REPORT OF A CASE
A 17-year-old white boy was referred to us from the neurology clinic for evaluation of congenital skin lesions of the right hand and the right foot. The patient was undergoing follow-up by the neurology clinic for a seizure disorder and left hemiparesis. The patient also had scoliosis.The dermatologic examination revealed a linear arrangement of multiple 1- to 3-mm firm papules with a central keratotic plug located along the lateral portions of the right palm and the right foot. The lesions were also scattered along the thenar eminence of the right palm. All lesions were asymptomatic and could not be dislodged with a comedone extractor.Figures 1 and 2 are clinical photographs of the patient's right hand and foot, respectively. Figures 3 and 4 are photomicrographs of a 4-mm punch biopsy specimen taken from a lesion on the patient's right palm.What is your diagnosis?
Porokeratotic eccrine ostial and dermal duct nevus.
Histopathologic examination revealed multiple depressions and comedolike invaginations of the epidermis filled with parakeratotic columns.
Solis J, Sau P, James WD. Puzzling Palmar and Plantar Papules. Arch Dermatol. 1991;127(8):1223-1224. doi:10.1001/archderm.1991.01680070123021