Eczema herpeticum and clinical criteria for investigating smallpox

Abstract

Eczema herpeticum can clinically resemble smallpox. On the basis of the algorithm for rapid evaluation of patients with an acute generalized vesiculopustular rash illness, our patient met criteria for high risk for smallpox. The Tzanck preparation was critical for rapid diagnosis of herpetic infection and exclusion of smallpox.

Figure 1

Clinical photographs of the patient. A) Patient with generalized pustules, which were deep seated, monomorphic, dome shaped, and firm and were distributed densely on forearms and abdomen. B) Umbilicated papulopustules. C) Umbilicated papulopustules in the same stage of evolution; no herpetiform clusters or red areolae are seen around the lesions.

Figure 2

Photomicrographs of the patient’s eczema herpeticum. A) Epithelial necrosis with cellular ballooning and multinucleated giant cells. B) Ballooning degeneration of keratinocytes. C) Positive immunohistochemical stain for herpes simplex virus.