Klippel-Trenaunay Syndrome

Klippel-Trenaunay Syndrome (KTS) is a rare congenital medical condition characterized by a triad of capillary malformation, venous malformation, and limb hypertrophy. This syndrome was first described by French physicians Maurice Klippel and Paul Trenaunay in 1900, and it is sometimes referred to as Klippel-Trenaunay-Weber syndrome, although this term is less preferred due to the distinct nature of Parkes Weber syndrome, which involves arteriovenous malformations.

Symptoms and Signs

The hallmark features of Klippel-Trenaunay Syndrome include:

• Port-wine stains (capillary malformations) that typically appear as flat, pink to red to purple lesions present at birth and grow proportionately with the child.
• Venous malformations including varicose veins, deep venous anomalies, and, in some cases, venous ulcers.
• Limb hypertrophy where one or more limbs are larger than the others due to soft tissue and bone overgrowth. This can lead to significant functional impairment and cosmetic concerns.

Additional symptoms may include:

• Lymphatic abnormalities leading to lymphedema.
• Increased risk of deep vein thrombosis (DVT) and pulmonary embolism.
• Localized intravascular coagulopathy, a condition where the blood within the malformed veins clots more easily.

Causes

The exact cause of Klippel-Trenaunay Syndrome is not fully understood, but it is believed to result from somatic mutations in the PIK3CA gene. These mutations are not inherited but occur after conception in one of the developing embryo's cells. The syndrome is considered sporadic, with no known risk factors for these mutations.

Diagnosis

Diagnosis of Klippel-Trenaunay Syndrome is primarily clinical, based on the characteristic triad of symptoms. Imaging studies such as ultrasound, MRI (Magnetic Resonance Imaging), and CT scan (Computed Tomography) can help assess the extent of the vascular malformations and hypertrophy. Genetic testing may also be conducted to identify PIK3CA mutations, although this is not routinely done.

Treatment

There is no cure for Klippel-Trenaunay Syndrome, and treatment is symptomatic and tailored to the individual's needs. Management strategies may include:

• Compression therapy to manage lymphedema and venous insufficiency.
• Laser therapy for port-wine stains.
• Sclerotherapy or surgical removal of problematic venous malformations.
• Orthopedic interventions to address limb length discrepancies and functional impairments.
• Anticoagulation therapy to prevent thromboembolic complications.

Prognosis

The prognosis for individuals with Klippel-Trenaunay Syndrome varies widely and depends on the severity of the symptoms and the extent of the vascular malformations. With appropriate management, most individuals can lead active, productive lives.

See Also

• Parkes Weber syndrome
• Sturge-Weber syndrome
• Capillary malformation-arteriovenous malformation syndrome