Erythema is characterized by redness of the skin. This redness is caused by increased blood flow to the affected area. The specific appearance of erythema can vary depending on the underlying cause, but redness is a consistent feature.
Several sources highlight different aspects of erythema, depending on the specific type:
Types and Characteristics of Erythema:
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Erythema Multiforme: This is an inflammatory reaction showing symmetrical, red, raised skin areas. These areas are often described as "target" or "iris" lesions and can appear all over the body, particularly on the fingers and toes. Merck Manual Professional Edition, AAFP, Johns Hopkins Medicine.
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Erythema Migrans: The appearance of this lesion, often the first sign of Lyme disease, varies depending on age and sex. PubMed
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Erythema Nodosum: This condition presents as nodules, often on the legs, that can merge into larger plaques. JAMA Dermatology, PubMed, AAFP.
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Erythema Gyratum Repens: This is a rare paraneoplastic rash with a characteristic appearance, often associated with cancers like lung, esophageal, and breast cancer. PMC
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Psoriasis: While not solely erythema, psoriasis includes sharply demarcated, scaly, erythematous plaques as a key characteristic. PMC
In summary, while the precise appearance may differ across various types of erythema, the common thread is the presence of redness in the affected skin area.
