Erythema

: A redness of the skin resulting from inflammation, for example, as caused by sunburn.

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Redness due to capillary dilation. [G. e., flush]

- e. ab igne a reticulated, pigmented, macular eruption that occurs, often on the shins, in bakers, stokers, and others exposed to radiant heat. SYN: dermatitis calorica, e. caloricum, toasted shins.

- acrodynic e. SYN: acrodynia (2).

- e. annulare rounded or ringed lesions.

- e. annulare centrifugum a chronic, expanding, recurring erythematous eruption consisting of small and large annular lesions, with a scant marginal scale and central clearing, usually of unknown cause. SYN: e. figuratum perstans.

- e. annulare rheumaticum a variant of e. multiforme associated with rheumatic fever.

- e. arthriticum epidemicum SYN: Haverhill fever.

- e. caloricum SYN: e. ab igne.

- e. chronicum migrans a raised erythematous ring with advancing indurated borders and central clearing, radiating from the site of a tick bite and persisting for 2–16 weeks; the characteristic skin lesion of Lyme disease, due to the spirochete Borrelia burgdorferi, which may be identified by PCR in biopsies.

- e. circinatum e. multiforme in which the lesions are grouped in more or less circular fashion.

- cold e. rash characterized by redness and itching, brought on by exposure to cold.

- e. dyschromicum perstans variously sized gray or red, slightly elevated macular lesions that tend to coalesce on the trunk and proximal extremities, commonly in dark-skinned Latin Americans; of unknown cause. SYN: ashy dermatosis.

- e. elevatum diutinum a rare chronic symmetrical eruption of flattened nodules of a pinkish or purplish color, occurring in plaques on the buttocks; Achilles tendons; and extensors of wrists, elbows, and knees, becoming fibrotic and finally scarring. Early lesions show necrotizing vasculitis with fibrinoid or lipid deposits in vessel walls.

- e. exfoliativa SYN: keratolysis exfoliativa.

- e. figuratum perstans SYN: e. annulare centrifugum.

- e. gyratum e. circinatum in which the various ringed lesions overlap each other.

- e. induratum recurrent hard subcutaneous nodules that frequently break down and form necrotic ulcers, usually on the calves and less frequently on the thighs or arms of middle-aged women; they are associated with erythrocyanotic changes in cold weather; although microscopically granulomatous and necrotizing, the lesions are sterile; but tuberculin skin tests are usually positive and polymerase chain reaction amplification is frequently positive for Mycobacterium tuberculosis complex DNA. SYN: Bazin disease, nodular tuberculid.

- e. infectiosum a mild infectious exanthema of childhood characterized by an erythematous maculopapular eruption, resulting in a lacelike facial rash or “slapped cheek” appearance. Fever and arthritis may also accompany infection; caused by Parvovirus B 19. SYN: fifth disease.

- e. intertrigo intertrigo.

- e. keratodes keratodermia with an erythematous border.

- macular e. SYN: roseola.

- e. marginatum a variant of e. multiforme seen in rheumatic fever; occasionally has a configuration to suggest the designation e. migrans (geographic tongue).

- e. multiforme an acute eruption of macules, papules, or subepidermal vesicles presenting a multiform appearance, the characteristic lesion being the target or iris lesion over the dorsal aspect of the hands and forearms; its origin may be allergic, including drug sensitivity, or it may be caused by herpes simplex infection; the eruption, although usually self-limited ( e.g., multiforme minor), may be recurrent or may run a severe course, sometimes with fatal termination ( e.g., multiforme major or Stevens-Johnson syndrome).

- e. multiforme bullosum SYN: Stevens-Johnson syndrome.

- e. multiforme exudativum SYN: Stevens-Johnson syndrome.

- e. multiforme major SYN: Stevens-Johnson syndrome.

- necrolytic migratory e. an erythematous, scaling, and sometimes bullous and erosive dermatitis occurring irregularly in plaques chiefly on the lower trunk, buttocks, perineum, and thighs; associated with weight loss, anemia, stomatitis, and elevation of plasma glucagon in islet cell tumor (glucagonoma) of the pancreas. SEE ALSO: glucagonoma syndrome.

- e. neonatorum SYN: e. toxicum neonatorum.

- e. nodosum a panniculitis marked by the sudden formation of painful nodes on the extensor surfaces of the lower extremities, with lesions that are self-limiting but tend to recur; associated with arthralgia and fever; may be the result of drug sensitivity or associated with sarcoidosis and various infections. Deep biopsies show a septal panniculitis with infiltration by lymphocytes and scattered multinucleated giant cells. SYN: nodal fever.

- e. nodosum leprosum an acute type of lepromatous reaction with generalized systemic involvement and tender deep cutaneous and subcutaneous nodules of the face, thighs, and arms; usually seen in undiagnosed, untreated, or neglected cases of leprosy. Immune complexes and scanty, fragmented lepra bacilli may be seen in the lesions.

- e. nodosum migrans SYN: subacute migratory panniculitis.

- e. nuchae SYN: Unna nevus.

- e. palmare hereditarium [MIM*133000] a hereditary condition, which may be precipitated by pregnancy, characterized by asymptomatic symmetrical redness of the palms; autosomal dominant inheritance. SYN: Lane disease.

- e. papulatum the papular form of e. multiforme.

- e. paratrimma e. due to stasis over pressure points.

- e. pernio SYN: chilblain.

- e. perstans probably a chronic form of e. multiforme in which the relapses recur so persistently that the eruption is almost permanent.

- scarlatiniform e., e. scarlatinoides an erythematous macular eruption accompanied by slight constitutional symptoms and followed by desquamation.

- e. simplex blushing or redness of the skin caused by a toxic reaction or a neurovascular phenomenon.

- e. solare SYN: sunburn.

- symptomatic e. a general term applied to various erythemas associated with systemic disease, fevers, allergic states, etc.

- e. toxicum an innocuous, self-limited rash of unknown cause that occurs in newborn infants.

- e. toxicum neonatorum a common transient idiopathic eruption of e., small papules, and occasionally pustules filled with eosinophilic leukocytes overlying hair follicles of the newborn. SYN: e. neonatorum.

- e. tuberculatum e. multiforme in which the papules are of large size.

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er·y·the·ma .er-ə-'thē-mə n abnormal redness of the skin due to capillary congestion (as in inflammation)

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n.

flushing of the skin due to dilatation of the blood capillaries in the dermis. It may be physiological or a sign of inflammation or infection. Erythema nodosum is characterized by tender bruiselike swellings on the shins and is often associated with streptococcal infection. In erythema multiforme the eruption, which can take various forms, is characterized by so-called target lesions that may be recurrent and follow herpes simplex infection. Erythema ab igne is a reticular pigmented rash on the lower legs or elsewhere caused by persistent exposure to radiant heat.

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er·y·the·ma (er″ə-theґmə) [Gr. erythēma flush upon the skin] redness of the skin produced by congestion of the capillaries. erythematous adj