Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
Age of Onset
Autosomal dominant ?A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease
Autosomal recessive ?Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype
X-linked dominant ?X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.
X-linked recessive ?Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder
Mitochondrial or multigenic ?Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.
Multigenic or multifactor ?Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.
Other Names (AKA)
Klippel Trenaunay syndrome; Klippel-Trenaunay-Weber syndrome; KTW syndrome;
Blood Diseases; Congenital and Genetic Diseases; Musculoskeletal Diseases;
Most, if not all, cases of KTS are caused by
This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
Clouding of the lens of the eye
[ more ]
Collection of dilated blood vessels that forms mass
Hand has less than 5 fingers
|Hemihypertrophy of upper limb||
Overgrowth of one arm
Increased size of skull
Large head circumference
[ more ]
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference
[ more ]
Open skin sore
Poorly functioning veins
|30%-79% of people have these symptoms|
|Abnormality of coagulation||0001928|
Abnormality of cognition
[ more ]
Multiple fatty lumps
|Tricuspid valve prolapse||0001704|
|5%-29% of people have these symptoms|
|Abnormality of the menstrual cycle||0000140|
Bacterial infection of skin
[ more ]
|Congestive heart failure||
[ more ]
Asymmetry of face
[ more ]
Blood in urine
|Hemihypertrophy of lower limb||
Overgrowth of one leg
Swelling caused by excess lymph fluid under skin
|Peripheral arteriovenous fistula||0100784|
Blood clot in artery of lung
Increased body height
|Telangiectasia of the skin||0100585|
Blood clot in vein
|Percent of people who have these symptoms is not available through HPO|
|Abnormality of blood and blood-forming
|Hyperpigmented nevi and streak||0005606|
Mental retardation, nonspecific
[ more ]
No previous family history
Webbed fingers or toes
Some researchers believe all KTS is caused by somatic mutations in the PIK3CA gene and when a mutation cannot be found, the person may actually have a different disorder. Other researchers believe KTS can be caused by mutations in other yet to be discovered genes.
Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.
Conditions with similar signs and symptoms from Orphanet
The differential diagnosis should include venous dysplasias, lymphedema and bone tumors.
Visit the Orphanet disease page for more information.
Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.
Klippel-Trenaunay Support Group (K-T Support Group)
1471 Greystone Lane
Milford, OH 45150
Contact form: https://k-t.org/about-us/contact
National Organization of Vascular Anomalies (NOVA)
PO Box 38216
Greensboro, NC 27438-8216
These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.
- MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
- Genetics Home Reference (GHR) contains information on Klippel-Trenaunay syndrome. This website is maintained by the National Library of Medicine.
- The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
- The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
- Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
- The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
- Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
- Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Klippel-Trenaunay syndrome. Click on the link to view a sample search on this topic.
- Klippel-Tranaunay Syndrome. Genetics Home Reference. 2016; https://www.ghr.nlm.nih.gov/condition/klippel-trenaunay-syndrome.
- Luks VL, Kamitaki N, Vivero MP, Uller W, Rab R, Bovée JV, Rialon KL, Guevara CJ, Alomari AI, Greene AK, Fishman SJ, Kozakewich HP, Maclellan RA, Mulliken JB, Rahbar R, Spencer SA, Trenor CC 3rd, Upton J, Zurakowski D, Perkins JA, Kirsh A, Bennett JT, Dobyns WB, Kurek KC, Warman ML, McCarroll SA, and Murillo R. Lymphatic and other vascular malformative/overgrowth disorders are caused by somatic mutations in PIK3CA. Journal of Pediatrics. April 2015; 166(4):1048-54. https://www.ncbi.nlm.nih.gov/pubmed/25681199.
- Vahidnezhad H, Youssefian L, and Uitto J. Klippel-Trenaunay syndrome belongs to the PIK3CA-related overgrowth spectrum (PROS). Experimental Dermatology. Januaray 2016; 25(1):17-19. https://www.ncbi.nlm.nih.gov/pubmed/26268729.
- Mirzaa G, Conway R,Graham JM, and Dobyns WB.. PIK3CA-Related Segmental Overgrowth. GeneReviews. August 15 2013; https://www.ncbi.nlm.nih.gov/books/NBK153722/.
- NINDS Klippel-Trenaunay Syndrome (KTS) Information Page. National Institute of Neurological Disorders and Stroke (NINDS). September 30 2011; https://www.ninds.nih.gov/Disorders/All-Disorders/Klippel-Trenaunay-Syndrome-KTS-Information-Page.
- About K-T: Management and Treatments. Klippel Trenaunay (KT) Support Group. https://k-t.org/about-kt/management-and-treatments. Accessed 11/11/2014.