Familial idiopathic strio-pallido-dentate calcifications with late onset extrapyramidal syndrome.

A family with autosomal dominant inheritance of idiopathic strio-pallidodentate calcifications and late onset of extrapyramidal symptoms is reported. Clinical features consisted of parkinsonism in one member and postural tremor in two. Depression and dysarthria were present in all cases. All symptomatic members showed a peculiar biochemical abnormality consisting of reduced 25-OH vitamin D3 with normal levels of 1,25(OH)2 vitamin D3, suggesting an inborn error of Vitamin D metabolism. The biochemical, clinical, and genetic pattern of this family distinguishes this syndrome from the larger group of secondary familial basal ganglia calcifications.