[A case of spinocerebellar ataxia type 2 presenting with a clinical course similar to spastic paraparesis].

We report a 50-year-old woman with an unremarkable birth and developmental history, and with no family history of neurological disorders. The patient had a 6-year history of progressive cervical dystonia, oral dyskinesia, and hyperreflexia. She was initially considered to have spastic paraparesis of unknown cause. Because brain MRI showed mild atrophy of the cerebellar vermis, genetic analysis for spinocerebellar ataxia types 1, 2, 3, 6, 7, 8, 12, and 17, and dentatorubral-pallidoluysian atrophy was performed. The results revealed an abnormal expansion of CAG repeats (38 repeats) in one allele of ATXN2, and the patient was diagnosed with spinocerebellar ataxia type 2 (SCA2). She had no major clinical features of SCA2 such as cerebellar ataxia, slow saccade, or hyporeflexia. Recent reports have shown the CAG repeat expansion in ATXN2 to be detected in patients with familial L-dopa-responsive parkinsonism. The present case suggests that CAG repeat expansion in ATXN2 may be detected in some patients with spastic paraparesis, and that wide variations of clinical manifestations exist in SCA2.