The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.
| Signs and Symptoms | Approximate number of patients (when available) |
| Abnormality of the neck | 90% |
| Cognitive impairment | 90% |
| Hyperreflexia | 90% |
| Hypoplasia of the zygomatic bone | 90% |
| Incoordination | 90% |
| Narrow face | 90% |
| Narrow forehead | 90% |
| Neurological speech impairment | 90% |
| Skeletal muscle atrophy | 90% |
| Upslanted palpebral fissure | 90% |
| Gait disturbance | 50% |
| Limitation of joint mobility | 50% |
| Macrotia | 50% |
| Open mouth | 50% |
| Single transverse palmar crease | 50% |
| Camptodactyly of finger | 7.5% |
| Cerebral calcification | 7.5% |
| Proptosis | 7.5% |
| Ptosis | 7.5% |
| Scoliosis | 7.5% |
| Type I diabetes mellitus | 7.5% |
| Rotary nystagmus | 5% |
| Abnormal conjugate eye movement | - |
| Abnormality of the rib cage | - |
| Ataxia | - |
| Babinski sign | - |
| Clonus | - |
| Congenital onset | - |
| Delayed CNS myelination | - |
| Drooling | - |
| Dysarthria | - |
| Feeding difficulties in infancy | - |
| Flexion contracture | - |
| Generalized amyotrophy | - |
| Hallux valgus | - |
| Hypothyroidism | - |
| Inability to walk | - |
| Intellectual disability, progressive | - |
| Intellectual disability, severe | - |
| Involuntary writhing movements | - |
| Irritability | - |
| Leukodystrophy | - |
| Microcephaly | - |
| Neonatal hypotonia | - |
| Pectus excavatum | - |
| Pes planus | - |
| Prominent antihelix | - |
| Severe global developmental delay | - |
| Spastic paraplegia | - |
| Spastic tetraplegia | - |
| Stahl ear | - |
| Thyroid-stimulating hormone excess | - |
| X-linked dominant inheritance | - |
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.
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.
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Is cleft lip and/or palate frequently present in Allan-Herndon-Dudley syndrome? See answer
