Erythema

• Localized blanchable redness of skin or mucous membrane.
• Erythema and erythroderma will blanch because the color (“redness”) is due to increased blood flow, not leakage of blood into the skin, as in purpura.

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  Erythema on the upper chest and neck in dermatomyositis.

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  Eyelid erythema in a patient with dermatomyositis, appearing as a deep violaceous color.

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  A large erythematous, edematous plaque of cellulitis on the thigh.

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  Erythematous patch in Lyme disease.