Caring for someone with this diagnosis? Eleplan keeps diagnoses, medications, documents and every specialist in one plan.
Start free with EleplanSporadic adult-onset ataxia of unknown etiology
ORPHA:247234Disease
Also called Idiopathic late-onset cerebellar ataxia · SAOA
What it is
A rare non-hereditary degenerative ataxia disease characterized by a slowly progressive cerebellar syndrome (with ataxia of stance and gait, upper limb dysmetria and intention tremor, ataxic speech, and oculomotor abnormalities), presenting in adulthood (at around 50 years of age), that is not due to a known cause. Extracerebellar symptoms (e.g., decreased vibration sense and absent or decreased ankle reflexes), polyneuropathy and mild autonomic dysfunction may also be present. Mild cognitive impairment has also rarely been reported.
Key facts
- Prevalence
- 1-9 / 100 000 (Italy)
- Age of onset
- Adult, Elderly
- Inheritance
- 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
Common30–79%
8Sometimes5–29%
14- Abnormal cranial nerve morphology
- Akinesia
- Babinski sign
- Dysarthria
- Dysdiadochokinesis
- Dysphagia
- Hyperreflexia
- Hypomimic face
and 6 more in this range
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.
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.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
Powered by Eleplan
A rare diagnosis is just the start. Eleplan keeps the whole care plan in one place.
Diagnoses, medications, documents, appointments, and the whole care team — organized and always in sync, so you are not retelling the same story to every new specialist. With Ellie, your AI care assistant, on top of it. Free to start.