Klippel-Trenaunay-type syndrome: an eponym for various expressions of the same entity.

Klippel-Trenaunay (KT) or as it is also called Klippel-Trenaunay-Weber (KTW) syndrome is a rare congenital phacomatosis of uncertain aetiology and variable expression. The classical syndrome is a triad of congenital mesodermal abnormalities characterized by cutaneous angiomatous nevus commonly called port-wine stain, venous varicosities and hypertrophy of soft tissue and/or overgrowth of bone of one or more limbs. Clinically, a diversity of phenotypes with subjacent malformations may be encountered all having in common abnormalities of the mesoblastic sheets that include angioblastic, lymphoblastic and osteoblastic lineages. Each of them may give rise to malformations that may exist alone or in an unlimited diversity of associations. We present three widely different clinical expressions of this syndrome and we support the proposal to group all these malformations under the eponym of Klippel-Trenaunay-Type (KTT) syndrome.