Herpes Gestationis

Key Points
Rare skin condition which affects pregnant women
Autoimmune condition in which the immune system attacks the area between the dermis and epidermis. The target for the self antibodies is BPAG 2 (bp 180).
Initially consists of red, itchy bumps around the navel, which then blister and spread to other areas

Pemphigoid gestationis, also known as herpes gestationis, is a rare skin condition which affects pregnant women. The condition initially consists of red, itchy bumps which form around the navel. Lesions then spread to other areas, including the upper torso, back, buttocks, and arms. After 2-4 weeks, large blisters form in affected areas. In some cases affected areas may not blister, but will have large plaques.

Pemphigoid gestationis is an autoimmune condition in which the immune system attacks the membrane between the dermis and epidermis (the midle and top layer of skin). The antibodies attack a bonding component between layers known as BPAG2 causing bond breakage, inflammation, and the eventual bulla (blister) formation. While it typically appears during the second or third trimester of pregnancy, it may present throughout pregnancy in some cases. In the majority of cases, the condition resolves within a few days after giving birth, though flare-ups often occur around the time of delivery. In rare cases, the condition may persist for months or years after delivery.

Differential Diagnosis (Other conditions with similar appearance)
Bullous pemphigoid
Cicatricial pemphigoid
Linear IgA dermatosis
Pruritic urticarial papules and plaques of pregnancy
Urticaria, Acute

Diagnosis
Key Points
Initial diagnosis based on appearance of the affected area
Skin biopsy will be performed to confirm diagnosis and to rule out other conditions

Pemphigoid gestation is is typically diagnosed based on the characteristic appearance of the affected area. A skin biopsy will be performed to confirm the diagnosis and to rule out similar appearing conditions.

Treatment
Primary goal of treatment is the relief of symptoms and prevention of secondary infection
Various treatments are available
In rare cases, complications may result from the condition

The primary goal in treating pemphigoid gestationis is the relief of symptoms and the prevention of secondary infection. Topical corticosteroids are typically used to treat moderate cases, while systemic corticosteroids may be required in more severe cases. In all cases, minimum effective doses should be utilized to prevent side effects. Oral antihistamines may be effective in relieving itching. In rare cases, complications such as premature delivery, temporary transient blisters affecting the infant, and secondary infection may occur as a result of the condition.