Klippel-Trenaunay-Weber Syndrome (KTS)

External Ids:

MedlinePlus Genetics: ⁴² Klippel-Trenaunay syndrome is a condition that affects the development of blood vessels, soft tissues (such as skin and muscles), and bones. The disorder has three characteristic features: a red birthmark called a port-wine stain, abnormal overgrowth of soft tissues and bones, and vein malformations.Most people with Klippel-Trenaunay syndrome are born with a port-wine stain. This type of birthmark is caused by swelling of small blood vessels near the surface of the skin. Port-wine stains are typically flat and can vary from pale pink to deep maroon in color. In people with Klippel-Trenaunay syndrome, the port-wine stain usually covers part of one limb. The affected area may become lighter or darker with age. Occasionally, port-wine stains develop small red blisters that break open and bleed easily.Klippel-Trenaunay syndrome is also associated with overgrowth of bones and soft tissues beginning in infancy. Usually this abnormal growth is limited to one limb, most often one leg. However, overgrowth can also affect the arms or, rarely, the torso. The abnormal growth can cause pain, a feeling of heaviness, and reduced movement in the affected area. If the overgrowth causes one leg to be longer than the other, it can also lead to problems with walking.Malformations of veins are the third major feature of Klippel-Trenaunay syndrome. These abnormalities include varicose veins, which are swollen and twisted veins near the surface of the skin that often cause pain. Varicose veins usually occur on the sides of the upper legs and calves. Veins deep in the limbs can also be abnormal in people with Klippel-Trenaunay syndrome. Malformations of deep veins increase the risk of a type of blood clot called a deep vein thrombosis (DVT). If a DVT travels through the bloodstream and lodges in the lungs, it can cause a life-threatening blood clot known as a pulmonary embolism (PE).Other complications of Klippel-Trenaunay syndrome can include a type of skin infection called cellulitis, swelling caused by a buildup of fluid (lymphedema), and internal bleeding from abnormal blood vessels. Less commonly, this condition is also associated with fusion of certain fingers or toes (syndactyly) or the presence of extra digits (polydactyly).

MalaCards based summary: Klippel-Trenaunay-Weber Syndrome, also known as klippel-trenaunay syndrome, is related to angioosteohypertrophic syndrome and weber syndrome. An important gene associated with Klippel-Trenaunay-Weber Syndrome is PIK3CA (Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha), and among its related pathways/superpathways are Signal Transduction and G-protein signaling RAC1 in cellular process. The drugs Miconazole and Sirolimus have been mentioned in the context of this disorder. Affiliated tissues include skin, bone and eye, and related phenotypes are hemangioma and venous insufficiency

NINDS: ⁵² Klippel-Trenaunay syndrome (KTS) is a rare congenital malformation involving blood and lymph vessels and abnormal growth of soft and bone tissue.  Typical symptoms include hemangiomas (abnormal benign growths on the skin consisting of masses of blood vessels) and varicose veins.  Fused toes or fingers, or extra toes or fingers, may be present.  In some cases, internal bleeding may occur as a result of blood vessel malformations involving organs such as the stomach, rectum, vagina, liver, spleen, bladder, kidneys, lungs, or heart.  Individuals are also at risk for blood clots. The cause of the disorder is unknown. A similar port-wine stain disorder in which individuals have vascular anomalies on the face as well as in the brain is Sturge-Weber syndrome. These individuals may experience seizures and mental deficiency.  In some cases, features of the Klippel-Trenaunay syndrome and Sturge-Weber syndrome coincide.  Another overlapping condition is the Parkes-Weber syndrome, which is characterized by abnormal connectivity between the arterial and venous system (arteriovenous fistulas).

GARD: ¹⁹ Klippel-Trenaunay syndrome (KTS) is a syndrome that affects the development of blood vessels, soft tissues, and bones. This syndrome has three characteristic features: a red birthmark called a port-wine stain, overgrowth of soft tissues and bones, and vein malformations such as varicose veins or malformations of deep veins in the limbs. The overgrowth of bones and soft tissues usually begins in infancy and is most often only affects one leg. However, it can also affect the arms or sometimes the upper body area (torso). The overgrowth can cause pain, a feeling of heaviness, and make the affected leg (or arm) hard to move. Most, if not all, cases of KTS are caused by somatic genetic changes in the PIK3CA gene.

UniProtKB/Swiss-Prot: ⁷³ Congenital disease characterized by malformations of capillary (98% of KTS patients), venous (72%) and lymphatic (11%) vessels, and bony and soft tissue hypertrophy that leads to large cutaneous hemangiomata with hypertrophy of the related bones and soft tissues.

Disease Ontology: ¹¹ A syndrome that is characterized by large cutaneous hemangiomata with hypertrophy of the related bones and soft tissues.

Wikipedia: ⁷⁵ Klippel-Trénaunay syndrome, formerly Klippel-Trénaunay-Weber syndrome and sometimes... more...

Clinical features from OMIM®:

Search NIH Clinical Center for Klippel-Trenaunay-Weber Syndrome