Anetoderma is a focal atrophy of the skin with an unclear etiology, in which there is a predominant lesion of the elastic fibers of the dermis. Symptoms of this disease are the appearance of foci of various shapes and sizes on the skin of the trunk and extremities, the level of which is below or above the surface of the unchanged skin (depending on the form of the disease). Diagnosis is based on dermatological examination data, in controversial cases, a skin biopsy is performed in the lesions with further histological examination. Due to the uncertainty of the etiology of the disease, specific treatment has not been developed, some antibiotics, vitamin preparations, and means that improve tissue regeneration are used.
Anetoderma, or spotted skin atrophy, is presumably a multifactorial disease in which the elastic fibers of the dermis are affected with their degradation and the development of concomitant disorders (thinning of the epidermis, vascular anomalies). Mainly affects women aged 20 to 40 years living in the central part of Europe, and people from this region living in other countries, spotty skin atrophy occurs very rarely. This refutes genetic theories that explain the development of anetoderma by mutations of some genes. Anetoderma occurs as an independent disease, and as part of the symptom complex of Blegvad-Haxthausen disease – a genetic pathology in which cataract and osteoporosis are also observed.
Most researchers tend to believe that a combination of nervous, endocrine, metabolic and immunological disorders plays an important role in the development of anetoderma. Also, the participation of microorganisms such as spirochetes in the development of spotted skin atrophy has been practically proven. Indirect evidence of this is the residence of most of the patients in central Europe (almost coincides with the distribution area of Br. burdorferi) and a positive reaction to the treatment of anetoderma with penicillin antibiotics. In addition, a case of the birth of a baby with spotted atrophy, whose mother suffered from intrauterine borreliosis, is described.
The pathogenesis of anetoderma is characterized by a certain stage. Initially, nonspecific inflammatory phenomena occur in the dermis – lymphocytic-macrophage infiltration with the participation of neutrophils and plasma cells. As a rule, this stage is almost asymptomatic, therefore, patients with spotted skin atrophy at this stage are rarely detected in outpatient dermatology. Then the infiltration is somewhat resolved, but still a small number of immune system cells remain in the tissues. It is assumed that macrophages and neutrophils begin to produce elastase, which destroys the elastin fibers of the dermis, triggering the development of anetoderma.
Other theories indicate that the reason for the development of disorders of this type may be a decrease in elastin synthesis, a shift in the balance in the elastase-antielastase system, or problems with the release of the amino acid desmosin.
The final result of the above processes in anetoderma is the almost complete disappearance of elastic fibers in the dermis, partial degradation of collagen, thinning of the epidermis. The process does not extend to the entire skin, but has a focal character, the reasons for this are also unknown today. Given that there are several clinical forms of anetoderma, it is assumed that the pathogenesis of this condition can proceed in different ways. However, the result of each is the same – almost irreversible focal dystrophy of the skin.
To date, there are primary and secondary forms of the disease – the etiology of the first is just a scientific problem, while the second occurs in place of tuberculous, syphilitic and other inflammatory skin lesions. Most researchers believe that it is impossible to compare the primary and secondary forms of this pathology, because, despite the external similarity, completely different processes and factors probably play a role in their development.
In addition to the division of anetoderma into primary and secondary, there is also a classification of this condition according to clinical forms characterized by different symptoms and manifestations. The reasons for such differences are currently insufficiently studied, presumably the development of a particular symptom complex is caused by many factors at once. These include the possible etiology of anetoderma, reactivity of the body, activity of the immune system, neuroendocrine disorders. Dermatologists distinguish three clinical types of this pathology:
- The classical form (Yadasson type);
- Schwenninger-Buzzi anetoderma;
- Anetoderma of the Pellizari type.
It is the most common form of anetoderma, so its clinical course is considered the most studied. Initially, spots with a diameter of 5-10 millimeters appear on the surface of the skin of the trunk, limbs, neck and face, having a pinkish color. A characteristic diagnostic sign of Jadassohn-type anetoderma is the absence of spots on the palms and soles.
For 7-12 days, there is an increase in the diameter of the hearth, which eventually reaches 2-3 centimeters. No subjective sensations (soreness, itching) occur during the development of this type of anetoderma. Then the stage of atrophy abruptly begins – the skin on the surface of the foci becomes thinner, easily crumpled, its surface becomes pale, the level of lesions is slightly higher than normal skin, which gives them the appearance of hernia-like protrusion. Atrophic changes in anetoderma begin in the center of the focus, gradually spreading to the periphery.
Schwenninger-Buzzi type anetoderma
It differs from the previous version by the almost complete absence of the inflammatory stage of the disease. On the unchanged skin of the back and upper extremities, foci with a diameter of 2-3 centimeters suddenly appear, sharply protruding above the surrounding tissues. At first, these protrusions are dense, but atrophy develops quickly enough, the skin on the anetoderma-affected areas are covered with wrinkles, telangiectasia often occurs on them. Also, in the foci of Schwenninger-Buzzi type anetoderma, small nodules are often found, which are extensions of the capillaries of the dermis.
Anetoderma of the Pellizari type
Anetoderma of the urticular-edematous type is characterized by the initial development of skin rashes in the form of blisters, similar in appearance to urticaria. The difference between this variant of skin atrophy and true urticaria is the complete absence of subjective disorders, including itching. After a few days, atrophic changes characteristic of anetoderma begin to develop on the site of edematous elements.
The course of the disease is chronic and sometimes recurrent. Resolution of atrophic foci with anetoderma of any type does not occur, they remain for life, therapeutic methods can slow down atrophic processes at an early stage.
Diagnosis of anetoderma is most often performed on the basis of a dermatological examination, sometimes a skin biopsy is performed in the lesions for histological analysis. The results of the skin examination depend on the clinical type of the disease and the stage of its development. Common to all variants of anetoderma are such manifestations as thinning and slight creasing of the skin in the foci, its pallor, herniated protrusion (in rare cases, the opposite is observed, the sinking of the skin). Palpation reveals one of the most characteristic symptoms of anetoderma – when pressing on the pathological focus, the finger seems to fall into the void. This is reflected in the name of this pathology (from the Greek anetos – emptiness).
Histological studies performed at the initial stages of anetoderma development often reveal moderate lymphocytic infiltration with predominant perivascular localization. Other manifestations of nonspecific inflammation include the presence of macrophages, neutrophils in the skin, and sometimes plasmocytes are detected. At the atrophic stage of anetoderma, lymphocytic infiltration is much less pronounced, however, a decrease or complete absence of elastic fibers, the presence of inclusions in fibroblasts, and thinning of the epidermis are revealed. With Schwenninger-Buzzi type anetoderma, vascular disorders may be detected in the form of extensions of the dermis capillaries.
Differential diagnosis should be carried out with conditions such as atrophic lichen planus, focal scleroderma, Pasini-Pierini atrophoderma.
Specific therapy for anetoderma has not been developed, since the causes of such processes in the skin have not yet been precisely established. Of the drugs of general action, a decrease in the rate of atrophy is caused by antibiotics (penicillin), some antimalarial drugs, vitamin and mineral complexes. Most likely, their effectiveness in anetoderma is associated with a decrease in the influence of infectious agents (such as Br. burdorferi), as well as a restorative effect on the body. According to some reports, injections of hyaluronidase into the lesions also slow down atrophic processes and reduce the severity of the manifestations of the disease.
Local treatment also includes the introduction of hyaluronidase into anetoderma-affected tissues using electrophoresis. There are indications of the beneficial effect of phonophoresis with tocopherol and dimethyl sulfoxide. Of the other local drugs used in the therapy of anetoderma, tissue regeneration stimulants are especially often used. Sometimes antithrombotic drugs are used to treat Schwenninger-Buzzi type anetoderma. However, any treatment methods are effective only at the initial stages of the development of the disease. In the case of already formed atrophy, it will not be possible to return the skin to its original state.
Prognosis and prevention
Even the most severe course of anetoderma does not threaten the patient’s life, in this regard, the prognosis of the disease is favorable. However, the prospects for recovery are often rather doubtful. Treatment of anetoderma can be effective only at the initial, inflammatory stages of pathology, and on them the symptoms are either very weakly expressed (with the Jadasson type), or completely absent (the Schwenninger-Buzzi type). In addition, a dermatologist does not always recognize this disease in a timely manner, since it is not among the most common. Later treatment to a specialist and difficulties in diagnosis lead to the fact that the treatment of anetoderma begins with already sufficiently pronounced atrophic phenomena, which in most cases are irreversible.