Herpes Simplex

 

These painful eczematous lesions at the angle of the mouth and the base of the nostrils had been present in a 52-year-old woman for 3 days (A).
Some of the vesicles had ulcerated and left a crust over the region. The patient said she had had similar attacks in the past. The diagnosis of recurrent herpes simplex virus 1 (HSV-1) infection was made. The patient was treated with acyclovir for 1 week, and all the lesions disappeared.

The painful vesicles of HSV-1 infection appear most commonly on the lip and rarely on other regions of the face, as in this patient. It is frequently difficult to distinguish primary HSV infection from a recurrent attack, because the presentation can be similar. Unless the history suggests otherwise, assume that an HSV infection is primary and treat the patient accordingly. In a second atypical case, numerous small pustules with surrounding erythema were seen on the thumb of a 5-year-old girl, a thumb-sucker (B).

She also had recurrent tiny ulcerations on one side of her tongue. The thumb lesions had developed 2 days earlier as clear vesicles and became pustular overnight. She now had a low-grade fever and decreased appetite. One lesion was deroofed with a fine scalpel and the fluid was cultured. The culture grew HSV-1. After treatment with mupirocin ointment, 3 times daily, the thumb lesions resolved rapidly.

(Case and photograph A courtesy of Sonia Arunabh, MD, and Naveen Verma, MD; case and photograph B courtesy of Robert P. Blereau, MD.)