A 10-year-old girl complained of slight fatigue and malaise. A 6-mm tense blister had developed on the dorsum of her right foot (A), lesions had arisen on the palms, and a pinpoint, whitish ulcer had erupted anterior to the frenular attachment (B). A friend of the patient had similar symptoms and lesions, and vesicles on the buttocks as well.
The lesions were not multiloculated, and Tzanck stain results were negative, which made the diagnosis of herpes simplex virus infection less likely. Hand-foot-and-mouth disease was diagnosed. Most commonly caused by coxsackievirus A16, this disease can be attributed to other enteroviruses as well. The usually benign vesicular exanthem spreads easily and generally affects children younger than 10 years. Hand-foot-and-mouth disease caused by enterovirus is generally more severe than that attributable to coxsackie A16, and may be complicated by aseptic meningitis, encephalitis, or paralysis.1
Hand-foot-and-mouth disease is most often characterized by 2- to 6-mm, round-to-oval vesicles and bullae on the dorsa of the feet and hands. These follow the appearance of smaller oral lesions, which quickly lose their roof. Lesions also may arise on the buttocks; thus, the presence of vesicles in atypical locations does not preclude the diagnosis.
If necessary, symptomatic treatment can be offered. The lesions and symptoms usually resolve within 2 weeks, and immunity is thus acquired.