Partial unilateral lentiginosis with ipsilateral Lisch nodules and axillary freckling

A 9-year-old Taiwanese girl had an unusual combination of multiple lentigines clustered on her left face, 3 cafe-au-lait spots on her left arm and ipsilateral axillary freckling. Two Lisch nodules of the iris were recognized in the left eye but none in the right eye, which is why we established a diagnosis of segmental neurofibromatosis 1. No family member had any sign of neurofibromatosis 1. Moreover, the patient had a large speckled lentiginous nevus involving the left side of her trunk, and her father showed a similar skin disorder on his left buttock. These lesions were taken to be unrelated to the patient's segmental neurofibromatosis 1. This case provides further evidence in favor of the concept that partial unilateral lentiginosis represents a mosaic manifestation of type 1 neurofibromatosis.