In slow-onset, chronic bilateral cases of vestibular dysfunction, these characteristic manifestations may be absent, and dysequilibrium may be the sole presentation. Causes
The three types of ataxia have overlapping causes, so can either coexist or occur in isolation. Cerebellar ataxia can have many causes despite normal neuroimaging. Focal lesions
Any type of focal lesion of the central nervous system (such as stroke, brain tumor, multiple sclerosis, inflammatory [such as sarcoidosis], and "chronic lymphocytyc inflammation with pontine perivascular enhancement responsive to steroids syndrome" [CLIPPERS]) will cause the type of ataxia corresponding to the site of the lesion: cerebellar if in the cerebellum; sensory if in the dorsal spinal cord...to include cord compression by thickened ligamentum flavum or stenosis of the boney spinal canal...(and rarely in the thalamus or parietal lobe); or vestibular if in the vestibular system (including the vestibular areas of the cerebral cortex). Exogenous substances (metabolic ataxia)
Exogenous substances that cause ataxia mainly do so because they have a depressant effect on central nervous system function. The most common example is ethanol (alcohol), which is capable of causing reversible cerebellar and vestibular ataxia. Chronic intake of ethanol causes atrophy of the cerebellum by oxidative and endoplasmic reticulum stresses induced by thiamine deficiency. Other examples include various prescription drugs (e.g. most antiepileptic drugs have cerebellar ataxia as a possible adverse effect), Lithium level over 1.5mEq/L, synthetic cannabinoid HU-211 ingestion and various other medical and recreational drugs (e.g. ketamine, PCP or dextromethorphan, all of which are NMDA receptor antagonists that produce a dissociative state at high doses).
Onasemnogene abeparvovec, sold under the brand name Zolgensma, is a gene therapy medication used to treat spinal muscular atrophy (SMA). It is used as a one-time infusion into a vein.Onasemnogene abeparvovec works by providing a new copy of the gene that makes the human SMN protein.The treatment must be accompanied by a course of corticosteroids of at least two months. Common side effects include vomiting and increased liver enzymes.Onasemnogene abeparvovec was first approved for medical use in the United States in 2019 as a treatment for children less than two years old. It was later approved in other jurisdictions with similar scope. The approval scope in certain jurisdictions, including the European Union and Canada, is somewhat different. Medical uses
Onasemnogene abeparvovec has been developed to treat spinal muscular atrophy, a disease linked to a mutation in the SMN1 gene on chromosome 5q and diagnosed predominantly in young children that causes progressive loss of muscle function and frequently death. The medication is administered as an intravenous infusion.The treatment is approved in the United States and certain other countries for use in children with spinal muscular atrophy up to the age of two, including at the presymptomatic stage of the disease. In the European Union and Canada, it is indicated for the treatment of patients with spinal muscular atrophy who either have a clinical diagnosis of spinal muscular atrophy type 1 or have up to three copies of the SMN2 gene.The medication is used with corticosteroids in an effort to protect the liver.