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Start free with EleplanHallermann-Streiff syndrome
ORPHA:2108Malformation syndrome
Also called François dyscephalic syndrome · Oculomandibulofacial syndrome
What it is
Hallermann-Streiff syndrome is a rare genetic syndrome characterized mainly by head and facial abnormalities such as bird-like facies (with beak-shaped nose and retrognathia), hypoplastic mandible, brachycephaly with frontal bossing, dental abnormalities (e.g. absence of teeth, natal teeth, supernumerary teeth, severe agenesis of permanent teeth, enamel hypoplasia) hypotrichosis, various ophthalmic disorders (e.g. congenital cataracts, bilateral microphthalmia, ptosis, nystagmus) and atrophy of skin (especially around the center of face and nose) as well as telangiectasia and proportionate short stature. Intellectual disability is reported in some cases.
Key facts
- Prevalence
- 1-9 / 100 000 (at birth, Japan)
- Age of onset
- Antenatal, Infancy, Neonatal
- Inheritance
- Not applicable, Unknown
- Classified as
- Malformation syndrome
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Very common80–99%
14Common30–79%
16- Abnormality of hair texture
- Abnormality of the fontanelles or cranial sutures
- Abnormality of the tongue
- Glossoptosis
- High, narrow palate
- Malar flattening
- Micrognathia
- Narrow mouth
- Natal tooth
- Recurrent fractures
- Sparse eyebrow
- Sparse eyelashes
- Supernumerary tooth
- Telecanthus
- Underdeveloped nasal alae
- Visual impairment
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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