Focal dermal hypoplasia: report of a case with cutaneous and skeletal manifestations

Focal dermal hypoplasia is a rare genodermatosis characterized by developme ntal defects of the skin, resulting in widespread linear lesions of dermal hypoplasia with adipose tissue in the dermis. We describe a 13-year-old gir l who has typical cutaneous lesions which have been present since birth; sh e also has some of the associated dental, nail and skeletal abnormalities, while an X-ray of the long bones osteopathia striata is visible, a feature seen in a high proportion of cases of focal dermal hypoplasia. Eighty-eight per cent of the case reports in the literature are of females and X-linked dominance is the likely mode of inheritance. It has also been proposed tha t the condition is lethal in homozygous males and the high frequency of mis carriages on the maternal side of this patient's family is consistent with that lethality in males. The literature, particularly with regard to pathog enesis and inheritance, is discussed.