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Don’t fight Aromatic L-amino acid decarboxylase deficiency alone.
Find your community on the free RareGuru App.Aromatic l-amino acid decarboxylase (AADC) deficiency is a disease that affects the production of signals that allow cells in the nervous system to communicate with each other. These signals are called neurotransmitters. When the neurotransmitters are not being produced correctly, there are problems with the nervous system. Individuals affected by this disease often have trouble coordinating movements, especially of the head, face, and neck. Other symptoms of the condition include problems controlling blood pressure, heart rate, and body temperature.
AADC deficiency is caused by mutations in the DDC __ gene. The disease is inherited in an autosomal recessive manner. Diagnosis of the disease may be established based on a spinal tap and a blood test that show abnormalities in levels of neurotransmitters and enzymes related to the disorder. Genetic testing may be used to confirm the diagnosis. Treatment of the disease may include a variety of medications which may result in varying levels of success in individual patients. Physical, occupational, and speech therapy may also be of benefit.
Source: GARD Last updated on 05-01-20
Symptoms of aromatic l-amino acid decarboxylase (AADC) deficiency typically present during the first year of life. Symptoms may include severe delay in reaching milestones such as walking and talking (developmental delay), weak muscle tone (hypotonia), muscle stiffness, difficulty moving, and involuntary writhing movements of the limbs (athetosis). This condition may also cause infants to lack energy, feed poorly, startle easily, and have sleep disturbances.
Many people with AADC deficiency experience episodes called oculogyric crises (also called "spells" or "attacks"), which are characterized by abnormal rotation of the eyeballs, extreme irritability and agitation, pain, muscle spasms, and uncontrolled movements of the head and neck.. These episodes can last for many hours and can be times of extreme concern for caregivers and family members.
AADC deficiency may also affect the autonomic nervous system, which controls involuntary body processes like regulation of blood pressure and body temperature. Autonomic symptoms may include droopy eye lids (ptosis), constriction of the pupils of the eyes (miosis), inappropriate or impaired sweating, nasal congestion, drooling, reduced ability to control body temperature, low blood pressure (hypotension), gastroesophageal reflux, low blood sugar (hypoglycemia), fainting (syncope), and cardiac arrest.
The signs and symptoms of AADC deficiency tend to worsen late in the day or when the individual is tired, and symptoms tend to improve after sleep.
Last updated on 05-01-20
Aromatic l-amino acid decarboxylase (AADC) deficiency is caused by changes (mutations) in the DDC __gene. This gene provides instructions to the body to create an enzyme called the AADC enzyme. When this enzyme is working properly, it creates neurotransmitters called dopamine and serotonin. These neurotransmitters allow the cells of the nervous system to communicate with each other properly.
When there is a mutation in DDC , the body does not create AADC enzyme correctly, and there are not enough properly working neurotransmitters in the body. These changes therefore cause the symptoms associated with AADC deficiency.
Last updated on 05-01-20
Aromatic l-amino acid decarboxylase (AADC) deficiency is typically diagnosed based on a number of laboratory tests. A spinal tap may be completed to measure levels of substances related to having low levels of dopamine and serotonin. A blood sample can also be taken to measure the activity of the AADC enzyme.
If these tests are consistent with an individual having AADC deficiency, genetic testing can be completed to confirm the diagnosis. It is recommended that doctors use at least two of these methods to diagnose a person with AADC deficiency.
Last updated on 05-01-20
Aromatic l-amino acid decarboxylase (AADC) deficiency is inherited in an autosomal recessive manner. This means that both copies of the DDC gene must be changed in order to have symptoms of the disease. We inherit one copy of each gene from our mother and the other from out father.
People with a mutation in only one copy of the DDC gene are known as carriers. When two carriers of AADC deficiency have children together, for each child there is a:
Last updated on 05-01-20
There is limited information available about the long-term outlook for people diagnosed with aromatic l-amino acid decarboxylase (AADC) deficiency. There can be a wide variation in the severity of symptoms in people with the disease. It is not expected that the severity of symptoms should increase as an affected individual gets older. However, in some cases new symptoms may develop as side effects to other symptoms. For example, some people with AADC deficiency may develop joint contractures (inability to move joints) due to the movement disorders associated with the disease.
Some of the symptoms associated with AADC deficiency, such as problems controlling the autonomic nervous system, may be life-threatening in moments of stress. It is important to follow the doctor’s recommendations for monitoring the symptoms of people with AADC deficiency and to know what to do in case of an emergency.
Last updated on 05-01-20
There is currently no cure for aromatic L-amino acid decarboxylase (AADC) deficiency. Different medications can be used to help treat the signs and symptoms of the disease. However, although certain combinations of medications may help some people, there is no proven strategy that relieves the symptoms of all people with this disease. Whether or a not a treatment works may depend on the exact change in the DDC gene and how much the AADC enzyme is functioning in the body.
Since the nervous system in a child with AADC deficiency does not have enough of certain neurotransmitters, the goal of many of the treatments is to make certain as much of these neurotransmitters are available as possible.
Medication could include any one or combination of the following:
Other treatments may depend on the symptoms of each individual. These treatment options include:
Physical, occupational, and speech therapy may also be helpful in improving symptoms of the disease.
Gene therapy treatment for AADC deficiency seems promising and clinical studies in humans are currently underway.
Last updated on 05-01-20
Kojima K, Nakajima T, Taga N, et. al. Gene therapy improves motor and mental function of aromatic l-amino acid decarboxylase deficiency. Brain. 2019 Feb 1;142(2):322-333.
Last updated on 04-27-20
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