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Start free with EleplanCongenital fiber-type disproportion myopathy
ORPHA:2020Disease
Also called CFTDM
What it is
A rare genetic, congenital, non-dystrophic myopathy characterized by neonatal or infantile-onset hypotonia and mild to severe generalized muscle weakness.
Key facts
- Age of onset
- Infancy, Neonatal
- Inheritance
- Autosomal dominant, Autosomal recessive, X-linked recessive
- Classified as
- Disease
Recorded for the broader condition
- Prevalence
- 1-9 / 100 000 (United States)Congenital myopathy
Orphanet records these for the broader condition rather than for this specific form. They are a starting point, not a figure for this subtype — subtypes often differ, and some are defined by being rarer than the condition they sit under.
Signs and symptoms
Common30–79%
21- Abnormality of skeletal morphology
- Abnormality of the respiratory system
- Areflexia
- Dental crowding
- Dysphagia
- Easy fatigability
- Failure to thrive
- Fatigable weakness of bulbar muscles
- Fatigue
- Feeding difficulties
- Flexion contracture
- High palate
- Motor delay
- Myopathic facies
- Poor appetite
- Poor head control
- Reduced tendon reflexes
- Respiratory insufficiency due to muscle weakness
- Weakness of facial musculature
- Weakness of muscles of respiration
- Weight loss
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.
Genes
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.
Benefit programs to look at
Programs whose eligibility touches the same ICD-10 categories. Eligibility is decided by the administering agency, never by this page.
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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