One cousing said he had something called well's syndrome (eosinophilic cellulitis?). What causes it?

Wells Syndrome. Wells syndrome (eosinophilic cellulitis) is an uncommon condition of unknown etiology. The presentation usually involves a mildly pruritic or tender cellulitis-like eruption with typical histologic features characterized by edema, flame figures, and a marked infiltrate of eosinophils in the dermis. Papular and nodular eruptions at the clinical presentation have also been reported.

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What is well's syndrome (eosinophilic cellulitis)?

Mimics cellulitis. It is an inflammatory reaction to some type of antigen that causes a reaction that mimics cellulitis. Limited to the dermis and epidermis it is treated usually with steroids, oral or topical, not with antibiotics. Treatment often delayed as initial assumption is that antibiotics are indicated which is not the case.