Chapter 60 Dermatoses of pregnancy
Specific dermatoses of pregnancy
2. What is pruritic urticarial papules and plaques of pregnancy?
Pruritic urticarial papules and plaques of pregnancy (also known as polymorphic eruption of pregnancy, or PUPPP) has an incidence of 1/200 pregnancies. The onset of PUPPP is usually in the third trimester. The pruritic, erythematous, papules and plaques are usually first seen in the abdominal striae (stretch marks) and then spread to the chest, trunk, and extremities. The papules and plaques typically spare the palms, soles, face, and mucous membranes. Large vesicles or bullae are uncommon, though pinpoint vesicles may be seen (Fig. 60-1).
4. How is PUPPP treated?
6. What is pemphigoid gestationis?
Pemphigoid gestationis (also called herpes gestationis or gestational pemphigoid) is an autoimmune subepidermal bullous disorder of pregnancy that may start in the 2nd trimester, the 3rd trimester, or in the postpartum period. The skin lesions are characterized by urticarial papules and plaques, which then progress into painful bullae. The lesions of pemphigoid gestationis initially present periumbilically (Fig. 60-2A), and then spread to involve the trunk and extremities (Fig. 60-2B), usually sparing the face.
7. What are the antigens associated with the development on pemphigoid gestationis?
Bullous pemphigoid antigen 2 (BPAG2) is a 180 kDal transcellular glycoprotein that is part of the hemidesmosome (a structure that binds epithelial cells to the basement membrane of the epidermis). IgG binds to BPAG2 and triggers the classic complement pathway leading to a deposition of C3 along the basement membrane zone (Fig. 60-3). Deposition of complement along the basement membrane zone leads to a recruitment of inflammatory cells, particularly eosinophils. This cascade ultimately leads to a release of proteolytic enzymes that cleave portions of the epidermis from the dermis.
Key Points: Pemphigoid Gestationis
1. Pemphigoid gestationis is an autoimmune disease that occurs during pregnancy, and it is characterized by IgG1 antibodies directed at bullous pemphigoid antigen–1 in the basement membrane zone.
2. Direct immunofluorescent study demonstrates linear C3 and/or IgG along the basement membrane zone and is the diagnostic test of choice to establish the diagnosis.
4. The umbilical area is preferentially affected in pemphigoid gestationis and can be a clue to the diagnosis.
8. Which histocompatibility leukocyte antigen (HLA) types have been associated with pemphigoid gestationis?
9. Compare PUPPP and pemphigoid gestationis.
See Table 60-1.
PUPPP | PEMPHIGOID GESTATIONIS | |
---|---|---|
Clinical presentation | Pruritic erythematous papules and plaques Initial lesions present in the abdominal striae, spreading to the trunk and extremities; vesicles may be present Usually spares the palms and soles | Urticarial papules, plaques, and blisters Initial lesions start periumbilically and spread to the trunk and extremities The palms and soles are commonly involved |
Direct immunofluorescence |