Huntington's disease masquerading as spinocerebellar ataxia

Huntington's disease (HD) is a neurodegenerative disorder of the central nervous system characterised by the presence of choreic abnormal movements, behavioural or psychiatric disturbances and dementia. Noteworthy, despite atypical motor symptoms other than chorea have been reported as initial presentation in some patients, a very few number of HD patients, presenting at onset mostly cerebellar dysfunction masquerading dominant spinocerebellar ataxias (SCA), were occasionally reported. We report the case of a 42-year-old man with a 5-year history of gait disturbance, dysarthria and cognitive impairment and familial antecedents of dementia and movement disorders. Initially the clinical picture suggested the diagnosis of a dominant SCA, but finally a diagnosis of HD was made based on the molecular evidence of abnormal 39 Cytosine-Adenine-Guanine (CAG) repeats in exon 1 of Huntingtin gene. The authors highlight the importance of suspecting HD in the aetiology of spinocerebellar ataxias when dementia is a prominent feature in the proband or their family.