Focal dermal hypoplasia, caused by mutations in PORCN, is an X-linked ectodermal dysplasia, also known as Goltz syndrome. Only seven cases of unilateral or almost unilateral focal dermal hypoplasia have been reported in the English literature and there have been no previously reported cases in the Republic of Korea. A 19-year-old female presented with scalp defects, skin lesions on the right leg and the right trunk, and syndactyly of the right fourth and fifth toes. Cutaneous examination revealed multiple atrophic plaques and a brown and yellow mass with fat herniation and telangiectasia that was mostly located on the lower right leg. She had syndactyly on the right foot and the scalp lesion appeared to be an atrophic, membranous, fibrotic alopecic scar. A biopsy of the calf revealed upper dermal extension of fat cells, dermal atrophy, and loss of dermal collagen. A diagnosis of almost unilateral focal dermal hypoplasia was made on the basis of physical and histologic findings. Henceforth, the patient was referred to a plastic surgeon and an orthopedics department to repair her syndactyly.
Keywords: Ectodermal dysplasia; Focal dermal hypoplasia; Syndactyly.