Photo Quiz: Wart or Mimic?

Case 1:

Can you identify this asymptomatic lesion on the neck of a healthy 14-year-old boy?

Case 1: This is an epidermal nevus. Unlike warts, epidermal nevi are usually soft. Typically, they are grouped or linear and do not have the potential for malignant degeneration. An epidermal nevus may be mistaken for a nevus sebaceus of Jadassohn (organoid nevus), which is often linear and occasionally becomes malignant. These nevi are red or orange in white persons and brown in black persons.

Case 2:

These rough, irregular papules arose under the nail of a healthy 16-year-old boy.

What does this look like to you?

Case 2: This is a subungual/periungual wart, a keratotic papule that resists treatment. Subungual warts underlie and infiltrate the nail fold; periungual warts abut the nail fold. Subungual warts are more difficult to eradicate than other types of warts because a nidus of infected tissue remains after chemical or surgical treatment, which allows for reextension of the lesion.

Case 3:

This lesion has bothered a healthy teenaged boy.

Can you identify it?

Case 3: This is a common wart. It is keratotic and displays the characteristic interrupted skin lines (dermatoglyphs).