Contact dermatitis: Causes an acute eczematous rash results from a type IV hypersensitivity reaction to an allergen. In this case, the allergen was likely poison ivy resin because she presents with a characteristic rash. lesions are arranged perfectly linear, suggesting that the cause is external to the patient (i.e., a plant) Atopic dermatitis: Lesions are not characterized by linear distributions. In adolescents and adults, the most common sites of involvement are flexor surfaces, wrists/forearms and face. Erythema infectiosum, or fifth disease: "Slapped cheek" rash (edematous, erythematous plaques) in a febrile patient. Parvovirus B19 is the infectious agent. Centripetal rashes. Impetigo: Epidermal infection with staphylococci or streptococci that typically occurs on the face, neck, or extremities. Rash- vesicular with honey colored crusting and can be intensely pruritic.