Autoimmune progesterone dermatitis manifested as erythema annulare centrifugum: Confirmation of progesterone sensitivity by in vitro interferon-gamma release.

Autoimmune progesterone dermatitis was manifested as deep-type erythema annulare centrifugum. Sensitivity to progesterone was studied in vivo by means of intradermal and patch tests, which revealed immediate-type and delayed-type hypersensitivity, respectively. Sensitivity to progesterone was further confirmed in vitro by results of an interferon-gamma release test, which imply a possible role for T(H)1-type cytokines in autoimmune progesterone dermatitis.