Noninfectious dermatoses

Allergic dermatoses are found quite often and are mainly due to the population's contact with plants and their products. They are referred to as plant dermatitis (forest, jungle). The most frequently observed mango, pineapple, primula, polysander, beech, tobacco, caused by poison ivy, etc., phytodermatites.

Tropical flat lichen

The disease, which is characterized by the appearance on the open areas of the skin rashes, clinically and morphologically similar to the classic red flat lichen. The onset of the disease is associated with the use of antimalarial drug athebrin, high air temperature, prolonged light day, increased solar radiation, alimentary dystrophy (children), beriberi, helminth invasions, bread baking with tandoor. The disease usually occurs in the summer months. Affected face (forehead, cheeks, lips), open areas of the neck, the back surfaces of the hands and lower third forearms, the rear of the feet. Possible damage to the oral mucosa by the type of leukoplakia, the formation of bubble-erosive lesions, stomatitis. The lesions on the skin are practically the same as typical rashes of red flat lichen (with the presence of a Wickham mesh). By the winter period, inflammation, itching regress; persistent hyperpigmentation remains on the rash ground.

Treatment: exclude the ingestion of athebrin or replace it with another antimalarial drug. It is necessary to protect the skin from increased air temperature, solar radiation. Appointed hyposensitizing and other symptomatic means.

Prognosis: in most cases, favorable, but relapses are possible.

Eczema

Typical is a weak exudative reaction (microveiculation, mocclusion), more reminiscent of neurodermatitis, ie, the "dry" course of the eczematous process.

[1], [2], [3]

Neurodermatitis

It differs in its tendency to disseminate rashes and weak their lichenification.

Psoriasis

In the tropics is observed less often. More often there are infiltrative forms of dermatosis in the form of single, "on duty" dry plaques on the places of favorite localization. Isomorphic reaction is not typical. To confirm the diagnosis, histological examination is often required.

Erythematous

Chronic skin forms of the disease are much less common (despite hyperinsolation) than in countries with a temperate and cold climate. Systemic lupus erythematosus is diagnosed somewhat more often than in European countries.

[4], [5], [6], [7], [8]

Tropical itchy dermatosis

Temporary scrapes - the appearance of itchy small serous papules on the extensor surfaces of the extremities, which are subsequently covered with serous-hemorrhagic crusts. The process can take up to several months with influenza-like phenomena. Weighed down the course of the disease helminthic invasions and other associated diseases.

Tropical sweating is a temporary dermatosis associated with clogging of sweat glands (horny scales, sebum, dust, etc.) at a different level of their occurrence in the skin when working in hot conditions: from transparent bubbles filled with sweat until their pustulization. The process is more often localized in the elbows and knee folds, on the chest, abdomen, other areas, rarely - on the face. It disappears independently under climate change.

Tropical pomfolix - is seasonal (summer) in nature. The phenomena of sweating occur only on the palms and soles of the feet, the lateral surfaces of the fingers. Intraepidermal vesicles are opened, eroded, then quickly epithelized, without causing subjective complaints. Complications - eczematization, pustulization, abscessing.

Phlebotodermia is a common dermatosis that occurs after repeated human bites by mosquitoes and sensitization of the body to the secretion of salivary glands of phlebotomy. In open areas of the body, shortly after the attack of mosquitoes, roseoles with punctate hemorrhage appear in the center, then turn into itchy papules, often covered with vesicles. Watery and papulo-bullous reactions are possible. The appearance of elements is accompanied by excoriations. After the attack phlebotomus, the process usually gradually subsides. Depending on the degree of sensitization, the presence of concomitant diseases with repeated attacks of mosquitoes, dermatosis can take a widespread recurrent nature with the formation of pruriginous nodular elements (up to the pea), various pyo-coccus eruptions. The disease can be delayed up to several months and longer. In some cases, it is necessary to conduct active therapy, including systemic use of corticosteroids.

Harara (endemic multi-form urticaria) - seasonal (summer) itching dermatosis associated with repeated human bites by separate mosquito species. It is more common in the Arab countries, both from the arrived people, and from the local population (of both sexes and different ages). It is observed on open areas of the body, especially in the lower third of the shin and the rear of the foot. Polymorphism of the rash is characteristic: papulo-blisters, serous papules, erosion, serous-hemorrhagic crusts, pyococcal elements. Possible general toxic effects. With the passage of time (1-3 months), the process acquires a "dry" character, gradually subsides, temporary hyperpigmentation is formed at the sites of the rash. In some cases, the disease can be delayed up to 1-2 years (chronic harar) with a clinic of dry itchy nodular rashes and lichenification phenomena.

Tropical Bullous Dermatosis

True pemphigus in tropical countries is less common than in regions with a temperate and cold climate.

To tropical bullous dermatoses include the Brazilian exfoliative pemphigus (BEP) and onyalai (onyalai).

BEP - without a prodrome on the face, chest, less often in other areas there are blisters that are complicated by the piococcal process, eczematism, sometimes with verrucous sprouting, focal dyschromia. Nikolsky's symptom is positive. The mucous mouth is not affected. Severe course is observed with fulminant (often ends lethal) and acute forms of BEP (signs of severe intoxication, extensive erosion and areas of impetigo).

Symptomatics is less pronounced in the subacute form of the disease. Chronic BEP has a long course and is accompanied by clinical polymorphism involving the osteoarticular system, teeth, muscle atrophy, mammary glands and other manifestations.

Onyalai - a serious disease of hot countries with a clinic of bullous and hemorrhagic rashes on the skin and mucous membranes. Characterized by a systemic hemorrhagic syndrome, thrombocytopenia, a severe general condition and the formation of large blisters on the oral mucosa with suppurative deposits reminiscent of aphthae. The prognosis is unfavorable in the absence of intensive therapy, including corticosteroids, blood transfusion, blood substitutes.

Neoplasms of the skin

There is no unanimous opinion on the greater frequency of benign and malignant skin tumors in a hot climate. There are data on rare cases of skin cancer among the population of China, Japan, Arab countries, and Negroes. Cancer of the penis is not detected in the nationalities, which traditionally produced excision of the foreskin. In Africans, skin cancer develops mainly on the sites of a chronic inflammatory process, ulcers, wounds. Vascular nevi in individuals of the black race are often poorly visualized, and hairy nevi are less common than in Europeans. Features of the profile of benign neoplasms (warts, pointed cannonoloma, fibromas, etc.) is not noted.

Lack of vitamins

Hypovitaminosis A occurs often enough, the damage to the skin is common or universal. Well amenable to vitamin A correction.

Exfoliative cheilitis (associated with ariboflavinosis) is characterized by torpidity to therapy.

Venereal diseases and endemic treponematosis

Venereal diseases

In people living in hot climates, the clinical manifestations and diagnosis of syphilitic infection have some peculiarities:

• roseola on dark skin is poorly visualized;
• in the presence of ulcerative chancre, lymphadenitis is moderately expressed;
• in later stages, articular knots (elbows, knees) occur;
• when establishing the diagnosis of syphilis, it is necessary to take into account the possibility of false positive reactions associated with other infectious diseases (leprosy, malaria, helminthiases, etc.) and drug use.