Congenital myopathy with myasthenic-like onset

What it is

Congenital myopathy with myasthenic-like onset is a rare, genetic, non-dystrophic myopathy characterized by fatigable muscle weakness associated with congenital myopathy. Patients present with axial hypotonia, myopathic facies with fatigable ptosis, feeding difficulties, delayed gross motor development and proximal limb weakness with a RYR1-related typical pattern of muscle involvement (i.e. severe involvement of the soleus muscle and sparring of the rectus femoris, sartorius, gracilis and semitendinous muscles). Scoliosis and frequent respiratory tract infections are additional observed features.

Key facts

Prevalence

<1 / 1 000 000

Age of onset

Infancy, Neonatal

Inheritance

Autosomal recessive

Classified as

Disease

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

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.

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