Autoimmune progesterone dermatitis presenting as fixed drug eruption

Abstract

Autoimmune progesterone dermatitis (APD) is a rare disorder that presents as recurrent cyclical cutaneous eruptions during the premenstrual period when progesterone level is elevated. It does not have a specific cutaneous manifestation of its own and presents with a multitude of common cutaneous conditions, thus making it a diagnostic challenge. We describe the case of a young woman who presented with a hyperpigmented patch on her left thigh, over which she developed recurrent erythema, pain and itching, starting 2\u2009days before her menstrual cycle and resolving within 2\u2009days after menstruation. Intradermal progesterone sensitivity test was positive. Histopathology of hyperpigmented patch showed features of fixed drug eruption. A diagnosis of APD presenting as fixed drug eruption was made. She was treated with oral contraceptive pills with significant improvement. This case has been reported because of its rarity and to highlight the clinical implications this condition can pose if diagnosis is not sought timely.