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Disease Profile

Intermediate congenital nemaline myopathy

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
<1 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Neonatal

ICD-10

G71.2

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Intermediate congenital NM; Intermediate nemaline myopathy

Categories

Congenital and Genetic Diseases; Nervous System Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 171433

Definition
Intermediate nemaline myopathy is a type of nemaline myopathy (NM; see this term) that shows features of typical NM (see this term) in neonates with a more severe progression.

Epidemiology
The annual incidence of NM has been estimated at 1/50,000 live births, and intermediate NM might represent 20% of all cases.

Clinical description
Neonates with intermediate NM present with spontaneous anti-gravity movements and active respiratory muscles, but with a progressive generalized weakness which prevents achievement of gross motor milestones or leads to loss of ambulation and/or independent respiration by age 11 years. Children often develop joint contractures.

Etiology
The ACTA1 (1q42.13), NEB (2q22) or TPM3 (1q21.2) genes have been associated with intermediate NM and the transmission pattern of the disease is autosomal recessive or dominant.

Visit the Orphanet disease page for more resources.

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Generalized muscle weakness
0003324
Nemaline bodies
0003798
Severe muscular hypotonia
Severely decreased muscle tone
0006829
30%-79% of people have these symptoms
Abnormal thorax morphology
Abnormality of the chest
0000765
Decreased fetal movement
Less than 10 fetal movements in 12 hours
0001558
Difficulty walking
Difficulty in walking
0002355
Dysphagia
Poor swallowing
Swallowing difficulties
Swallowing difficulty

[ more ]

0002015
EMG: myopathic abnormalities
0003458
Hypokinesia
Decreased muscle movement
Decreased spontaneous movement
Decreased spontaneous movements

[ more ]

0002375
Hyporeflexia
Decreased reflex response
Decreased reflexes

[ more ]

0001265
Motor delay
0001270
Multiple prenatal fractures
Multiple fractures present at birth
Multiple fractures, present at birth
Numerous multiple fractures present at birth
Numerous multiple fractures that are present at birth

[ more ]

0005855
Myopathic facies
0002058
Polyhydramnios
High levels of amniotic fluid
0001561
Respiratory failure
0002878
Skeletal muscle atrophy
Muscle degeneration
Muscle wasting

[ more ]

0003202
Type 1 muscle fiber predominance
0003803
5%-29% of people have these symptoms
Areflexia
Absent tendon reflexes
0001284
Facial diplegia
0001349
High, narrow palate
Narrow, high-arched roof of mouth
Narrow, highly arched roof of mouth

[ more ]

0002705
Hypertelorism
Wide-set eyes
Widely spaced eyes

[ more ]

0000316
Long philtrum
0000343
Low-set ears
Low set ears
Lowset ears

[ more ]

0000369
Ophthalmoplegia
Eye muscle paralysis
0000602
Premature birth
Premature delivery of affected infants
Preterm delivery

[ more ]

0001622
1%-4% of people have these symptoms
Arthrogryposis multiplex congenita
0002804

Learn more

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.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.