Synonym: naevus varicosus osteohypertrophicus
The syndrome usually involves one of the lower extremities but it may involve both.
Classic triad:
(1) naevus flammeus (port wine stain)
(2) hemihypertrophy of bone and soft tissue, resulting in enlargement and lengthening of the affected limb and causing lower limb inequality
(3) angiodysplasia of the venous system in the affected limb, typically resulting in varicose veins, venous thrombosis and/or chronic venous ulcers. The venous system may show venous agenesis or hypoplasia, valvular incompetence, embryonic veins or other defects.
The syndrome can be identified during infancy or early childhood but it may not be recognized until later.
Additional findings may include:
(1) defects in digits (polydactyly, syndactyly, oligodactyly)
(2) macrocephaly
(3) epidermal nevus
The presence of a large, clinically apparaent arteriovenous malformation suggests Parkes-Weber Syndrome (see next section).
