What is Autoimmune progesterone dermatitis?

The rash generally appears during the second half of the menstrual cycle when levels of the hormone, progesterone, begin to rise and it recedes shortly after menstruation. Although the exact underlying cause of APD is not well understood, it is believed to involve an abnormal immune reaction (autoimmune response) triggered by a woman's own progesterone.

As per the severity of the condition, treatment may include topical (applied to the skin) medications, systemic corticosteroids, hormone therapy to suppress the production of progesterone, and/or surgical removal of the ovaries.

Symptoms

The several types of skin rashes observed in women with autoimmune progesterone dermatitis include

• Hives

• Erythema multiforme

• Swelling beneath the skin (angioedema)

• Eczema-like rash

• Annular erythema

• Mouth sores

In rare circumstances, APD may progress to progesterone-induced anaphylaxis.

Cause

The exact primary cause of autoimmune progesterone dermatitis is not completely understood. Most scientists believe that the cyclic rash occurs when an abnormal immune reaction (autoimmune response) is triggered by increasing levels of the hormone, progesterone.

The proposed theory suggests that high levels of progesterone may lead to a heightened response to another allergen.

Diagnosis

The diagnosis of APD is normally based on clinical history, including the timing of symptoms around the menstrual cycle and an indication of a skin reaction to progesterone.

For diagnosis in most cases, progesterone is introduced by a skin prick or needle injection into either the skin (intradermal) or muscle (intramuscular). Test is considered positive if a skin reaction called a 'wheal-and-flare' develops and lasts for a period of 24-48 hours.



Other diagnostic tests used for detecting this medical condition include eosinophil count, quantitative measurements of immunoglobulin and complement as well as checking levels of hormones such as luteinizing hormone, progesterone, and estradiol.

Treatment

The treatment or control of symptoms of autoimmune progesterone dermatitis (APD) depends on the condition of the patient and severity. Mild cases might be easily treated with the use of medications such as antihistamines and/or corticosteroids.

Antihistamines are a class of drugs which help to relieve the allergic symptoms. Corticosteroids are steroids hormones that help in treating inflammation in the case of APD.

Most methods of treatment aim at temporarily suppressing ovulation. This is made possible use of various medications which include conjugated estrogen, ethinyl estradiol, tamoxifen, and danazol.

Gonadotropin-releasing hormone agonists have in addition proved to successfully manage APD, however as these medications can trigger the symptoms of menopause, they might not be recommended for pre-menopausal patients. Progesterone desensitization, in which increasing doses of progesterone are administered using a vaginal suppository, has been reported as a successful treatment in one of the research studies.

For severe cases in which the above treatment options do not produce the desired effect, surgical removal of ovaries or oophorectomy is recommended in that case.