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GTR Home > Conditions/Phenotypes > Episodic ataxia, type 9

Episodic ataxia, type 9

Summary

Episodic ataxia type 9 (EA9) is a neurologic disorder characterized by onset of ataxic episodes in the first years of life. Features may include difficulty walking, dizziness, slurred speech, headache, vomiting, and pain. The ataxic episodes vary in frequency and duration; most tend to occur every few weeks or months and last minutes to hours. Prior to the EA, most patients have neonatal- or infantile-onset tonic or generalized tonic-clonic (GTC) seizures that may be severe and refractory to medication, but remit later in infancy or early childhood, either spontaneously or concurrently with medication. Some patients have mildly delayed development with speech delay and/or autistic features or mildly impaired intellectual development. However, others show normal psychomotor development. Treatment of the ataxic episodes with acetazolamide is effective in about 50% of patients (summary by Schwarz et al., 2019). For a phenotypic description and discussion of genetic heterogeneity of episodic ataxia, see EA1 (160120). [from OMIM]

Available tests

16 tests are in the database for this condition.

Clinical tests (16 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: BFIC3, BFIS3, BFNIS, DEE11, EA9, EIEE11, HBA, HBSCI, HBSCII, NAC2, Na(v)1.2, Nav1.2, SCN2A1, SCN2A2, SCN2A
    Summary: sodium voltage-gated channel alpha subunit 2

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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