Melanocyte stimulation in focal dermal hypoplasia with unusual pigmented skin lesions: a histologic and immunohistochemical study.

Focal dermal hypoplasia (FDH) or Goltz syndrome is a rare genodermatosis transmitted in a dominant, X-linked mode. It is characterized clinically by atrophic skin lesions, multiple mucocutaneous papillomas, hyperpigmented linear skin lesions, and several skeletal and visceral anomalies. We followed over several years a female patient with FDH, who had the characteristic atrophic cutaneous lesions and periorificial papillomas, who developed at the periphery of atrophic lesions peculiar lentigo-like pigmented macules.

Phacomatosis pigmentokeratotica (Happle) in a 23-year-old man.

Phacomatosis pigmentokeratotica is a rare but highly characteristic disease defined by the occurrence of an organoid naevus with sebaceous differentiation, a speckled-lentiginous naevus and other associated anomalies. It is probably caused by the twin-spot phenomenon. We report on a 23-year-old male electrician with 10 irregularly shaped, sharply demarcated, brownish-yellow papillomatous plaques following Blaschko's lines, as well as 6 large, sharply demarcated, round to oval, slightly greyish macules with pewit-egg-like dots, involving both buttocks, the right thigh, the right knee, the right pectoral region and the upper back.