- Ataxia is impaired coordination in the absence of weakness.
- Acute ataxia is a neurological emergency, and vascular lesions of the cerebellum (infarction, hemorrhage) must be considered/ excluded.
Acute onset (minutes/ hours)
- cerebellar hemorrhage or infarction (particularly suspect this if hemiataxia or other brainstem signs)
- Intoxication with alcohol or drugs is perhaps the most common etiology (truncal/ gait, bilateral, altered mental state)
— e.g. alcohol, antiepileptics
- Migraine (basilar migraine variant can present with cerebellar ataxia and brainstem signs; headache may not be prominent)
Subacute ataxia (hours/days)
- Infectious causes: most common in children
— viral cerebellitis, especially 2–10 years old (pyrexia, limb/gait ataxia, and dysarthria, with recovery over a period of weeks)
— Postinfectious encephalomyelitis, especially varicella.
- Intoxication (see acute)
- Multiple sclerosis, consider this especially in young adults (history of relapse, other brainstem signs)
- Paraneoplastic syndromes (especially neuroblastoma in children and lung carcinoma in adults)
— Foramen magnum compression
— Labyrinthitis/vestibular neuritis ( vertigo, nausea, and vomiting are more prominent)
— Miller-Fisher variant of Guillain-Barré syndrome (ophthalmoplegia, ataxia, areflexia)
— Posterior fossa lesions (features of increased intracranial pressure)
- Autosomal dominant spinocerebellar ataxias (SCA)
- Recessively inherited and X-linked ataxias
— ataxia telangiectasia
— Friederich ataxia
— other rare causes
References and Links
- Bhidayasiri R, Waters MF, Giza CC. Neurological differential diagnosis: a prioritized approach, Blackwell Publishing 2005.