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AADC deficiency symptom overview

What are the signs and symptoms of AADC Deficiency?

If your child has low muscle tone that is unexplained and not improving, there are other symptoms you can look for to help you decide if you should talk with your child’s doctor about AADC Deficiency or other similar conditions.

Symptoms of AADC Deficiency

A child with AADC Deficiency may have some or all of the following symptoms. Of course, every child is different, so your child’s symptoms may vary.

The most common symptoms are:

  • Low muscle tone, also called “hypotonia,” is the most common symptom
  • Delays in development. A child with AADC Deficiency may be unable to:
    • Lift and control his or her head
    • Crawl, sit, or stand without support
    • Walk
    • Babble or say words

Many children with AADC Deficiency also have movement problems, including:

  • Involuntary eye movements (called oculogyric crises). These are moments when a child’s eyes suddenly roll upward involuntarily. They can last anywhere from a few seconds to hours, and can happen several times a day or several times a week. When this happens, it can look like the child is having a seizure

View this short video to see what 
oculogyric crises look like

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  • Other involuntary movements, such as sudden jerking, flailing, or twisting
  • Other common symptoms you might notice are excessive sweating, drooling, drooping eyelids, or a stuffy or runny nose

These symptoms may also be present:

  • Seizures
  • Difficulty sleeping
  • Behavioral problems (like irritability or excessive crying)
  • Problems with digestion
    • Diarrhea
    • Constipation
    • Reflux
  • Problems with feeding
    • Trouble swallowing without choking or coughing

Download a symptom questionnaire that will help you discuss your child’s condition with his or her doctor

Download Questionnaire

Read patient stories of 2 children who were diagnosed with AADC Deficiency