Klippel-Trenaunay Syndrome

Klippel-Trenaunay syndrome is a rare congenital vascular disorder characterized by a triad of abnormalities:

1. Port-wine stain (cutaneous capillary malformation)
2. Varicose veins
3. Hypertrophy of bones and soft tissues (e.g., limb length discrepancy or limb overgrowth)

Pathophysiology

• It is often caused by a somatic mutation in genes involved in vascular development, specifically affecting the PIK3CA gene.
• Abnormal development and function of capillaries, veins, and lymphatics lead to these clinical manifestations.
• KTS is usually sporadic but can sometimes be inherited in an autosomal dominant pattern.