This distribution of an inflammatory disorder in a very young child almost always indicates atopic dermatitis. The family history of asthma suggests the atopic diathesis.
A 9-month-old boy has had a pruritic facial rash that has resisted topical therapy. Another
9-month-old boy has had a similar rash, with no response to topical therapy. Both infants have the same condition and a family history of atopy.
Allergy testing can aid the diagnosis of allergic disorders; however, it is not diagnostic. With skin testing, in particular, a positive result does not necessarily indicate clinical allergy, and a negative result does not always exclude clinical relevance.
One week earlier, a 14-month-old girl with a history of eczema was evaluated because of a diffuse rash of excoriated lesions, some of them purulent. She was afebrile. Worsening eczema with secondary infection was diagnosed. Treatment with oral clindamycin was prescribed. At follow-up, the lesions had worsened. The child had multiple excoriated papules, some of which had coalesced into plaques. She also had two 5-mm vesicles on her right shoulder. Eczema herpeticum was diagnosed clinically. Culture of the vesicles later grew herpes simplex virus (HSV).