Peripheral Neuropathy in Spinocerebellar Ataxia Type 1, 2, 3, and 6.
Spinocerebellar ataxias (SCAs) are characterized by autosomal dominantly inherited progressive ataxia but are clinically heterogeneous due to variable involvement of non-cerebellar parts of the nervous system. Non-cerebellar symptoms contribute significantly to the burden of SCAs, may guide the clinician to the underlying genetic subtype, and might be useful markers to monitor disease. Peripheral neuropathy is frequently observed in SCA, but subtype-specific features and subclinical manifestations have rarely been evaluated. We performed a multicenter nerve conduction study with 162 patients with genetically confirmed SCA1, SCA2, SCA3, and SCA6. The study proved peripheral nerves to be involved in the neurodegenerative process in 82 % of SCA1, 63 % of SCA2, 55 % of SCA3, and 22 % of SCA6 patients. Most patients of all subtypes revealed affection of both sensory and motor fibers. Neuropathy was most frequently of mixed type with axonal and demyelinating characteristics in all SCA subtypes. However, nerve conduction velocities of SCA1 patients were slower compared to other genotypes. SCA6 patients revealed less axonal damage than patients with other subtypes. No influence of CAG repeat length or biometric determinants on peripheral neuropathy could be identified in SCA1, SCA3, and SCA6. In SCA2, earlier onset and more severe ataxia were associated with peripheral neuropathy. We proved peripheral neuropathy to be a frequent site of the neurodegenerative process in all common SCA subtypes. Since damage to peripheral nerves is readily assessable by electrophysiological means, nerve conduction studies should be performed in a longitudinal approach to assess these parameters as potential progression markers.
['Linnemann|Christoph|C|', 'Tezenas du Montcel|Sophie|S|', 'Rakowicz|Maryla|M|', 'Schmitz-Hübsch|Tanja|T|', 'Szymanski|Sandra|S|', 'Berciano|Jose|J|', 'van de Warrenburg|Bart P|BP|', 'Pedersen|Karine|K|', 'Depondt|Chantal|C|', 'Rola|Rafal|R|', 'Klockgether|Thomas|T|', 'García|Antonio|A|', 'Mutlu|Gurkan|G|', 'Schöls|Ludger|L|']
D000293:Adolescent D000328:Adult D000368:Aged D000369:Aged, 80 and over D015220:Calcium Channels D018450:Disease Progression D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D009419:Nerve Tissue Proteins D009431:Neural Conduction D009687:Nuclear Proteins D010523:Peripheral Nervous System Diseases D020754:Spinocerebellar Ataxias D055815:Young Adult
Peripheral neuropathy Spinocerebellar ataxia Nerve conduction Electrophysiology Progression marker