Wells syndrome (eosinophilic cellulitis): Proposed diagnostic criteria and a literature review of the drug-induced variant.

Background: Wells syndrome is an uncommon inflammatory dermatosis first described in 1971 by Wells. The clinical eruption is characterized by varying morphology and severity and usually follows a relapsing remitting course. The majority of the reported cases are of unknown etiology, drug induced Wells syndrome has rarely been reported. A literature search using MEDLINE was performed. We recorded the features of our case and of the additional cases of drug induced Wells syndrome in the literature.

Main observations: Including our case there are 25 cases of drug-induced Wells syndrome reported. Causative drugs include antibiotics, anticholinergic agents, anaesthetics, non-steroidal anti-inflammatory agents, thyroid medications, chemotherapeutic agents, thiomersal containing vaccinations, anti-tumor necrosis factor agents and thiazide diuretics.

Conclusions: To the authors knowledge this is the first reported case of drug-induced Wells syndrome from thiazide diuretics. The diagnosis of Wells syndrome is often controversial and we propose a set of diagnostic criteria.