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Start free with EleplanMicrocephalic primordial dwarfism, Montreal type
ORPHA:2617Malformation syndrome
Also called Bird-headed dwarfism, Montreal type
What it is
A rare, genetic multiple congenital anomalies/dysmorphic syndrome characterized by severe short stature and craniofacial dysmorphism (microcephaly, narrow face with flat cheeks, ptosis, prominent nose with a convex ridge, low-set ears with small or absent lobes, high-arched/cleft palate, micrognathia), associated with premature graying and loss of scalp hair, redundant, dry and wrinkled skin of the palms, premature senility and varying degrees of intellectual disability. Cryptorchidism and skeletal anomalies may also be observed. There have been no further descriptions in the literature since 1970.
Key facts
- Prevalence
- <1 / 1 000 000
- Age of onset
- Infancy, Neonatal
- 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%
30- Abnormal dermatoglyphics
- Abnormal hair quantity
- Abnormal palate morphology
- Alopecia of scalp
- Carious teeth
- Congenital pyloric atresia
- Convex nasal ridge
- Cryptorchidism
- Dry skin
- EEG abnormality
- Hyperhidrosis
- Hyperreflexia
- Hypertonia
- Intellectual disability
- Kyphosis
- Lipoatrophy
- Low posterior hairline
- Microcephaly
- Micrognathia
- Open bite
- Posteriorly rotated ears
- Premature graying of hair
- Prematurely aged appearance
- Ptosis
- Reduced bone mineral density
- Scoliosis
- Severe short stature
- Shagreen patch
- Vertebral segmentation defect
- Wide intermamillary distance
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.
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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