Erythema annulare centrifugum is a skin lesion of various etiologies, manifested by erythematous rashes of various (most often ring-shaped) shapes on the skin of the trunk, lower and upper extremities. Characterized by a long course, it is difficult to treat. Diagnosis is based on the study of anamnesis, examination data and the results of various serological studies conducted to exclude infectious diseases. There is no etiotropic treatment, usually desensitizing therapy is carried out, antibiotics and vitamin preparations are used. In some cases, rashes disappear when the provoking pathology is eliminated.
Erythema annulare centrifugum is a group of skin diseases with similar manifestations – the formation of ring-shaped and shapeless erythematous rashes. One of the forms of this condition was described in 1916 by the French dermatologist J. Daria, at the moment it is called ring-shaped centrifugal erythema Daria. In addition to this type of disease, there are several other types of pathology that differ in age of development, etiology and clinical manifestations. Various types can occur in children, adolescents or the elderly. Most varieties of erythema are equally often diagnosed in men and women, Darye’s erythema is several times more common in males.
The etiology and pathogenesis in many cases remain unclear, there are only assumptions about the influence of certain factors. The rheumatic form of pathology is caused by rheumatic joint damage, but the cause of skin manifestations has not yet been established. Migrating erythema annulare centrifugum, more often detected in children and adolescents, is probably associated with various viral and bacterial infections.
The etiology of Darya causes the greatest number of questions. The development of this form of the disease, presumably, may be due to a fungal infection of the skin, autoimmune processes and the intake of certain medications. In addition, Darya’s erythema often occurs against the background of various helminthiasis, which also testifies in favor of the autoimmune nature of the disease. Many cases of the appearance of erythema annulare centrifugum against the background of tonsillitis, other inflammatory processes, endocrine disorders and hormonal disorders have been described. Oncologists note that sometimes erythema annulare centrifugum is part of the paraneoplastic syndrome. Thus, this condition is a special form of reactive dermatosis of various etiologies.
In addition to the allocation of the above-listed forms of erythema annulare centrifugum (rheumatic, migrating, Daria), in practical dermatology there is a classification made taking into account the peculiarities of the clinical course, which generally differs in the nature of rashes, duration and other characteristics. Currently, there are four clinical forms of erythema annulare centrifugum. The first symptom of all forms is the formation of red spots on the surface of the skin, sometimes with itching. In the subsequent course of each form acquires its own characteristic features.
Flaky erythema annulare centrifugum develops more often with helminthiasis and paraneoplastic syndrome. The area of redness eventually begins to peel off, a slight pigmentation of the skin is detected in the center, the redness becomes less pronounced. The growth of education continues along the periphery, the size of pathological foci reaches 15-20 centimeters. The changes in the central part are weakly expressed, which in combination with peripheral growth leads to the appearance of characteristic formations of a bizarre shape. The duration of the existence of the focus can be several months, after the resolution of the rash, the skin remains pigmented. Often new spots and areas of erythema annulare centrifugum are formed, with a long-term recurrent course of the disease, bizarre patterns of erythema sites and hyperpigmentation zones are revealed on the patient’s body.
Vesicular erythema annulare centrifugum has an unclear etiology, usually occurs against the background of reduced immunity and endocrine disorders. Even at the stage of the red spot, small bubbles filled with serous fluid appear on the edges of the hearth. In the future, as with flaky erythema annulare centrifugum, there is a peripheral growth of the pathological focus with the formation of a hyperpigmentation site in the center. During the growth process, small vesicles are constantly formed and disappear along the edges of the focus. The course of this form of erythema annulare centrifugum is chronic recurrent, rashes may disappear after a few weeks or months, replaced by the development of new foci.
Simple erythema annulare centrifugum occurs when allergic to food or medicines. It is the easiest variant of the disease, characterized by a fairly rapid transformation of spots into ring-shaped structures. Peeling of the skin or the formation of vesicles does not occur, the only manifestation of the disease is redness. Ring-shaped structures resolve without a trace a few days or even hours after formation.
Persistent erythema annulare centrifugum has an unclear etiology, accompanied by the formation of small spots and rings with a diameter of up to 1 centimeter. Sometimes vesicles or peeling areas occur in the affected area. A long course is characteristic.
The literature also describes such forms as telangiectatic, compacted and purpurous. Due to the low prevalence (less than a hundred cases), some dermatologists believe that these forms do not exist, and the described changes are other skin diseases with the formation of ring-shaped structures. The question of the validity of such an opinion remains debatable today.
The diagnosis of “erythema annulare centrifugum” is based on anamnesis data and the results of a dermatological examination. In controversial cases, a skin biopsy is performed in the area of pathological foci. When examined by a dermatologist, erythematous rashes of various shapes and sizes are determined, often in the form of bizarre closed lines and stripes. Depending on the shape of the erythema annulare centrifugum, along with redness of the skin, peeling, formation of papules or vesicles may occur.
When studying the patient’s anamnesis, diseases that provoked the development of this form of reactive dermatosis are often detected. Helminthic invasion, skin mycoses, malignant neoplasms, inflammation of the elements of the oral cavity and upper respiratory tract are possible. In the absence of these diseases, the patient may be assigned laboratory and instrumental studies to assess the condition of various organs and systems and determine the causes of the development of erythema annulare centrifugum. One should pay particular attention to the possibility of oncological damage, since erythema annulare centrifugum is sometimes a manifestation of paraneoplastic syndrome.
Changes in the general blood count in erythema annulare centrifugum have a non-specific character and mainly contribute to the establishment of the nature of the provoking factor. For example, eosinophilia may indicate a helminthic invasion or allergy, leukocytosis – acute or chronic inflammation. Quite often, with erythema annulare centrifugum, dysproteinemia is detected – a violation of the ratio between individual fractions of plasma proteins. Histological examination of the skin usually reveals an unchanged epidermis with edema and pronounced leukocyte infiltration of the dermis. Histoimmunofluorescence analysis confirms the accumulation of class G immunoglobulins in the basement membrane of the epidermis. Differential diagnosis is carried out with seborrheic eczema, granuloma annulare and syphilitic roseola.
Etiotropic treatment of erythema annulare centrifugum is absent, however, successful therapy of the provoking disease can significantly reduce the manifestations of this condition. Depending on the revealed pathology, skin mycoses, tonsillitis and diseases of the gastrointestinal tract are treated. If necessary, the oral cavity is sanitized. In the process of treating the underlying disease, antibiotics, anthelmintic agents and other drugs are used. In the presence of a malignant neoplasm, the therapy plan is determined depending on the localization, prevalence and type of neoplasia.
Along with the treatment of the underlying disease with erythema annulare centrifugum, desensitizing therapy is carried out. Antihistamines (cetirizine, chloropyramine), calcium chloride and sodium thiosulfate are used. To normalize metabolism, patients are prescribed vitamin therapy, especially vitamins C, A and E. Patients are shown a hypoallergenic diet with an increase in the amount of carbohydrates in the diet. In severe cases, corticosteroids (prednisone) are used to reduce inflammatory phenomena. Topical antipruritic ointments are applied, in the presence of vesicles, antiseptic agents are used to prevent secondary infection.
Prognosis and prevention
In general, the forecast is favorable. This condition does not threaten the patient’s life and, when the cause of development is established, in some cases it can be completely cured. With erythema annulare centrifugum of unexplained etiology, the prognosis worsens, since specialists can only carry out symptomatic therapy and treat identified diseases that may not be related to skin lesions in any way. Sometimes, after intensive desensitizing therapy, erythema annulare centrifugum gradually disappears, but after a while it reappears. In such cases, it is recommended to constantly follow a hypoallergenic diet, periodically take vitamins and antihistamines.
Prevention consists in timely treatment of inflammatory diseases of the respiratory tract, regular sanitation of the oral cavity and prevention of worm infestation. Patients with erythema annulare centrifugum should regularly visit a dermatologist, even during remission. In particularly severe cases, a dispensary registration is required.