Acrodermatitis continua is a pustular skin disease of unclear etiology and pathogenesis, characterized by localization of the pathological process in the extremities. The clinic is dominated by a rash of primary elements in the form of pustules, which tend to merge. Initially, as a rule, the thumb of the hand is affected, then other fingers, the back of the hands and feet. The skin is swollen, bluish; the nail bed is thickened, covered with crusts; the nail plate is dirty yellow; movements cause pain. The diagnosis is made on the basis of clinical manifestations confirmed histologically. Treatment is symptomatic, antibacterial, anti-inflammatory.
ICD 10
L40.2 Acrodermatitis continua [Hallopeau]
General information
Acrodermatitis continua – acropustulosis of a recurrent course, which is based on inflammation of the skin. Some dermatologists tend to consider the disease a special kind of pustular psoriasis or dermatitis of During. The basis for this is the common primary element of the skin rash – the pustule. In 1879, Hallopeau, summing up seven years of clinical observations, described limb pustulosis, considering it a “twin” of the herpetiform impetigo of the Gebra. In 1884, L. During published data on a different form of pustulosis, followed by P. Crocker and R. Sutton considered the disease to be branches of a common tree.
However, from the point of view of modern dermatology, acrodermatitis continua has the right to be called an independent nosological unit. This is confirmed not only by the specific localization of pustular eruptions, the supposed genesis of dermatosis, and the involution of primary elements. It was the description of the pathology clinic with a distal lesion of the skin of the extremities that gave the name “acrodermatitis” to a whole group of different skin diseases with a similar localization of the process.
Causes
The cause of dermatitis and the mechanism of its development are not fully understood. The most likely theory is trophoneurosis, which is based on a functional disorder of the autonomic nervous system (ANS) with a violation of tissue nutrition. The trophism of the skin is regulated by the ANS indirectly: humorally – by a mediator circulating in the blood (this is how the dermis itself is innervated) or by the diffusion of the neural secret of cells directly from the nerve fiber into the tissue (this is how the epidermis, completely devoid of blood vessels, is innervated). Nervous trophic disorder leads to metabolic imbalance, reduces tissue nutrition, causes visually noticeable manifestations on the skin.
Pathogenesis
The trigger of trophic changes in continua acrodermatitis is considered to be damage to the skin. In this case, on the one hand, a purely mechanical injury of nerve fibers occurs, interrupting the innervation of the epidermis and dermis, on the other hand, the injury site becomes an entrance gate for infection (microbe, fungus, virus), aggravating the “defect” of the nerve fiber, triggering the mechanism of the antigen-antibody reaction. In the area of direct contact of the antigen with the skin, as a result of damage to cell membranes, inflammation occurs, first exudative, leading to cell dystrophy, then proliferative, enhancing their reproduction, aimed at restoring the integrity of the skin. These processes become phases of clinical manifestations of acrodermatitis continua.
Classification
Acropustulosis is usually classified according to the intensity of skin changes, the nature of the elements of the skin rash. Clinically , the following forms of the disease are distinguished:
1. The typical form – begins with the tips of the fingers of the extremities, is characterized by the gradual spread of the rash to the back of the hands, feet:
- vesicular (exudative) – the phenomena of hyperemia prevail, against which bubble elements appear, followed by the formation of crusts;
- pustular (pustular) – a secondary infection joins, the transparent contents of the vesicles become cloudy, purulent, dries up with the formation of “fatty” crusts;
- erythematosquamous – characterized by polymorphism of rash elements: erythema, vesicles, pustules, papules, scales, crusts, excoriation;
- “dry” – in the lesion exclusively secondary elements of the rash: scales, crusts, cracks.
2. Abortive form – local rashes only on the first and second fingers, without spreading the process:
- vesicular (exudative)
- pustular (pustular).
3. Malignant form – total spread throughout the skin and mucous membranes with natural shortening of the distal extremities, onycholysis:
- erythematosquamous.
Symptoms
On the unchanged skin of the distal parts of the hands, less often – the feet, hyperemia with a bluish-purple hue appears. First, one finger is involved in the process, then the second, third, back surface. The skin of the fingers becomes swollen, tense, varnished; the nail rollers thicken, soreness appears when trying to bend the limb. This is followed by the precipitation of asymmetrically arranged primary elements: vesicles, pustules, crustal scales. Nails become cloudy, streaky striation appears, pus accumulates under the nail plate.
The affected surface of the fingers is strewn with small bubbles that transform due to the addition of a pyococcal infection into pustules. Vesicles, pustules burst, expose the erosive surface, shrink into crusts, scales, dry skin areas with cracks appear. Such a process of involution of rashes, when elements at different stages of their development are simultaneously located in the lesion, is specific for Hallopeau acrodermatitis, is called false (involutional) polymorphism.
Over time, the rash regresses with the phenomena of slight hyperpigmentation or, conversely, atrophy. Nail plates under the action of pyococci “dissolve”, disappear. It is very rarely possible to generalize the process with spread to the skin and mucous membranes. This is a malignant variant of the course with mutation (spontaneous shortening) of the fingers.
Diagnostics
The clinic of acropustulosis is quite specific for diagnosis. In unclear cases, pathomorphology helps. Histologically, the presence of Kogo pustules is noted, which “relates” acropustulosis to Tsumbush disease and herpetiform impetigo, but in fact emphasizes only their common affiliation to primary pustular skin diseases.
Differential diagnosis is carried out with various forms of pyoderma, pustular palmar-plantar psoriasis, local forms of During dermatitis, pyococcal eczema of the extremities, Andrews bacteroid.
Treatment
Starting treatment, first of all, sanitize foci of chronic infection, correct disorders of the neuro-endocrine system, metabolism. Depending on the clinical manifestations, severity, and prevalence of the process, retinoids, cytostatics, glucocorticoids, immunosuppressants, and anibiotic therapy are used. Prescribe iron preparations, vitamins A, C, phytin, phosphorus preparations that improve metabolic processes.
PUVA therapy is indicated, in severe cases – bucci rays, X-ray therapy. Externally, disinfectants (miramistin, Castellani paint), anti-inflammatory drugs with antibiotics and hormones are used. The prognosis is conditionally favorable due to short remissions, resistance to therapy.