Andersen-Tawil syndrome

Title

Other Names:

Long QT syndrome 7; LQT7; Potassium-sensitive periodic paralysis, ventricular ectopy, and dysmorphic features; Long QT syndrome 7; LQT7; Potassium-sensitive periodic paralysis, ventricular ectopy, and dysmorphic features; Andersen cardiodysrhythmic periodic paralysis; Periodic paralysis, potassium-sensitive cardiodysrhythmic type See More

Categories:

Congenital and Genetic Diseases; Heart Diseases; Nervous System Diseases; Congenital and Genetic Diseases; Heart Diseases; Nervous System Diseases; RDCRN See More

Summary Summary

Andersen-Tawil syndrome is a type of long QT syndrome and is also considered a rare form of periodic paralysis. It causes episodes of muscle weakness, changes in heart rhythm (arrhythmia), and developmental abnormalities. Physical abnormalities associated with this condition typically affect the head, face, and limbs. About 60% of cases of Andersen-Tawil syndrome are caused by mutations in the KCNJ2 gene. The cause of the remaining cases remains unknown. This condition is inherited in an autosomal dominant pattern.^[1]^[2]

Last updated: 8/18/2015

Symptoms Symptoms

Anderson-Tawil syndrome causes episodes of muscle weakness (periodic paralysis), changes in heart rhythm (arrhythmia), and developmental abnormalities. The most common changes affecting the heart are ventricular arrhythmia, which is a disruption in the rhythm of the heart's lower chambers, and long QT syndrome. Long QT syndrome is a heart condition that causes the heart muscle to take longer than usual to recharge between beats. If untreated, the irregular heartbeats can lead to discomfort, fainting, or cardiac arrest.^[1]

Physical abnormalities associated with Andersen-Tawil syndrome typically affect the head, face, and limbs. These features often include a very small lower jaw (micrognathia), dental abnormalities, low-set ears, widely spaced eyes, and unusual curving of the fingers or toes (clinodactyly). Some affected people also have short stature and an abnormal curvature of the spine (scoliosis).^[1]

Last updated: 8/18/2015

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.

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Medical Terms	Other Names	Learn More: HPO ID
5%-29% of people have these symptoms
Specific learning disability		0001328
Percent of people who have these symptoms is not available through HPO
Antegonial notching of mandible		0003779
Autosomal dominant inheritance		0000006
Bidirectional ventricular ectopy		0005147
Blepharophimosis	Narrow opening between the eyelids	0000581
Brachydactyly	Short fingers or toes	0001156
Broad forehead	Increased width of the forehead Wide forehead [ more ]	0000337
Bulbous nose		0000414
Cleft palate	Cleft roof of mouth	0000175
Clinodactyly of the 5th finger	Permanent curving of the pinkie finger	0004209
Clinodactyly of the 5th toe		0001864
Delayed eruption of permanent teeth	Delayed eruption of adult teeth	0000696
Delayed skeletal maturation	Delayed bone maturation Delayed skeletal development [ more ]	0002750
Depressivity	Depression	0000716
Facial asymmetry	Asymmetry of face Crooked face Unsymmetrical face [ more ]	0000324
Growth abnormality	Abnormal growth Growth issue [ more ]	0001507
High palate	Elevated palate Increased palatal height [ more ]	0000218
Hypertelorism	Wide-set eyes Widely spaced eyes [ more ]	0000316
Hypokalemia	Low blood potassium levels	0002900
Hypoplasia of dental enamel	Underdeveloped teeth enamel	0006297
Hypoplasia of the maxilla	Decreased size of maxilla Decreased size of upper jaw Maxillary deficiency Maxillary retrusion Small maxilla Small upper jaw Small upper jaw bones Upper jaw deficiency Upper jaw retrusion [ more ]	0000327
Joint laxity	Joint instability Lax joints Loose-jointedness Loosejointedness [ more ]	0001388
Low-set ears	Low set ears Lowset ears [ more ]	0000369
Malar flattening	Zygomatic flattening	0000272
Microcephaly	Abnormally small skull Decreased circumference of cranium Decreased size of skull Reduced head circumference Small head circumference [ more ]	0000252
Oligodontia	Failure of development of more than six teeth	0000677
Palpitations	Missed heart beat Skipped heart beat [ more ]	0001962
Periodic hypokalemic paresis		0008153
Persistence of primary teeth	Delayed loss of baby teeth Failure to lose baby teeth Retained baby teeth [ more ]	0006335
Preauricular pit	Pit in front of the ear	0004467
Prolonged QT interval		0001657
Prominent frontal sinuses		0005478
Prominent U wave		0025072
Scapular winging	Winged shoulder blade	0003691
Scoliosis		0002650
Short foot	Short feet Small feet [ more ]	0001773
Short mandibular rami		0003778
Short metacarpal	Shortened long bone of hand	0010049
Short metatarsal	Short long bone of foot	0010743
Short palm		0004279
Short palpebral fissure	Short opening between the eyelids	0012745
Short phalanx of finger	Short finger bones	0009803
Slender long bone	Long bones slender Thin long bones [ more ]	0003100
Small hand	Disproportionately small hands	0200055
Syncope	Fainting spell	0001279
Toe syndactyly	Fused toes Webbed toes [ more ]	0001770
Triangular face	Face with broad temples and narrow chin Triangular facial shape [ more ]	0000325

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Do you have more information about symptoms of this disease? We want to hear from you.

Last updated: 2/1/2021

Do you have updated information on this disease? We want to hear from you.

Diagnosis Diagnosis

Yes, the Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Last updated: 8/18/2015

The diagnosis of Andersen-Tawil syndrome might be suspected in individuals with either:^[2]

1. Two of the following three criteria:

Periodic paralysis
Symptomatic cardiac arrhythmias or evidence of enlarged U-waves, ventricular ectopy, or a prolonged QTc or QUc interval on electrocardiogram (ECG)
Characteristic facial features, dental abnormalities, small hands and feet, and at least two of the following:
- Low-set ears
- Widely spaced eyes
- Small lower jaw (mandible)
- Fifth-digit clinodactyly (curved pinky finger)
- Syndactyly
  
  or

2. One of the above three criteria in addition to at least one other family member who meets two of the three criteria.

The presence of a mutation in the KCNJ2 gene confirms the diagnosis of Andersen-Tawil syndrome.^[2]

Last updated: 8/18/2015

Testing Resources

The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
Orphanet lists international laboratories offering diagnostic testing for this condition.

Find a Specialist Find a Specialist

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from MedlinePlus Genetics.

Research Research

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

ClinicalTrials.gov lists trials that are related to Andersen-Tawil syndrome. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
Orphanet lists European clinical trials, research studies, and patient registries enrolling people with this condition.

Organizations Organizations

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.

Organizations Supporting this Disease

Periodic Paralysis Association
155 West 68th Street
Apartment 1732
New York, NY 10023
Telephone: 407-339-9499
E-mail: lfeld@cfl.rr.com
Website: http://www.periodicparalysis.org
Periodic Paralysis International
2235 B 36th St. SW
Calgary, Alberta, T3E 2Z3 Canada
Telephone: +1-403-244-7213
E-mail: http://hkpp.org/contact
Website: http://www.hkpp.org
Sudden Arrhythmia Death Syndromes Foundation
4527 S 2300 E, Suite 104
Salt Lake City, UT 84117-4448
Telephone: 801-272-3022
Website: http://www.sads.org

Organizations Providing General Support

Muscular Dystrophy UK
61A Great Suffolk Street
London, SE1 0BU United Kingdom
Toll-free: 0800 652 6352 (Helpline)
Telephone: (+44) 0 020 7803 4800
E-mail: info@musculardystrophyuk.org
Website: https://www.musculardystrophyuk.org/

Do you know of an organization? We want to hear from you.

Learn More Learn More

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.

Where to Start

Genetics Home Reference (GHR) contains information on Andersen-Tawil syndrome. This website is maintained by the National Library of Medicine.
The National Heart, Lung, and Blood Institute (NHLBI) has information on this topic. NHLBI is part of the National Institutes of Health and supports research, training, and education for the prevention and treatment of heart, lung, and blood diseases.

In-Depth Information

GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
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 Andersen-Tawil syndrome. Click on the link to view a sample search on this topic.

Videos/Presentations

Identification and Treatment of Sudden Death Conditions in Young Patients. A presentation by David Bradley, M.D., Director, Pediatric Heart Rhythm Service, CS Mott Children's Hospital. Assoicate Professor, Department of Pediatrics and Communicable Diseases, University of Michigan.

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Have a question? Contact a GARD Information Specialist.

References References

Andersen-Tawil syndrome. Genetics Home Reference. April 2006; http://ghr.nlm.nih.gov/condition/andersen-tawil-syndrome. Accessed 8/18/2015.
Statland JM, Tawil R, Venance SL. Andersen-Tawil Syndrome. GeneReviews. August 6, 2015; http://www.ncbi.nlm.nih.gov/books/NBK1264/. Accessed 8/18/2015.

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