Sindrome da delezione del cromosoma 18p. Su di un caso in associazione con alopecia universale e angioma piano

18p syndrome, or 18p monosomy, is a structural chromosomal anomaly caused by the absence of the short branch of chromosome 18. It frequently manifests in the form of mental retardation (98%), short stature (80%) IgA deficit (50%), lid drop (23%), strabismus (20%) and, only rarely, dermatological disorders. Described for the 1^st time by Grouchy et al. in 1963, 18p monosomy is still relatively unknown because of its extreme rarity. Of more than 100 cases presented in the literature, only 1 case observed the association of this syndrome with a form of congenital alopecia. We report the case of a girl affected by 18p monosomy who reached our observation in February 2002. Study of the karyotype enabled diagnosis of the syndrome due to deletion of the short branch of chromosome 18p, with treat-point in band 112. Alongside the commoner signs of the disorder such as IgA deficit, macroglossia, clinodactylism, lid drop, strabismus and slight mental retardation, the young patient also had dermatological manifestations in the form of a flat angioma or her left cheek, and acquired universal alopecia, for the 1^st time observed in association with 18p syndrome.