wells, like dew, serous exudate (weeping), small bran-like peeling, small crusts, and fading hyperemia are observed.

The acute stage of the disease is characterized by the appearance of erythema, edema of various sizes and shapes with clear boundaries on the skin. The primary morphological element is microvesicles, which tend to group but not merge. The blisters quickly open with the formation of point erosions separating a transparent opalescent fluid (Devergie's "serous wells"), which dries up with the formation of serous crusts. Subsequently, the number of newly formed blisters decreases. After the process has resolved, fine-lamellar peeling remains for some time. Sometimes, due to the addition of a secondary infection, the contents of the blisters become purulent, pustules and purulent crusts are formed. A characteristic feature is the true polymorphism of the elements: microvesicles, microerosions, microcrusts.

In the subacute form of the disease, the change of stages can occur in the same way as in the acute form, but the process occurs with less pronounced oozing, hyperemia and subjective sensations.

The chronic form is characterized by the presence of increasing infiltrate and lichenification in the affected areas. The process progresses in a wave-like manner, with remissions being followed by relapses. The intensity of itching varies, but itching is present almost constantly. Weeping is observed during exacerbation of the chronic form of the disease. Despite the long course, after recovery the skin acquires a normal appearance. Chronic eczema, like acute eczema, occurs on any areas of the skin, but is more often localized on the face and upper limbs. The disease occurs at any age, somewhat more often in women.

The true eczematous process occurs at any age and is characterized by a chronic course with frequent exacerbations. The rash is located on symmetrical areas of the skin, affecting the face, upper and lower extremities.

One of the most common forms is chronic lichenified eczema, which is characterized by infiltration and lichenification of the skin. Frequent localization on the neck and limbs resembles limited neurodermatitis.

The dyshidrotic eczematous process is localized on the palms and soles and is represented by sago-like dense vesicles, erosive areas and fragments of vesicle covers along the periphery of the lesion. It is often complicated by secondary pyogenic infection (impetiginization), which in turn can lead to the development of lymphangitis and lymphadenitis.

The coin-shaped type of the disease, along with infiltration and lichenification, is characterized by a sharp limitation of the lesions. The process is localized mainly on the upper limbs and is represented by round-shaped lesions. Pustulization is relatively rare. Exacerbations are observed more often in the cold season.

The pruriginous form resembles prurigo in its clinical manifestations, but is distinguished by a later onset and a tendency to exoserose in isolated areas. Dermographism in most patients is red.

Varicose type is one of the manifestations of the varicose symptom complex, localized in most cases on the shins and is very similar to paratraumatic eczema. The clinical features include significant sclerosis of the skin around the varicose veins.

A rarer type of the chronic form of the disease is winter eczema. Although it is believed that the onset of the disease is associated with a decrease in the level of surface lipids of the skin, the pathogenesis remains unclear. Most patients have a decrease in the content of amino acids in the skin; in patients with a severe course of the disease, a decrease in lipid levels leads to a loss of the liquid part of the skin by 75% or more, and thus to a decrease in elasticity and dryness of the skin. Dry climate, cold, hormonal disorders contribute to the occurrence of this pathology.

The winter type of eczematous process often accompanies such diseases as myxedema, enteropathic acrodermatitis and occurs when taking cimetidine, irrational use of local corticosteroids. The disease is most common at the age of 50-60 years.

Patients suffering from the winter type of pathology have dry skin and slightly flaky skin. The skin-pathological process is often located on the extensor surface of the extremities. The fingertips are dry, have small cracks and resemble parchment paper. On the legs, the pathological process is deeper, the cracks often bleed. The border of the lesion is uneven, erythematous and slightly raised. Later, patients are subjectively bothered by itching or pain due to cracks.

The course is unpredictable. Remission may occur in a few months, with the beginning of summer. Relapses mainly occur in winter. Sometimes, regardless of the season, the process lasts for a long time. In severe cases, itching, scratching and irritation upon contact lead to the appearance of a diffuse vesicular-squamous rash and the development of true or nummular forms of eczema. However, the relationship between the winter form of the pathology and these two varieties remains unclear.

In the cracked form of the disease, the indistinctly limited red background of the skin is covered with translucent thin and at the same time wide whitish-gray scales of polygonal outlines. This unique picture gives the impression of cracked skin. It is localized almost exclusively on the shins. Subjectively, itching, burning, and a feeling of tightening of the skin are noted.

The horny type is localized on the palms and less often on the soles. The clinical picture is dominated by hyperkeratosis with deep painful cracks. The boundaries of the lesions are unclear. The pain is more disturbing than the itching. Weeping is extremely rare (during an exacerbation).

The contact form of the pathology (eczematous dermatitis, professional eczema) occurs under the influence of an exogenous allergen in a sensitized organism and is usually limited and localized. It is most often located on the back of the hands, the skin of the face, neck, and in men - on the genitals. Polymorphism is less pronounced. It is quickly cured by eliminating contact with the sensitizing agent. Very often, the contact type is caused by professional allergens.

Microbial (posttraumatic, paratraumatic, varicose, mycotic) eczematous process is characterized by asymmetrical location of foci, mainly on the skin of the lower and upper extremities. A characteristic sign is the presence of pustular rashes, purulent and hemorrhagic crusts on an infiltrated background, along with areas of weeping.

The lesions are bordered by a border of exfoliated epidermis; pustular elements and impetiginous crusts can be seen along their periphery. The plaque (coin-shaped) form is characterized by a symmetrical generalized nature of the lesion in the form of slightly infiltrated spots with slight weeping and sharp boundaries.

Seborrheic eczema is characterized by the onset of the process on the scalp with subsequent transition to the neck, auricles, chest, back and upper limbs. The disease usually occurs against the background of oily or dry seborrhea, in both cases - on the scalp. Then, weeping may occur with subsequent accumulation of a large number of crusts on the surface of the skin. The skin behind the auricles is hyperemic, edematous, covered with cracks. Patients complain of itching, soreness, burning. Temporary hair loss is possible.

The lesions can also be localized on the skin of the trunk, face, and limbs. Point follicular nodules of a yellowish-pink color appear, covered with greasy grayish-yellow scales. Merging, they form plaques with scalloped outlines. Many dermatologists call this disease "seborrhea."

A microbial eczematous process is clinically similar to seborrheic; it also has lesions with sharp boundaries, often covered with dense, greenish-yellow, and sometimes bloody crusts and scales; under them, a greater or lesser amount of pus is usually found. After removing the crusts, the surface is glossy, bluish-red, weeping and bleeding in places. This type of disease is characterized by a tendency for lesions to grow peripherally and the presence of a crown of peeling epidermis along the periphery. Around them, so-called seedings (small follicular pustules or phlyctenae) are found. Itching intensifies during an exacerbation of the disease. The disease is most often localized on the shins, mammary glands in women, sometimes on the hands. It occurs in most cases at the site of a chronic pyococcal process and is distinguished by asymmetry.

Microbial eczema should be distinguished from impetiginous eczema, which occurs when the eczematous process is complicated by a secondary pyogenic infection.

Yeast eczema is a chronic form of candidiasis (candidomycosis, monidiasis) caused by Candida albicans, tropicalis, crusei. Increased humidity and repeated macerations of the skin of a mechanical and chemical nature, weakening of the body's immunobiological resistance, disruption of carbohydrate metabolism, vitamin deficiencies, gastrointestinal diseases, prolonged contact with products containing yeast and other factors contribute to the formation of yeast lesions of the skin.

Candidiasis of the skin with subsequent yeast eczematous process is observed mainly in natural folds (in the groin area, around the anus, genitals), around the mouth, on the fingers. Flat, flaccid vesicles and pustules appear on the hyperemic skin, which quickly burst and erode. Erosions are dark red with shiny liquid, edema, polycyclic outlines, sharp borders and an undermined crown of macerated epidermis. Large areas with garland-like outlines are formed by merging erosions. There are new rashes around. In some patients, the elements look like solid, slightly moist erythematous foci. Candidiasis can separately affect the interdigital folds of the hands (usually the third interval), the head of the penis and the skin of the preputial sac, palms and soles, field ridges and nails, lips, etc.

In its clinical course, the mycotic type of pathology is similar to dyshidrotic and microbial. It occurs in people who have suffered from mycosis of the feet for a long time. The appearance of multiple blisters is typical, mainly on the lateral surfaces of the toes, palms and soles. The blisters can merge and form multi-chamber cavities and large blisters. After the blisters open, wet surfaces appear, which, when dry, form crusts. The disease is accompanied by swelling of the extremities, itching of varying degrees of severity, and pyogenic infection often joins.

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Classification of eczema

There is no single, generally accepted, unified classification of eczema. A rational division is into true, contact, and microbial (mycotic) forms.

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Differential diagnosis

Eczema must be differentiated from diffuse neurodermatitis, dyshidrosis, and allergic dermatitis.

Dyshidrosis usually occurs in spring and summer against the background of vegetative-vascular dystonia and is characterized by the localization of blisters on the palms. The blisters are the size of a pinhead and have a dense cover, transparent contents. After a few days, the blisters either dry up or open up with the formation of erosions, and then regress.

Allergic dermatitis occurs with repeated contact with various household and professional chemical agents (cosmetics, medicines, washing powders, varnishes, paints, chromium, cobalt, nickel salts, plants, etc.) due to sensitization to them.

The clinical picture of the process resembles acute eczema, but against the background of hyperemia and edema, larger bubbles appear instead of microvesicles. The course is more favorable, the manifestations disappear after eliminating contact with the allergen.

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Treatment of eczema

General treatment consists of prescribing sedatives (bromine, valerian, camphor, novocaine, etc.), low-dose antidepressants (depress, ludiomil, etc.), desensitizing drugs (calcium chloride or calcium gluconate, sodium thiosulfate, etc.), antihistamines (tavegil, loratal, analergin, fenistil, etc.), vitamins (B1, PP, rutin, etc.), diuretics (hypothiazide, uregit, fonurit, furosemide, etc.). If therapy is ineffective, corticosteroids are prescribed orally. The dose depends on the severity of the disease, usually 20-40 mg per day.

Local treatment depends on the period of the disease. In case of oozing, lotions are prescribed (resorcinol 1%, zinc 0.25-0.5%, Sol. Argenti nitrici 0.25%, furacilin, rivanol), in case of subacute form - pastes (naphthalan, ichthyol 2-5%) and in case of chronic eczema - boric-tar paste, ointment with ASD 5-10% (B fraction), hormonal ointments, etc.

Of the antipruritic agents, Fenistil gel has a good effect when applied externally 3 times a day.

Literature data show that elidel has a high therapeutic effect, reducing the duration of treatment. The effectiveness of therapy is enhanced by combining elidel with local glucocorticosteroids.

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Basic principles of treatment

• It is necessary to prescribe a diet with reduced consumption of table salt, carbohydrates, with the exclusion of nitrogenous extracts, food allergens, including citrus fruits, with the inclusion of vegetables, fruits, fermented milk products, and cottage cheese in the diet.
• For the purpose of hyposensitization, it is recommended to take calcium salts, sodium thiosulfate, antihistamines (diphenhydramine, diprazine, suprastin, tavegil, etc.).
• Use of sedatives (bromides, tinctures of valerian, motherwort, tazepam, seduxen, etc.).
• The use of vitamins A, C, PP, and group B as stimulants.
• The choice of dosage form for external use depends on the severity of the inflammatory reaction, the depth of infiltration and other manifestations of the disease. In the acute stage, in the presence of microvesicles, erosions, exudation, lotions and wet-drying dressings with 1-2% tannin solution, 1% resorcinol solution are indicated, in the subacute stage - oil suspensions with norsulfazole or dermatol, paste (5% boric-naphthalan, 1-5% tar, 5% ASD 3-I fraction), in the chronic stage - ointments (tar, dermatol, boric-naphthalan, etc.).
• Physiotherapeutic methods: ultrasound, hydrotherapy, suberythemal doses of ultraviolet rays (at the convalescence stage), etc.

Prevention of recurrence of eczema

• In-depth examination of patients to identify concomitant pathology, prescription of corrective therapy
• Rational employment: career guidance for sick adolescents.
• Following a diet.
• Medical examination of patients.

The frequency of observation by a dermatologist is 4-6 times a year, by a therapist and neurologist - 1-2 times a year, by a dentist - 2 times a year.

Scope of examination: clinical blood and urine tests; stool analysis for helminth eggs (2 times a year); biochemical studies (blood for sugar, protein fractions, etc.); allergological studies characterizing the state of cellular and humoral immunity.

• Sanatorium and resort treatment.

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