This 4-year-old boy with atopic dermatitis developed a pruritic
eruption typical of a primary cutaneous Herpes simplex
virus(HSV) infection. Eczema herpeticum, also known as Kaposi's
varicelliform eruption, represents widespread cutaneous HSV in
patients with pre-existing skin disorders. Atopic Dermatitis is
by far the most common underlying associated skin condition.
Other disorders that predispose patients to this primary HSV
infection include keratosis follicularis, pemphigus foliaceous
and icthyosis vulgaris. The differential diagnosis includes
widespread impetigo, scabies, papular urticaria, contact
dermatitis, and shingles. Many patients have a history of
exposure to a family member with recurrent HSV infection. A
Tzanck preparation is a useful bedside diagnostic technique, but
viral culture is confirmatory. Eczema herpeticum is treated with
oral antiviral medications, tap water and/or aluminum acetate
compresses 2 or 3 times a day, and oral antipruritics. Early and
aggressive therapy of secondary infec