What Is Nummular Eczema And Its Causes

What Is Nummular Eczema And Its Causes

Eczema is an acute or chronic recurring disease characterized by an inflammatory reaction that forms under the influence of exogenous or endogenous factors, polymorphism of rash elements, and severe itching.

The problem of eczema is currently becoming increasingly relevant. In the structure of the incidence of chronic dermatoses, eczema accounts for up to 40% of all skin diseases. 

The incidence of eczema occurs in all age groups, often associated with occupational diseases. According to the results of epidemiological studies, various types of eczema are one of the most common diseases in the practice of a dermatovenerologist. 

The incidence among people of the working population is up to 10%. The loss of temporary disability reaches 36% of all labor losses with dermatoses. Among hospitalized patients with eczema account for more than 30%.

Among women, the incidence of eczema is more common than in men. In recent years, eczema has a tendency to a more severe course with frequent relapses, a significant spread of the process on the skin, and resistance to treatment.

What is Nummular Eczema?

Nummular eczema is characterized by a single, non-specific morphological element, namely a round or oval eczematous plaque with clear boundaries. 

The disease occurs both in patients with atopy and without it; a combination with contact allergic reactions is rare. 

Local physical or chemical trauma plays a role in some cases, nummular eczema sometimes develops at the site of the injury or scar. An association with dry skin with low humidity is noted. Stress is given some importance, but it is unlikely to be the root cause of the disease. 

Cases of the development of nummular eczema associated with alcohol abuse are described. 

With massive seeding of elements with staphylococci, the severity of clinical manifestations increases, even in the absence of clinical signs of infection. 

A diagnostic sign of nummular eczema is a monotopic plaque formed by closely grouped thin-walled vesicles on an erythematous background. In the acute stage, the elements of stagnant red color, get wet, covered with crusts and are extremely sensitive 

It is very characteristic of this disease that the "sleeping" elements can be activated again, especially after a premature termination of treatment. 

Nummular eczema is a chronic disease with a relapsing course and in complete remission, manifested by regression in the central part of the foci. Deterioration in most forms is observed in the cold months of the year; 

Nummulyarnaya eczema can simulate fungal skin lesions, but even if regression central foci nummulyarnoy eczema remaining region wider, the presence of a larger amount of bubbles, more brightly colored than the roller when trichophytosis, for which a characteristic peeling circumferentially elements 

To avoid mycosis conducted laboratory the study of scraping from the surface of the focus. 

With psoriasis, the rashes are dry, with more pronounced peeling and less irritable. Rashes with annular granuloma do not flake 

What are the causes?

Eczema develops as a result of a complex effect of etiological and pathogenetic factors, including endocrine-metabolic, infectious-allergic, vegetovascular, and hereditary]. Of great importance in the formation of eczema is given to the immunogenetic characteristics of the body - association with the body's HLA-B22HLA-Cw1 hypertension.

A genetic predisposition determines a violation of immune regulation, the function of the nervous and endocrine systems. In eczema, polygenic multifactorial inheritance occurs with pronounced gene expressivity and penetrance. 

With a disease of one of the parents (mainly the mother), the chance of getting eczema in a child is 40%, with a disease of both parents up to 60%. 

An important pathogenetic value is the pathology of the gastrointestinal tract and hepatobiliary system. Failure of the intestinal barrier, which is most characteristic of children, leads to the absorption of unsplit protein in the blood. Allergic reactivity is also of great importance in the development of eczema.

According to modern concepts, the development of eczema is dominated by T-lymphocytes that carry specific antigen receptors on their surface and secrete a number of pro-inflammatory cytokines that cause the development of tissue inflammatory reactions. 

Exogenous effects are extremely diverse. They cause eczematous skin changes according to the delayed-type hypersensitivity mechanism caused by contact with chemical, biological, medicinal products, and antigenic microbial determinants in the foci of chronic infection.

Clinical signs of eczema may include itching, redness, and flaking of the skin, and the presence of grouped papulovesicular. During the eczematous process, the following stages can be distinguished: erythematous, papular, vesicular, stage of weeping, cortical stage, stage of desquamation [1]. Depending on the characteristics of the clinical picture, the following forms of eczema are distinguished.

• true eczema: idiopathic, dyshidrotic, pruriginous, horny (tylotic);
• microbial eczema: nummular, peritraumatic, mycotic, intertriginous, varicose, sycosiform, eczema of the nipples and paranasal circle of the young gland of women;
• eczema seborrheic;
• eczema for children;
• Eczema is a professional.

Types of Nummular Eczema

True eczema

In the acute stage, true eczema is manifested by the appearance of vesicles, erythema, pinpoint erosion with weeping, serous crusts, excoriation, but there may be papules and pustules. The boundaries of the foci are fuzzy. 

The process is symmetrical in nature, more often the face and limbs are affected, with alternating healthy and affected skin. Also, the process can spread to other areas of the skin up to erythroderma. 

After the transition to the chronic stage, hyperemia becomes stagnant, areas of lichenification and cracks appear. Often the process can be complicated by a pyogenic infection, purulent crusts and pustules appear.

Coin-like (Nummular) Eczema

Nummular eczema is predominantly an adult disease. Men are more likely to be affected than women. The peak incidence in both sexes occurs between the ages of 50 and 65 years. The second peak in women is observed at the age of 15 to 25 years. 

In newborns and children, nummular eczema is a rare disease. In children, it begins with five years. The pathogenesis of nummular eczema is still unknown. In most patients, atopy in a personal or family history is not detected, however, with tropical eczema, nummular plaques can be observed. 

As a cause of the disease, many factors are considered. In elderly patients, a decrease in skin hydration is noted. In 68% of patients, foci of infection were detected, including in the area of ​​teeth and the respiratory tract. Also, a role it played in the occurrence of nummular eczema to environmental allergens, such as house dust mites. 

Clinically defined, coin-like plaques from merging papules and papulovesicular are clinically visualized. Characteristic features are shallow weeping and crusting. However, crusts can cover the entire surface of the plaque. 

The size of the plaques is 1 to 3 cm in diameter. The surrounding skin is in most cases normal, but maybe xerotic. The intensity of the itching varies from minimal to severe. There may be a resolution of the elements in the center, which is noted with ring-shaped forms of the disease. 

Microbial eczema

Microbial eczema is a polyetiological disease. The role of the skin barrier in the pathogenesis of microbial eczema is important. Violation of the integrity of the skin when it is resorbed due to itching forms the entrance gate for infection. 

The exudation that accompanies eczema promotes the concentration of proteins on the surface of the skin and creates favorable conditions for the multiplication of a secondary infection. Of great importance is the state of the skin microbiota in patients with microbial eczema. In scrapings of the affected epidermis in patients with microbial eczema, Staphylococcus aureus, Staphylococcus haemolyticus, non-lipophilic yeast fungi, mainly of the genus Candida, are sownspp. 

The leading pathogens of microbial eczema are infectious allergens - bacterial, viral, fungal protozoal, and others. Exogenous stimuli can also provoke the disease - physical, mechanical, and biological. The immune allergic theory is clearly confirmed by empirically identified staged stages of the course of microbial eczema. 

Initially, the disease develops in the form of eczematization in place of non-allergic pyodermatitis, and then through localized forms, it is transformed into a generalized process. Foci of microbial eczema often occur in places of persistent pyoderma and around purulent wounds. Microbial eczema is a complication of dermatophytosis of large folds and feet, superficial candidiasis of the skin. Sensitization may initially be monovalent, but over time it becomes multivalent. Staphylococcus aureus and Staphylococcus haemolyticus. 

Seborrheic eczema

Seborrheic eczema begins on the scalp. The lesions spread to the behind the ear, neck, upper chest, interscapular region, flexion surface of the limbs; like seborrheic dermatitis, seborrheic eczema is localized in areas of the skin with a large number of sebaceous glands and does not have clear boundaries. Within the foci, the skin is hyperemic, edematous, small yellowish-pink papules, fatty yellowish scales, and crusts are visible on its surface.

Varicose eczema

Varicose eczema is associated with the presence of a patient with varicose veins. The lesion is localized on the skin of the lower extremities, mainly in close proximity to varicose ulcers, mainly in the lower third of the leg. In the development of the disease, maceration of the skin, various injuries, as well as irrational treatment of varicose ulcers play. The disease is accompanied by itching. Differentiate with erysipelas, pretibial myxedema.

Sycosiform eczema

Sycosiform eczema develops against the background of vulgar sycosis, the pathological process extends beyond the area of ​​hair growth. As a rule, the skinning process is localized on the chin, pubis, upper lip, axillary region. Clinically, itching and weeping, serous wells, over time, areas of skin lichenification appear.

Children's eczema

Infantile eczema is manifested by clinical signs of true, microbial, and seborrheic eczema. The first manifestations appear at the age of 3-6 months. Exudation processes predominate on the skin. The lesions are symmetrical, brightly hyperemic, edematous, pronounced wetting, layering of crusts. 

Milk crusts appear. Erythematous foci have a shiny surface, hot to the touch. The lesions are localized on the cheeks, forehead, auricles, scalp, extensor surfaces of the extremities, buttocks. The nasolabial triangle remains untouched. Patients are concerned about itching and insomnia. At the age of 2-3 weeks of life, a clinical picture of the disease can develop a characteristic clinical picture of the disease. Often transformed into atopic dermatitis.

Eczema of the nipples of the mammary glands

Eczema of the nipples of the mammary glands is a consequence of an injury to the nipples during feeding the baby, but in some cases, the etiology cannot be determined. It is characterized by slight erythema, mild infiltration, weeping, and the presence of serous-hemorrhagic crusts, the appearance of pustules and cracks is possible. Usually, the pathological process has a two-sided character and is not accompanied by a compression of the nipples.

Occupational eczema

Occupational eczema develops under the influence of industrial allergens. Occupational allergens include metal alloys, mercury compounds, penicillin, and semi-synthetic antibiotics, epoxies, and synthetic adhesives. With occupational eczema, a delayed-type hypersensitivity reaction develops. The clinical picture has all the signs of ordinary eczema. Occupational eczema develops mainly in open areas of the skin, in places of contact with an irritant. With the disappearance of the etiological factor, the disease quickly resolves.

Paratraumatic Eczema

Paratraumatic eczema develops in the area of ​​postoperative scars, in places of improper application of plaster casts, in places of osteosynthesis. Clinically, island-inflammatory erythema occurs, papules or pustules appear, with further formation of crusts. Possible deposition of hemosiderin in the affected tissues.

Diagnosis is based on the history and clinical picture of the disease. Laboratory studies are carried out: a biochemical blood test with the determination of ALT, AST, triglycerides, total protein, creatinine, total bilirubin, glucose; general blood analysis; clinical urine analysis; determination of the level of total IgE in serum using ELISA; skin tests; determination of antibodies to giardia antigens, roundworm, toxocar, and others; histological examination of skin biopsies are performed according to indications for the purpose of differential diagnosis. 

TREATMENT. 

Potent corticosteroid ointments are usually prescribed, including with the addition of antimycotics, antibiotics. 

Tar paste or ointment can be applied with a subacute stage on the dried elements. Emollients and oil bath additives help moisturize the skin and prevent relapse. Antibiotics inside, antihistamines are indicated for severe exudation. 

In severe cases, it may be necessary to prescribe corticosteroid hormones inside.