A case of autoimmune progesterone dermatitis misdiagnosed as allergic contact dermatitis.

Autoimmune progesterone dermatitis is a rare autoimmune response to endogenous progesterone that usually occurs in fertile females. Cutaneous or mucosal lesions develop cyclically during the luteal phase of the menstrual cycle when progesterone levels are elevated. Symptoms usually start 3-10 days before menstruation and resolve 1-2 days after menstruation ceases. We report the case of a 48-year-old woman with intermittent eczematous skin lesions of the legs, forearms, and buttocks. She was diagnosed with allergic contact dermatitis, and topical steroids were prescribed. Her skin eruptions waxed and waned for 6 years and were associated with her menstrual cycle. We performed an intradermal test using progesterone, which was positive, and prescribed gonadotropin-releasing hormone analogues monthly for 3 months. The patient's skin lesions improved, confirming the diagnosis. Autoimmune progesterone dermatitis should be included in the differential diagnosis of recurrent eczema that is refractory to treatment in women of child-bearing age.