A Case Of Pemphigoid Gestationis

A 37-year-old pregnant woman presented to the hospital with severe preeclampsia. After all medical methods were tried and failed to control her severe preeclampsia, a joint decision was made to induce
labor to save the life of the mother. The pregnancy was too early for the fetus to survive.
The following day she began to develop the lesions shown in picture above. Her past history includes antiphospholipid syndrome with multiple pregnancy losses. This was her third episode of having such skin lesions.
A diagnosis of pemphigoid gestationis was made after biopsy results from the lesions.

Case Discussion
 Pemphigoid Gestationis

Pemphigoid gestationis is a rare autoimmune bullous dermatosis of pregnancy. The disease was originally known as herpes gestationis because of it visual similarities to herpes simplex infection. However, that term has fallen out of favor because pemphigoid gestationis is not associated with active or prior herpes virus infection.

Pemphigoid gestationis, is defined as a bullous or blistering disease that is associated with pregnancy or with trophoblastic tumors

Pathology: 

• The pathophysiology of the disease involves immunoglobulin (Ig) G antibodies that attack cells in the skin.

• The IgG attacks the same antigen (bullous pemphigoid antigen) as in bullous pemphigoid. This antigen is a transmembrane protein that is part of the hemidesmosome, which connects the basal cells
of the epidermis to the basement membrane.
• When the inflammatory response is activated, the hemidesmosomes are destroyed and the epidermis separates from the dermis.
• It is unknown why some patients form these antibodies.
• Rarely, pemphigoid gestationis persists for years postpartum.
• There is no scarring from the lesions.

Clinical features; 
Pemphigoid gestationis typically erupts during the second or third trimester and, rarely, postpartum and first trimester. Symptoms may abate at the end of pregnancy; however, flares can occur immediately after delivery.
• Pruritus sometimes precedes the rash and vesicles may develop early.
• The initial manifestations are erythematous urticarial patches and plaques, which typically start around the umbilicus. The lesions progress to tense vesicles.
•The rash begins on the trunk around the umbilicus as pruritic papules or plaque and may progress to bullae. Lesions may occasionally be seen on the palms and soles, and rarely on the face or mucous membranes.

Diagnosis :
Skin biopsy including the edge of a blistering lesion reveals a subepidermal vesicle with a perivascular lymphocytic and eosinophilic infiltrate.
• Eosinophils may appear at the dermoepidermal junction and inside the vesicle; the degree of eosinophilia correlates with disease severity.
• Basal cell necrosis and papillae edema are usually present.

A skin biopsy of perilesional skin for indirect immunofluorescent staining shows complement 3 in a homogeneous linear band at the basement membrane. This is pathognomonic for pemphigoid gestationis.

Management:
1. Tepid baths, compresses, and emollients may help alleviate pruritus.
2. Topical steroids and oral antihistamines should be administered in early or mild cases, but are usually ineffective in more severe cases.
3. Systemic steroids, such as prednisone (0.5 mg/kg per day), are effective to control most cases.The dose may be tapered and eventually discontinued in many pregnancies.

Prognosis: Pemphigoid gestationis typically regresses spontaneously without scarring within weeks to months after delivery. It may recur in subsequent pregnancies or may be precipitated by the use of oral contraceptives.