Atypical parkinsonism and cerebrotendinous xanthomatosis: report of a family with corticobasal syndrome and a literature review.

Cerebrotendinous xanthomatosis is an autosomal recessive inborn error of cholesterol metabolism. It presents with systemic and neurological symptoms, rarely including parkinsonism. Presented here are a clinical description of a new family with cerebrotendinous xanthomatosis and parkinsonism and a review of 13 additional cases reported in the literature. The index case developed corticobasal syndrome, previously not reported in cerebrotendinous xanthomatosis. His brother had parkinsonism with cerebellar features and cognitive impairment. In a literature review, median age of onset of parkinsonism was found to be 40 years. Nearly all patients had other neurological symptoms: cognitive (93%), pyramidal (93%), or cerebellar (53%). All patients had walking difficulties, with falls in 27%. Systemic features were common: cataracts (93%) or tendon xanthomata (87%). Frequent MRI abnormalities included cerebellar atrophy (100%), cerebral atrophy (80%), and dentate nuclei signal changes (80%). Functional dopaminergic imaging often demonstrated presynaptic denervation. Improvement with levodopa was frequent (91%) but mild. Progressive neurological decline occurred in 92% of patients despite treatment with chenodeoxycholic acid. Cerebrotendinous xanthomatosis should be considered in the differential diagnosis of atypical parkinsonism, including corticobasal syndrome, particularly with early age of onset and in the context of a complex neurological phenotype. Tendon xanthomata, early-onset cataracts, and radiological findings of cerebellar atrophy with lesions of the dentate nuclei are useful clinical clues. Symptomatic treatment with levodopa may help, but progressive neurological decline is frequent despite treatment with chenodeoxycholic acid.