Porokeratotic eccrine ostial and dermal duct nevus

We report 2 cases of congenital porokeratotic eccrine nevus in a 5-year-old girl and a 7-year-old boy. The clinical manifestations were those of nevus comedonicus palmaris. The histologic picture consisted of comedo-like dilatations and cornoid lamellae involving the eccrine ostia and ducts. One of the cases showed anomalies in the dermal eccrine ducts. We believe that these lesions are eccrine hamartomas unrelated to porokeratosis. We review similar cases from the literature and discuss the differential diagnosis.