Single efflorescences of both speckled lentiginous nevus (SLN) and segmental unilateral lentiginosis (SUL) look similar and may be easily confused. Herein, we detail a case of a segmental SLN to draw attention to the distinction.
A well-developed 12-year-old boy developed SLN between age 5 and 6 months, which began on the dorsal surface of his left hand and expanded slowly centripetally to his chest and back on the left side during the course of years, strictly following the lines of Blaschko. His mother could not remember any signs of the condition at birth, but nor could she exclude the possibility that a light tan macule might have been present at birth.
Barysch MJ, Dummer R. The Spectrum of Widespread Hyperpigmentations From SLN to SUL. Arch Dermatol. 2009;145(8):953–954. doi:10.1001/archdermatol.2009.163