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.
|Medical Terms||Other Names||
|30%-79% of people have these symptoms|
|Intellectual disability, severe||
Early and severe mental retardation
Mental retardation, severe
Severe mental retardation[ more ]
|Progressive extrapyramidal movement disorder||0007153|
|Severe global developmental delay||0011344|
|5%-29% of people have these symptoms|
|Abnormal head movements||0002457|
Aggressiveness[ more ]
Involuntary writhing movements in fingers, hands, toes, and feet
|Bilateral tonic-clonic seizure||
Grand mal seizures
|Focal impaired awareness seizure||0002384|
|Generalized myoclonic seizure||0002123|
More active than typical
|1%-4% of people have these symptoms|
Low or weak muscle tone
|Percent of people who have these symptoms is not available through HPO|
|Delayed speech and language development||
Deficiency of speech development
Delayed language development
Delayed speech acquisition
Delayed speech development
Impaired speech and language development
Impaired speech development
Language development deficit
Late-onset speech development
Poor language development
Speech and language delay
Speech and language difficulties
Speech delay[ more ]
|Global developmental delay||0001263|
|Infantile muscular hypotonia||
Decreased muscle tone in infant
Mental retardation, nonspecific
Mental-retardation[ more ]
|Reduced brain creatine level by MRS||0025051|
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.
Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.
Conditions with similar signs and symptoms from Orphanet
The differential diagnosis in children with a cerebral creatine deficiency includes L-Arginine:glycine amidinotransferase (AGAT) deficiency and X-linked creatine transporter deficiency. In the case of a partial cerebral creatine deficiency, argininosuccinic aciduria, citrullinemia type I, and gyrate atrophy of the choroid and retina (see these terms) should be considered.
Visit the Orphanet disease page for more information.
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.
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.
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