Erythema annulare centrifugum (EAC) is a figurate erythema that has been postulated to be a hypersensitivity reaction to a foreign antigen. While infections, drugs, underlying systemic disease, malignancy, pregnancy, and blue cheese ingestion have occasionally been associated with EAC, in most cases, an etiologic agent is not identified.

EAC can occur at any age but tends to affect young or middle-aged adults. There is no sex or racial predilection. Idiopathic EAC is typically self-limited and spontaneous resolution is common. However, new lesions may continue to erupt while old lesions resolve.

In the superficial form of EAC, arcuate or annular plaques with a "trailing edge" of scale are seen on the trunk and proximal extremities. In the deeper form, also known as deep gyrate erythema, no scale is seen.

EAC may be asymptomatic or may be accompanied by pruritus.

While most cases of EAC are idiopathic, a number of agents have been reported to cause EAC-like lesions including piroxicam, penicillins, chloroquine and hydroxychloroquine, hydrochlorothiazide, spironolactone, cimetidine, phenolphthalein, amitriptyline, hydrochlorothiazide, salicylates, ustekinumab, rituximab, pegylated interferon alpha / ribavirin combination therapy, azacitidine, and anti-thymocyte globulin.

EAC in the setting of an underlying malignancy has been described in patients with lymphoproliferative malignancies (polycythemia vera, acute leukemia, chronic lymphocytic leukemia, Hodgkin lymphoma, non-Hodgkin lymphoma, multiple myeloma, myelodysplastic syndrome, histiocytosis), breast cancer, gastrointestinal cancer, lung cancer, prostate cancer, nasopharyngeal cancer, carcinoid tumor of the bronchus, and peritoneal cancer. The eruption may precede the diagnosis of occult malignancy.

Reported systemic disease associations include systemic lupus erythematosus, cryoglobulinemia, polychondritis, linear IgA disease, sarcoidosis, hypereosinophilic syndrome, hyperthyroidism, Hashimoto thyroiditis, Graves disease, and pemphigus vulgaris. Finally, infectious etiologies may include bacterial, viral, parasitic, and fungal agents.