Neurological Diseases; Diseases of the Immune System
Ataxia-Telangiectasia (A-T)
IMPORTANT INFORMATION
The information on the Rare Awareness Rare Education (RARE) Portal is intended for educational purposes only and does not replace professional advice.
Rare diseases typically display a high level of symptom complexity and variability. Individuals diagnosed with the same rare disease may be impacted differently and each person’s experience is unique. Please seek support from qualified healthcare professionals to learn more about the most suitable care and support options for you.
For more information on this disease, please refer to RVA Partner, BrAshA-T Ataxia-Telangiectasia Limited.1
If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.
Contributors
This page has been co-developed with RVA Partner, BrAshA-T Ataxia-Telangiectasia Limited.1
Quick Page Search:
Emergency Management | Clinical Care Guidelines | Synonyms | Summary | Personal Stories | Symptoms | Cause/Inheritance | Diagnosis | Treatment | Clinical Care | Research | Rare Disease Organisation(s) | Support Services/Resources | Mental Health | Other | References
Emergency Management
There are special considerations for the emergency management of individuals living with Ataxia-telangiectasia (A-T) and when presenting to emergency departments.
Below are a few considerations for when treating a patient with A-T:
- Individuals have a weakened immune system and are at high risk of infections2,3
- Increased sensitivity to radiation. Exposure to radiation (such as X-rays) should be avoided or minimised as much as possible3,4
- May be adversely affected by anaesthesia and prone to impaired swallowing, increased risk of aspiration, reduced pulmonary function, and infection5
Clinical Care Guidelines
Clinical Care Guidelines for Ataxia telangiectasia (A-T) are yet to be developed in Australia.
Development of cancer surveillance guidelines in ataxia telangiectasia: A Delphi‐based consensus survey of international experts is an international consensus statement developed and published in 2023 by experts from 13 countries, including Australia.
Below are recommended A-T management guidelines by specialists from other countries:
- European Respiratory Society (ERS, published in 2015) – ERS statement on the multidisciplinary respiratory management of ataxia telangiectasia
- Netherlands (published in 2017) – Ataxia‐telangiectasia: recommendations for multidisciplinary treatment
- United States (published in 2021) – Multidisciplinary Management of Ataxia Telangiectasia: Current Perspectives
Synonyms
Louis-Bar Syndrome
ORPHA:100
ICD-11: 4A01.31
Summary
Ataxia-telangiectasia (A-T) is a genetic condition caused by mutations in the ATM gene that is involved in cellular processes in the body, such as response to DNA damage and in DNA repair.4 Hallmarks of A-T include3-6:
- Progressive cerebellar ataxia – loss of ability to control movement of muscles that affects balance and coordination, eye movements, swallowing, and speech, which worsens over time
- Telangiectasia – widened (dilated) blood vessels that appear as visible red or pink lines, usually in the eyes or on the skin, particularly areas that are exposed to the sun
- Immunodeficiency – weakened immune system, resulting in higher risk of infections
- Increased risk of cancer
Symptoms of A-T may present at different stages of life, with the ataxia beginning between 1-4 years3, whilst the telangiectasia is usually observed after 5 years of age.6 The cerebellar ataxia is caused by cerebellar degeneration6, which is the loss of cells in the cerebellum, the part of the brain that controls movement and coordination. It is progressive, with symptoms worsening over time.3-6 Children are initially observed to be wobbly on their feet but may gradually lose their ability to walk, with many progressing to needing a wheelchair. Other symptoms include impaired eye coordination (oculomotor apraxia) making it hard to read, involuntary movements (choreoathetosis), and progressively slurred speech (dysarthria).3
A multi-disciplinary medical team is required for the management of A-T, which will include careful monitoring of immune function and for infections, as well as for cancer.4,5
Useful Links for Professionals
GeneReviews®: Ataxia-Telangiectasia
Online Mendelian Inheritance in Man (OMIM): #208900; ATAXIA-TELANGIECTASIA; AT
Orphanet: Ataxia telangiectasia
Human Phenotype Ontology (HPO): Ataxia-telangiectasia [OMIM:208900]
Human Phenotype Ontology (HPO): Ataxia-telangiectasia [ORPHA:100]
Symptoms
Symptoms associated with Ataxia-telangiectasia (A-T) begin to present between 1-4 years of age, starting with the features of ataxia – being unsteady when walking (wobbly gait), as well as lack of balance and coordination.3,6 The children often lose their ability to walk over time and may require a wheelchair by the time they turn 10.4,5 Other symptoms that affect motor skills include impaired eye coordination (oculomotor apraxia) making it hard to read, involuntary movements (choreoathetosis), and progressively slurred speech (dysarthria).3,5,6
The other distinctive feature of A-T is the dilated blood vessels (telangiectasia) that usually presents between 5-8 years of age. This can be seen in the eyes, or on the skin in areas that are exposed to the sun.3,6
Individuals with A-T have a weakened immune system and are prone to developing infections, particularly in the chest and lungs.3 They also have increased risk of developing cancers, such as lymphomas and leukemias during childhood, and cancers in solid organs (gastric, breast, pancreatic and skin cancers) in adulthood.4
Cause/Inheritance
Ataxia-telangiectasia (A-T) is a genetic condition. It is caused by mutations in the ATM gene.
A-T is inherited in an autosomal recessive manner. Information about autosomal recessive inheritance can be found at: Factsheet: Autosomal recessive inheritance (NSW Government Health: Centre for Genetics Education).
If you would like to learn more about the inheritance and impact of this condition, please ask your doctor for a referral to a genetic counsellor. Genetic counsellors are qualified allied health professionals who can provide information and support regarding genetic conditions and testing. More information on genetic counselling can be found on the National Services page and specific State and Territory Services pages on the RARE Portal.
Information about the ATM gene: it is involved in repairing double-stranded breaks that can occur in a person’s DNA, as well as in the response to oxidative stress in cells of the body. Defects in the ATM gene can result in genomic instability and DNA damage.6
Diagnosis
Diagnosis of Ataxia-telangiectasia (A-T) may be made based on clinical examination, family history, and genetic testing for mutations (including deletions or duplications) in the ATM gene.3,6
An A-T diagnosis is often suspected based on characteristic features of A-T, including but not limited to, ataxia, abnormal control of eye movement, postural instability, telangiectasia, and frequent infections.6 An A-T diagnosis can sometimes be missed in young children, as they may not yet exhibit all of the characteristic features.5 It has been recommended that a A-T diagnosis should be carefully considered for any child with ataxia that has no other identified causes.6
Individuals with A-T can have increased levels of serum alpha-fetoprotein (AFP), and some have reduced levels of immunoglobulins (such as IgG and IgA), which are an important part of the body’s immune defence system.5
Please speak to your medical team to learn more about the available diagnostic tests for A-T.
Treatment
There is currently no curative treatment for Ataxia-telangiectasia (A-T), but there are strategies to assist in the management of symptoms. This may involve a multidisciplinary team and could include lifelong care. Management strategies may include physical and occupational therapy and use of feeding tubes for those with difficulties with swallowing.5 Intravenous immunoglobulin (IVIG) replacement therapy may be used for those with frequent, severe infections and low levels of immunoglobulin G (IgG, an antibody blood protein involved in protecting the body from infections).3,5
Monitoring of immune function, recurrent infections, pulmonary function, swallowing, nutrition, and scoliosis (sideways curvature of the spine),7 as well as for early signs of cancer are recommended.5
As individuals with A-T have increased sensitivity to radiation, cancer treatment (such as radiotherapy and certain types of chemotherapeutic agents) should be administered with caution. Lower doses of treatment may be required, as normal doses may be toxic or lethal.3,5
Individuals with A-T may have an adverse effect to anaesthesia, which may affect their breathing and swallowing, and need to be monitored carefully during and after surgery.5
Please speak with your medical team to learn more about suitable management strategies for A-T.
Clinical Care
Healthcare professionals involved in the treatment of Ataxia-telangiectasia (A-T) may include general practitioners (GP), paediatricians, geneticists, allergists/immunologists, dermatologists, endocrinologists, neurologists, oncologists, ophthalmologists, psychiatrists, and physical and occupational therapists.1,2 The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.
National A-T Clinic
Wesley Medical Research Centre and Queensland Children’s Hospital
The A-T clinic provides a team of expert doctors who aim to see every child in Australia diagnosed with A-T. Specialist doctors in attendance are from the areas of neurology, immunology, respiratory, genetics, ophthalmology and dermatology, as well as allied health therapists.
Please visit The National A-T Clinic (brashat.org.au) for more information.
Research
Information about research on Ataxia-telangiectasia (A-T) in Australia can be found at BrAshA-T Ataxia-Telangiectasia Limited: Research.
Please visit Australian Clinical Trials to learn about clinical trials for A-T in Australia; there may not be any clinical trials currently available.
Information regarding clinical trials for A-T in other countries can be found at ClinicalTrials.gov; there may not be any clinical trials currently available.
It is best to discuss your interest in any clinical trials with your medical team to determine suitability and eligibility.
Rare Disease Organisation(s)
BrAshA-T Ataxia-Telangiectasia Limited (BrAshA-T) RVA PartnerAustralian Organisation
Website: https://brashat.org.au/
Email: [email protected]
BrAshA-T is a charitable foundation created to raise money to support research into finding a cure and as a means for creating a support network for other families dealing with A-T.
International Organisation:
A-T Global Alliance
Website: https://cureat.org/
The Global A-T Alliance aims to maximise the effort, resources and/or funding committed to finding a cure or treatments for Ataxia-Telangiectasia (A-T) worldwide.
Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance.
Support Services/Resources
Please visit the National and State Services pages.
Mental Health
Please visit the ‘Mental Health’ sections listed on the National and State Services pages.
Other
Further information on Ataxia-telangiectasia (A-T), or childhood dementia disorders, can be found at:
- Genetic and Rare Diseases (GARD) Information Center – Ataxia-telangiectasia
- National Organization for Rare Disorders (NORD): Ataxia Telangiectasia
References
- BrAshA-T Ataxia-Telangiectasia Limited. Accessed 6 September 2023. https://brashat.org.au
- Genetic and Rare Diseases (GARD) Information Center. Ataxia-telangiectasia. Accessed 6 September 2023. https://rarediseases.info.nih.gov/diseases/5862/ataxia-telangiectasia
- National Organization for Rare Disorders (NORD). Ataxia Telangiectasia. Accessed 6 September 2023. https://rarediseases.org/rare-diseases/ataxia-telangiectasia/
- McGrath-Morrow SA, Rothblum-Oviatt CC, Wright J, et al. Multidisciplinary management of Ataxia Telangiectasia: Current perspectives. J. Multidiscip. Healthc. 2021; 14:1637-1644. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8253936/
- Gatti R, Perlman S. Ataxia-Telangiectasia. 1999 [Updated 27 October 2016]. In: Adam MP, Mirzaa GM, Pagon RA, et al., ed. GeneReviews® [Internet]. Seattle, WA; 1993-2023. Gatti R, Perlman S. Ataxia-Telangiectasia. 1999 [Updated 27 October 2016]. In: Adam MP, Mirzaa GM, Pagon RA, et al., ed. GeneReviews® [Internet]. Seattle, WA; 1993-2023. https://www.ncbi.nlm.nih.gov/books/NBK26468/
- Rothblum-Oviatt C, Wright J, Lefton-Greif MA, et al. Ataxia telangiectasia: a review. Orphanet J. Rare Dis. 2016; 11(159). https://doi.org/10.1186/s13023-016-0543-7
- Bhatt JM, Bush A, van Gerven M, et al. ERS statement on the multidisciplinary respiratory management of ataxia telangiectasia. Eur. Respir. Rev. 2015;24(168):565-581. https://doi.org/10.1183/16000617.0066-2015
Page Last Updated
16/10/2023 08:47
