SCA1 patients may present as hereditary spastic paraplegia and must be included in spastic-ataxias group

Abstract

Introduction: The combination of cerebellar ataxia and spasticity is common. However, autosomal dominant genetic diseases presenting with spastic-ataxia are a smaller group. Pyramidal signs have been frequently observed in several SCA subtypes, particularly in spinocerebellar ataxia type 1.

Methods: We prospectively evaluated the pyramidal signs and spasticity in SCA1 patients, and correlated the data with genetic and clinical features.

Results: In this study, we observed that spasticity may be an early and presenting feature of SCA1, since 3 patients had pyramidal signs and spasticity as the first neurological sign. SCA1 patients with spasticity were significantly younger.

Conclusion: SCA1 may rarely present with pure spastic paraplegia, resembling hereditary spastic paraplegia, before the appearance of cerebellar signs. This observation may confuse the neurologist when a genetic testing is requested for an autosomal dominant spastic paraplegia, directing research to hereditary spastic paraplegia group.

Keywords: Pyramidal signs; SCA; SCA1; Spasticity; Spinocerebellar ataxia type 1.