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||
|80%-99% of people have these symptoms|
|Abnormality of the neck||0000464|
Absent speech development
Lack of language development
Lack of speech
No speech development
No speech or language development
Nonverbal[ more ]
Difficulty finding words
Loss of words[ more ]
Loss of bowel control
|Hypoplasia of the musculature||
Poorly developed skeletal musculature
Underdeveloped muscle[ more ]
|Hypoplasia of the zygomatic bone||
Decreased size of cheekbone
Underdevelopment of cheekbone[ more ]
|Inability to walk||0002540|
|Intellectual disability, progressive||
Mental retardation, progressive
Progressive mental retardation[ more ]
|Intellectual disability, severe||
Early and severe mental retardation
Mental retardation, severe
Severe mental retardation[ more ]
Decreased breadth of face
Decreased width of face[ more ]
|Skeletal muscle atrophy||
Muscle wasting[ more ]
|Upslanted palpebral fissure||
Upward slanting of the opening between the eyelids
Loss of bladder control
|30%-79% of people have these symptoms|
|Bilateral single transverse palmar creases||0007598|
Stiff joints[ more ]
Gaped jawed appearance
Gaped mouthed appearance
Slack jawed appearance[ more ]
|5%-29% of people have these symptoms|
|Camptodactyly of finger||
Permanent flexion of the finger
Abnormal deposits of calcium in the brain
Eyeballs bulging out
Protruding eyes[ more ]
Prominent ears[ more ]
Drooping upper eyelid
Abnormal curving of the spine
Type 1 diabetes
Type I diabetes[ more ]
|Percent of people who have these symptoms is not available through HPO|
|Abnormal conjugate eye movement||0000549|
Symptoms present at birth
Difficulty articulating speech
|Feeding difficulties in infancy||0008872|
Diffuse skeletal muscle wasting
Generalized muscle degeneration
Muscle atrophy, generalized[ more ]
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference[ more ]
Decreased width of the forehead
Low muscle tone, in neonatal onset
Flat foot[ more ]
Vulcan ear[ more ]
|Underfolded superior helices||0008583|
Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.
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
Differential diagnoses include X-linked intellectual disability conditions associated with ataxia, spastic paraplegia or muscle hypoplasia such as X-linked intellectual disability-spastic paraplegia with iron deposits syndrome, X-linked progressive cerebellar ataxia, and spastic paraplegia type 2. Pelizaeus-Merzbacher disease and Snyder-Robinson syndrome should also be considered.
Visit the Orphanet disease page for more information.
Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.
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.
Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question
Is cleft lip and/or palate frequently present in Allan-Herndon-Dudley syndrome? See answer