Plaques of Pregnancy his relatively common pregnancy-speciic dermatosis is characterized by its benign efects on pregnancy and by intensely pruritic 1-to 2-mm erythematous papules that coalesce to form urticarial plaques. Also known as poymorphic eruption of pregnancy, PUPPP usually appears late in pregnancy (Rudolph, 2005). Rarely, postpartum onset has been described (Park, 2013). he rash afects the abdomen and proximal thighs in 97 percent of women (Fig. 62-2). Lesions often initially form within striae but show periumbilical sparing. The face, palms, and soles also are rarely involved (High, 2005). It is more frequent in white and nulliparous women, those with multifetal gestation, and those carrying a male fetus (Regnier, 2008). PUPPP seldom recurs in subsequent pregnancies (Ahmadi, 2005). Its cause is unknown, but an autoimmune basis is not implicated (Lawley, 1979).
PUPPP may be compared with several skin eruptions. Some include contact dermatitis, drug eruption, viral exanthem, insect bites, scabies infestation, pityriasis rosea, and the other pregnancy-speciic dermatoses. It also may appear similar to early PC that has not yet blistered. In unclear cases, skin biopsy and negative serum collagen V1I antibody levels help to differentiate the two. Pruritus will usually respond to treatment with oral antihistamines, skin emollients, and topical corticosteroids. A few women will need systemic corticosteroids to relieve severe itching (Scheinfeld, 2008).
FIGURE 62-2 Pruritic urticarial papules and plaques of pregnancy (PUPPP) shows sma" papules on the buttock and proximal thigh and within abdominal striae.
PUPPP usually resolves within several days following delivery and leaves no scarring. In 15 to 20 percent of women, however, symptoms persist for 2 to 4 weeks postpartum (Vaughan Jones, 1999).
• Atopic Eruption of Pregnancy his umbrella term encompasses three conditions previously considered separate: eczema in pregnancy, prurigo of pregnancy, and pruritic folliculitis of pregnancy (Ambros-Rudolph, 2006). Two thirds of women with atopic eruption have widespread eczematous changes, whereas the other third have papular lesions (American Academy of Dermatology, 201r1). As a group, these pose no risk to the fetus. Diagnosis is greatly aided by a history of atopy and by rash characteristics.
Eczema in pregnany has the appearance of traditional eczema but with a pregnancy onset. It is the most common pregnancy-specific dermatosis, and afected skin shows dry, thickened, scaly, red patches involving extremity lexures, nipples, neck, and face. In contrast, prurigo of pregnancy, also known as prurigo gestationis) is characterized by 5-to 10-mm, itchy, erythematous papules or nodules commonly found on the extensor surfaces and trunk. Last, pruritic olliculitis of pregnancy is rare and notable for small, erythematous follicular papules and sterile pustules predominantly on the trunk. Onset for all is during the second or third trimester, although eczema in pregnancy may develop earlier than the other two. All lesions commonly resolve with delivery, but may persist for up to 3 months postpartum. Recurrence with subsequent pregnancies is variable but common.