Herpes Zoster Involving the S1 Dermatome

A 19-month-old female infant presented with a 1-week history of ascending linear erythematous eruptions on the left calf. She showed no indications of immune disturbances and was a full-term infant with a healthy rate of weight gain and development. She had been immunized with the varicella vaccine 7 months before presentation. Physical examination revealed a vesicular rash in the S1 dermatome of the left leg (Panel A). A scraping from the base of several vesicles was obtained, and a direct immunofluorescence antigen assay was performed; the results were positive for the varicella–zoster virus (read more)