Two cases of autoimmune progesterone dermatitis. Immunohistochemical and serological studies.

Two cases of autoimmune progesterone dermatitis are reported. The patients developed recurrent pruritic erythematous and edematous eruptions on the extremities, trunk or face, with occasional vesicles on the palms and soles. The eruptions appeared 7 to 10 days prior to their menstruation and persisted for several days. They showed immediately positive skin tests with 0.1 mg/ml and 0.2 mg/ml of aqueous progesterone suspension, respectively. The patients had IgG serum factor which bound rat corpus luteum. Positive indirect basophil degranulation tests against progesterone were demonstrated in both patients. Circulating autoantibodies to patients' own progesterone may cause or modulate the intermittent eruptions of the disease.