Toxidermia

TOXIDERMIA, the name for various skin changes that occur as a result of poisonous substances entering the body. Such substances include various chemical preparations (for example, medicinal substances prescribed for internal administration, for subcutaneous, intramuscular and intravenous injections, for inhalations, for topical application to the skin or for rubbing in, etc.; further, chemical substances with which patients have to deal due to their profession, etc.), various food substances, bacterial toxins and auto-toxins, sera used for therapeutic purposes, etc. Thus, under the concept of T. in the broad sense of this word can be included an extensive area of dermatology up to rashes in various acute infectious diseases, up to various rashes that result from an allergic condition of the skin in relation to various ingredients entering the body. At the same time, it should be borne in mind that the agents causing toxidermia are by no means always poisons in the true sense of this word, which is especially clearly evident in cases where the appearance of T. from non-poisonous preparations depends on the idiosyncrasy of the individual, mono- or polyvalent sensitization or an allergic condition of the skin. The skin manifestations in T. can have a diverse character of rash elements (spotted or diffuse erythematous redness up to general dermatitis, vesicular, bullous, papular, urticarial elements, sometimes of a hemorrhagic nature), which depends both on the nature of T. and on the intensity of its degree. T. from external causal factors are closely related to dermatitis or eczema from the same causes. Artificial dermatitis require for their occurrence a skin-irritating agent, and the skin phenomena are limited only to the site of the agent's action, not spreading to other parts of the body and disappearing fairly quickly with indifferent therapy or without it; artificial eczema in predisposed individuals arises from the action of an agent of negligible concentration, which does not cause inflammatory phenomena in the skin in healthy subjects; in T., however, inflammatory phenomena can spread far beyond the site of the agent's action, sometimes to extensive areas of the body with a symmetrical arrangement of the rash, which may indicate the action of the harmful agent through the bloodstream or the nervous system. External agents of T. can be the most diverse preparations (various medicinal and chemical substances used as cosmetic means: iodoform, tar preparations, chrysarobin, etc., various elixirs for gargles, makeup, hair dyes, etc.; various chemical substances used in factory and factory enterprises: paints, varnishes, lubricants, essential oils, etc.; products of the plant and animal world), and in some cases it is difficult or even almost impossible to draw a line between T. from an external cause and eczema from the same cause. Occupational T. constitute an extensive area and arise as a result of various agents used in various industries (acids, alkalis, paints, varnishes, turpentine, gasoline, tar, various gaseous substances, etc.). Clinical manifestations in T. from internal causes come down to more or less abundant eruptions of erythematous, papular, vesicular, urticarial elements, sometimes in the form of single, fixed foci, sometimes in the form of spreading or nodular formations, and sometimes also in the form of gangrenous foci of lesions. From medicinal preparations, T. phenomena can be caused by various mercury, arsenic, iodine, bromine preparations, antipyrine, luminal, balsamic preparations, etc. From food products, T. can be caused by stale products (meat, fish), as containing ptomaines, various canned goods and salted foods, cheeses and spices, especially of poor quality or subjected to fermentation or decomposition. In individuals with idiosyncrasy to certain food products, T. phenomena can develop even with quite wholesome products. T. from the use of various sera - see Serum sickness. - Treatment of T. is mainly reduced to eliminating the causal factor and symptomatic therapy. In individuals with mono- or polyvalent sensitization, an attempt can be made at desensitization by neptunotherapy, intravenous infusions of sodium thiosulfate, autohemo- or autoserotherapy, etc.