SAT-210 Autoimmune Progesterone Dermatitis: A Rare Case Report in a Young Woman with Chronic Dermatitis

Back ground: Autoimmune progesterone dermatitis (APD) or progesterone hypersensitivity (PH) is a rare hypersensitivity reaction to progestogen that exclusively occur in women of childbearing age of which is the underlying mechanism remains not well understood. Clinical case: A 44 years old lady was referred to our endocrine outpatient clinic by her dermatologist for treatment of a recently diagnosed autoimmune progesterone dermatitis. She was initially evaluated for a skin rash that started during the second trimester of her second pregnancy in 2009. Her initial diagnosis was pregnancy induced eczema which was treated with topical steroid with no significant improvement. Her rash worsens after delivery and had persisted since then. She failed chronic systemic steroid treatment and multiple immunosuppressive medications over the years. She had regular menstrual period since her menarche at age of 11 years old. She was on oral contraceptive medication prior to her second pregnancy which she resumed after delivery. She then switched to IUD. Her rash typically gets worse 7-10 days before the onset of her menstrual period with some improvement after her period. Her initial clinical exam showed erythematous papules over her extensor elbows, thighs and genital area with scattered eczematous excoriated plaques over her extremities and trunk. She underwent skin patch test which showed that she is allergic to class A, B, and D1 steroids PH was suspected based on her history and confirmed by a positive progesterone skin test. She was referred to reproductive endocrinology for consideration of ovulation suppression using GnRH agonist. Conclusion: APD is a rare hypersensitivity reaction that can be triggered by endogenous progesterone (menses, pregnancy) or exogenous progestin (OCP, IUD, IVF) exposure. Women between menarche and menopause can be affected with the average age of onset to be in the third decade of life. The underlying mechanism is not well known with several hypotheses being postulated (e.g hypersensitivity reaction type I and IV, hormone cross reactivity and autoimmunity) Clinical presentation is variable and can range from mild dermatitis to life threatening anaphylaxis with some extra dermal manifestations have been described. Detailed history taking is the key to diagnosis as the most consistent features is the presentation of symptoms during the luteal phase of the menstrual cycle. The goal of treating APD is to suppress ovulation which can be achieved by the use of GnRH agonist, selective estrogen receptor modulator or oophorectomy. Progesterone desensitization has been tried in women desiring pregnancy.