erythema(redirected from erythema iris)
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erythema(ĕr'əthē`mə), more or less diffuse redness of the skin due to concentration of an abnormally large amount of blood within the small vessels of the skin (hyperemia), as in burns. Erythema nodosum is often associated with systemic diseases such as tuberculosis and rheumatic fever. Tender, bright red, slightly elevated nodules develop along the shins. Erythema multiforme can have a number of causes, including viral and bacterial infection, chronic disease of the visceral organs, or allergic reactions to drugs.
reddening of the skin caused by the dilatation of blood vessels. Erythema sometimes occurs by reflex action and disappears quickly, for example, when one feels ashamed or angry. With inflammation, the condition lasts longer. It appears as a result of exposure to chemicals and physical factors (friction, heat, cold, ultraviolet radiation) and in some infectious diseases (scarlet fever, measles, erythema infectiosum) and skin diseases (dermatitis). It also occurs as a result of poisoning and disturbances in blood circulation.