TOXIDERMIAS (toxidermia; Greek toxikon poison + Greek derma skin; these.: toksikodermiya, dieback toxic) — the diseases of skin arising in response to allergic or toxic influences of chemicals are more rare than the foodstuff which got to an organism.
An etiology and a pathogeny
In development of T. the major role is played by pharmaceuticals (antibiotics, streptocides, barbiturates, analgetics, vaccines, vitamins of group B, etc.), the foodstuff, production and household chemical substances which got to an organism, as a rule, through respiratory tracts are more rare. Pharmaceuticals can cause T also. at their intravenous, intramuscular and hypodermic administration, sometimes at external use (as a result of dermal absorption).
Main mechanism of development of T. — allergic (see. Medicinal allergy , Food allergy ). Less often toxic reaction meets (e.g., on substandard food stuffs). Sometimes in a pathogeny of T. plays a role idiosyncrasy (see), e.g., to quinine.
Nek-ry researchers carry T. to allergic dermatitis that it is impossible to recognize correct (see. Dermatitis ), since at dermatitis the exogenous factor affects directly skin.
T. arise, as a rule, sharply and are characterized more often by emergence on skin of the disseminated symmetric rash presented spotty (tsvetn. fig. 5), papular, knotty (see. Erythema knotty ), vesicular or papulovezikulezny, violent (tsvetn. fig. 6), pustular or papulopustulezny pruritic elements. In some cases visible mucous membranes are involved in process. Sometimes it is limited to damage of mucous membranes, napr, at mercury stomatitis (see).
Spotty T. (tsvetn. fig. 5) are shown by hl. obr. hyperemic spots, is more rare hemorrhagic (purple) and pigmental (e.g., the toxic melanoderma caused by influence of metacycline, petroleum hydrocarbons or black coal). Hyperemic spots are located separately from each other (a rozeolezny toxidermia) or merge in extensive an erythema up to universal (erythrosis), can be ring-shaped. At permission they are shelled. In case of damage of palms and soles full rejection of a corneous layer of epidermis is observed. Quite often the peeling develops only in the center of rozeolezny spots and reminds a wedge, a picture pink depriving (see. Deprive pink). The Krupnoplastichesky peeling reminds sometimes scarlet fever — scarlatiniform T. (see Scarlet fever). Vesicular T. in some cases it is limited to damage of palms and soles and shown by disgidrotichesky bubbles (see Eczema). Pustular and papulopustulezny (acne) T. are usually connected with effect of halogens — bromine (see. Bromoderma ), iodine (see Yododerm), chlorine, fluorine, but also reception of rat anti-acrodynia factors and B12, an isoniazid, phenobarbital (luminal), drugs of lithium, etc. can be their cause. Papular T., developing as a result of long reception of Chingaminum, quinine, PASK, a derivative fenotiazin, levamisole, streptomycin, tetracycline, drugs of gold, mercury, iodine, sometimes remind red flat deprive (see. Deprive, red flat ). T. it can be shown in the form of an exudative mnogoformny erythema, including in the form of its version — Stephens's syndrome — Johnson (see. Erythema exudative mnogoformny ).
The special form is represented by the fixed T., developing as a result of reception of streptocides, barbiturates, salicylates, antibiotics, Chlorali hydras, antihistaminic drugs, etc. It is characterized by emergence of one or several roundish bright red large (to dia. 2 — 5 cm) the spots soon getting especially in the central part, a cyanotic shade (tsvetn. fig. 7), and at disappearance of the inflammatory phenomena leaving permanent pigmentation of a peculiar flaky-brown color. Against the background of spots bubbles are quite often formed. At the subsequent reception of the corresponding medicine process recurs on the same places, strengthening pigmentation, and gradually arises also on other sites of skin. The fixed T. it is often localized on generative organs and a mucous membrane of an oral cavity. In process of removal of allergen or toxicant from an organism there is permission of skin rash.
In hard cases internals can be involved in process. On the first place among damages of internals on gravity of the forecast and difficulty of intravital diagnosis there is allergic myocarditis (see). Sometimes medicinal allergic reaction is shown in the form of an acute epidermal necrolysis (see. Necrolysis epidermal toxic ), a medicinal lupus erythematosus (see. Lupus erythematosus ), edges it is quickly allowed after cancellation of medicine, or in the form of an allergic vasculitis (see. Vasculitis of skin ).
the Diagnosis is established on the basis of the anamnesis, data by a wedge, pictures, and also diagnostic tests, including skin (see. Skin tests), for confirmation etiol. roles of the suspect of chemical substance. The most convincing results are yielded provocative tests (see). So, if T. resulted from reception of medicine inside, and test should be carried out orally, appointing once minimum therapeutic dose of the suspect of drug. In case of a recurrence of T. test is estimated as positive. Skin tests at the same time often are negative. At the fixed medicinal T. they are always negative if are not carried out on places of the resolved centers. It is necessary to approach provocative tests carefully: to appoint only them after permission of rash, to avoid use to the persons who transferred T. in a severe form, in the presence in the anamnesis of an allergy.
In addition to provocative tests of in vivo, for definition of sensitivity of an organizkhm to a certain allergen use diagnostic tests of in vitro — reaction of a leykotsitoliz, or the PPN test, (see. Leukocytic tests ), the test of degranulation of basophiles (see. Basphilic test ) and blastotransformation of lymphocytes (see), thrombocytopenic test (see), etc.
Treatment of T. provides first of all cancellation on an organism etiol. factor: cancellation of the accepted pharmaceuticals, release from the work connected with production vrednost, an exception of contacts with household chemical substances. Appoint a sparing diet, and also diuretics — themisal (Diuretinum) and laxatives — sodium sulfate for the purpose of removal of allergen or toxicant from an organism. To the patient parenterally enter Haemodesum, solutions of chloride or a gluconate of calcium or sodium thiosulphate, and also antihistaminic drugs, vitamin P and ascorbic to - that. At development of the general phenomena with fervescence of the patient hospitalize in a hospital, appoint glucocorticoid hormones, carry out hemosorption (see), etc. Outwardly apply the antipruritic shaken-up suspensions, cold creams or corticosteroid ointments, aerosols. Apply antibacterial lotions or vlazhnovysykhayushchy bandages the continuous becoming wet centers.
Forecast favorable, if T. is not followed by severe damage of internals.
Prevention hypersensitivity of an organism consists in an exception of contact with those chemical substances, foodstuff, to the Crimea; it is not necessary to appoint the pharmaceuticals causing allergic reactions in the past.
See also Vaccinal rashes .
Bibliography: Differential diagnosis of skin diseases, under the editorship of. A. A. Stud-nitsina, M., 1983; Kormeyn P. X. and And since and r S. S. Immunologiya and diseases of skin, the lane with English, M., 1983; Yu. F. Queens and P and l t and e N to about L. F. Medicamentous toxidermias, Minsk, 1978, bibliogr.; A drug disease, under the editorship of G. Mazhdrakov and P. Popkhristov, lane with Bol, Sofia, 1976; Goring H. - D. u. Raith L. Immun-diagnostik in der Dermatologie, Lpz., 1981; Sonnichsen X. u. Z a b e 1 R. Hautkrankheiten, Diagnostik und Thera-pie, S. 18, Lpz., 1976.
V. I. Samtsov; V. V. Vladimirov (tsvetn. fig.).