Blisters can be related to bug bites, contact allergy, friction, drug reaction, vasculitis, primary genetic disease of the skin, and fluid overload A full discussion of blisters can be found in Chapter 67 Rash: Vesiculobullous Chapter 70 Rash: Papulosquamous Eruptions and Viral Exanthems , covers HSV and Chapter 65 Rash: Atopic/Contact Dermatitis and Photosensitivity , covers eczema herpeticum Localized Eruptions Without Fever Contact dermatitis, insect bites, papular acrodermatitis, and scabies usually present in a localized distribution; however, all may appear as a more generalized eruption in extensive cases Contact Dermatitis Contact dermatitis may be caused either by a primary exposure to an irritant or by an acquired delayed hypersensitivity response to a sensitizing substance A sharp demarcation commonly exists between the involved and uninvolved skin areas Affected skin is erythematous with variable numbers and combinations of macules, papules, vesicles, and/or bullae Diagnosis depends on obtaining a thorough history of exposure and the presence of a characteristic localized pattern of rash Treatment for both types of these dermatitides includes eliminating exposure to offending irritants, providing topical or systemic antipruritic agents, and for more severe cases, providing topical or systemic steroids Please see Chapter 65 Rash: Atopic/Contact Dermatitis and Photosensitivity for additional information Insect Bites Virtually all children experience insect bites Mosquitoes, fleas, and bedbugs are the most common offenders Diagnosis depends on the season, the climate, exposure to animals, and distribution and appearance of the lesions Care is aimed at minimizing discomfort with topical or systemic antihistamines and/or topical steroids Papular Acrodermatitis (Gianotti–Crosti Syndrome) Papular acrodermatitis is an eruption of unclear cause that has been associated with hepatitis B, EBV, and other viral infections in young children, including a similar reaction in the setting of MC In the pediatric population, 85% are younger than years The eruption may follow a low-grade fever or mild upper respiratory symptoms