Alternating hemiplegia of childhood

What it is

A rare neurological syndrome characterized by episodes of hemiplegia (alternating between the two sides of the body) or tetraplegia, and other accesses such as abnormal ocular movements, dystonia, and dysautonomia. Patients have permanent neurological impairment, variable degrees of intellectual disability, movement disorders, and psychiatric problems. Half of them present with epilepsy.

Key facts

Prevalence

1-9 / 1 000 000 (at birth, Denmark)

Age of onset

Infancy, Neonatal

Inheritance

Autosomal dominant, Not applicable

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.

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.

Cross-references