Metabolic Disorders Inborn errors of neurotransmitter metabolism
Aromatic L-amino Acid Decarboxylase (AADC) Deficiency
Rare Disease Classifications:
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.
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Emergency Management | Clinical Care Guidelines | Synonyms | Summary | Personal Stories | Symptoms | Cause/Inheritance | Diagnosis | Treatment | Clinical Care | Research and Data | Rare Disease Organisation(s) | Support Services/Resources | Mental Health | Other | References
Emergency Management
There may be special considerations for the emergency management of individuals living with AADC Deficiency presenting to emergency departments.
Clinical Care Guidelines
We are not aware of any clinical care guidelines for AADC Deficiency in Australia. If you know of any relevant care guidelines, please let us know via the Contribute page.
There is an international consensus guideline prepared by the iNTD and patient representatives – Consensus guideline for the diagnosis and treatment of aromatic l-amino acid decarboxylase (AADC) deficiency.2
Synonyms
Aromatic Amino Acid Decarboxylase Deficiency; AADC Deficiency; DDC Deficiency; Dopa Decarboxylase Deficiency
Summary
Aromatic L-amino Acid Decarboxylase (AADC) Deficiency is a condition caused by mutations in the dopa decarboxylase (DDC) gene that affects communication between cells in the body’s nervous system.1 The DDC gene is involved in the production of neurotransmitters, which are signals that allow the cells to talk to each other. When the neurotransmitters are not produced correctly, it prevents the nervous system from functioning properly. Symptoms of AADC Deficiency include difficulties in controlling movement of the head, face and neck, body temperature, blood pressure and heart rate.1
Personal Stories
Aromatic L-amino Acid Decarboxylase (AADC) Deficiency varies between individuals, and each person’s experience is unique.
If you would like to share your personal story with Rare Voices Australia and have it included on the RARE Portal, please visit Rare Voices Australia: Share Your Story.
Symptoms
Symptoms of AADC Deficiency may include difficulties in controlling movement of the head, face and neck, body temperature, blood pressure and heart rate.1
It is best to speak to your medical team to learn more about the symptoms and complications of AADC Deficiency.
There may be some symptoms that act as red flags to signal a rare genetic disease diagnosis. The Family GENES mnemonic is a useful resource for prompting clinicians to consider a rare genetic disease diagnosis.
Cause/Inheritance
AADC Deficiency is an autosomal recessive inherited disorder caused by genetic mutations in the DDC gene. The DDC gene is responsible for making the AADC enzyme that is involved in the production of neurotransmitters.
Factsheet: Autosomal recessive inheritance (NSW Government Health: Centre for Genetics Education)3
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.
Diagnosis
Diagnosis of AADC Deficiency may be established based on a spinal tap and blood test that show abnormalities in levels of neurotransmitters and enzymes related to the disorder. Genetic testing may be used to confirm the diagnosis. It is recommended that doctors use at least two of these methods to diagnose AADC Deficiency.2
A urine metabolic screen can also be performed to look for increased levels of urine vanillactic acid (VLA), which can be indicative of AADC Deficiency; however normal levels of VLA do not exclude an AADC Deficiency diagnosis.2
Further information about diagnostic tests for AADC Deficiency can be found in an international consensus guideline prepared by the International Working Group on Neurotransmitter Related Disorders (iNTD) and patient representatives – Consensus guideline for the diagnosis and treatment of aromatic l-amino acid decarboxylase (AADC) deficiency.2 It is best to speak to your medical team to learn more about the diagnostic tests available in Australia.
Treatment
It is best to speak with your medical team to learn more about possible treatment of AADC Deficiency and associated symptoms. Treatment will depend on an individual’s specific symptoms and complications.
Clinical Care
Healthcare professionals involved in the treatment of AADC Deficiency may include general practitioners (GP), paediatricians, geneticists, neurologists and metabolic physicians. The need for different healthcare professionals may change over a person’s lifetime and may extend beyond those listed here.
Research and Data
Please visit Australian Clinical Trials to learn about clinical trials for AADC Deficiency in Australia; there may not be any clinical trials currently available.
Information regarding clinical trials for AADC Deficiency 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.
The iNTD has a patient registry for neurotransmitter related disorders, which includes AADC Deficiency.
Rare Disease Organisation(s)
There are currently no known rare disease organisations/s supporting people living with AADC Deficiency in Australia. If you are aware of any AADC Deficiency organisations in Australia, please let us know via the Contribute page.
Global organisation supporting AADC Deficiency:
The AADC Research Trust
Website: https://www.aadcresearch.org/
Email: [email protected]
Other organisations:
Genetic Alliance Australia (GAA), Genetic Support Network of Victoria (GSNV) and Syndromes Without a Name (SWAN) Australia may be able to provide some support for families and individuals affected by an undiagnosed or rare genetic condition for which there is no disease specific organisation in Australia.
Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance.
Support Services/Resources
Please see the National and State Services pages.
Mental Health
Please see the ‘Mental Health’ sections listed on the National and State Services pages.
Other
Further information on AADC Deficiency can be found at:
Genetic and Rare Diseases (GARD) Information Center – Aromatic L-amino Acid Decarboxylase Deficiency
National Organization for Rare Disorders (NORD): Aromatic L-Amino Acid Decarboxylase Deficiency
References
- Genetic and Rare Diseases (GARD) Information Center. Aromatic L-amino Acid Decarboxylase Deficiency. Accessed May 12, 2022. https://rarediseases.info.nih.gov/diseases/770/aromatic-l-amino-acid-decarboxylase-deficiency
- Wassenberg T, Molero-Luis M, Jeltsch K, Hoffmann G, Assmann B, Blau N et al. Consensus guideline for the diagnosis and treatment of aromatic l-amino acid decarboxylase (AADC) deficiency. Orphanet. J. Rare Dis. [Internet]. 2017; 12:12. Available from: https://ojrd.biomedcentral.com/track/pdf/10.1186/s13023-016-0522-z?site=ojrd.biomedcentral.com.
- Autosomal Recessive Inheritance Factsheet. 2020. The Centre for Genetics Education. 6 p. Available from: https://www.genetics.edu.au/publications-and-resources/facts-sheets/fact-sheet-7-autosomal-recessive-inheritance
Page Last Updated
30/01/2023 11:45
