[MIM 271 245]

Acronym for Ophtalmoplegia-Hypotonia-Ataxia-Hypoacusis-Athetosis

(infantile onset spinocerebellar ataxia type 8, IOSCA)

Prevalence: < 1/106.  Mitochondrial cytopathy formerly classified as type 8 spinocerebellar ataxia. Autosomal recessive transmission of a mutation of the C10orf2 gene (10q 24). This results in a depletion of mitochondrial DNA coding for mitochondrial helicase in the cerebral and liver cells, but not the muscle cells. The described cases were of Finnish origin.

Clinical presentation:

-        early ataxia: onset between 9 and 18 months of age with athetosis and reduced tendon reflexes

-        ophthalmoplegia, and later optic atrophy

-        progressive sensorineural deafness

-        late onset, sometimes lethal, epilepsy that is resistant to treatment

Anesthetic implications:

deafness, epilepsy; see mitochondrial cytopathies

References : 

Updated: November 2018