Two healthy infants present with eczematous plaques on the posterior neck. Their parents report that the lesions had developed over birthmarks, each of which their PCPs had previously documented as a nevus simplex.
is a spontaneous halo-like eczematous reaction that occurs at a preexisting skin lesion, and has been found to occur in many types of lesions including nevus simplex (aka macular stain, angel’s kiss, stork bite, or salmon patch), nevus flammeus (aka port wine stain), capillary malformations, seborrheic keratosis, dermatofibroma, molluscum contagiosum, melanoma, etc. The cause is unknown. Prognosis is good, and typically improves with topical corticosteroids, although some lesions may resolve spontaneously without treatment while others may recur after treatment discontinuation.