Autoimmune progesterone dermatitis (APD) is a hypersensitivity reaction to exogenous and/or endogenous progesterone in women. There is often a significant delay between the onset of the condition and the diagnosis.
The condition may present in 3 setting:
(1) recurring skin lesions during the luteal phase of the menstrual cycle
(2) skin lesions during pregnancy
(3) skin lesions in association with exogenous progesterone
Skin changes may include urticaria, angioedema, eczema, fixed drug eruption, or vesiculobullous eruptions. Some patients may experience anaphylactoid reactions. Some patients may also experience pruritus.
If the reaction is to exogenous progesterone, the rash may be worse during the peak concentration of progesterone.
The patient may fail to respond to antihistamines or steroid therapy.
The diagnosis is supported by
(1) the presence of symptoms after intradermal progesterone testing.
(2) clinical improvement after suppression of the luteal phase of the menstrual cycle or discontinuing progesterone exposure.
