Sporadic Degenerative Ataxia With Adult Onset: Natural History Study

Inclusion Criteria: * Progressive ataxia * Disease onset after the age of 40 years * Informative and negative family history (no similar disorders in first- and second-degree relatives; parents older than 50 years, or, if not alive, age at death of more than 50 years, no consanguinity of parents) Exclusion Criteria: * No established acquired cause of ataxia Clinical exclusion criteria: * No onset of ataxia in association with stroke, encephalitis, sepsis, hyperthermia or heat stroke; * no chronic diarrhea; * no unexplained visual loss; * no alcohol abuse; * no chronic intake of anticonvulsant drugs; * no other toxic causes; no malignancies; * no rapid progression (development of severe ataxia in less than 12 weeks); * no insulin-dependent diabetes mellitus Imaging exclusion criteria: * No evidence of multiple sclerosis, ischemia, hemorrhage or tumor of the posterior fossa; * absence of signal abnormalities on T2/FLAIR-images except abnormalities compatible with MSA Laboratory exclusion criteria: * Negative molecular genetic testing for FRDA (only required if there is no cerebellar atrophy on MRI, SCA1, SCA2, SCA3, SCA6, FMR1 premutation (only required if prominent tremor, cognitive impairment and signal abnormality on T2/FLAIR images in the middle cerebellar peduncle); * antineuronal antibodies negative (only required, if disease duration less than 3 years); * normal levels of vitamin B12; * VDRL negative; * normal thyreoid function