Juvenile xanthogranuloma in a congenital melanocytic nevus

A 6-year-old boy was evaluated for a 6-month history of a 2x1mm yellowish papule that developed within a congenital melanocytic nevus (CMN) located on his back. Dermoscopic examination showed a homogeneous yellowish background with localized pigmented struc tures. In vivo reflectance confocal microscopy revealed an area with sharp borders, characterized by thinning of the epidermis and the absence of rete ridges. At the dermo- epidermal junction, the dermal papillae did not exhibit the typical ringed pattern.