Spectrum of movement disorders associated with glutaric aciduria type 1: a study of 16 patients.

Glutaric aciduria type 1 (GA1) is an autosomal recessive neurometabolic disorder due to glutaryl CoA dehydrogenase deficiency. Comprehensive descriptions of GA1-associated movement disorders are rare. In order to refine the description of the motor phenotype, we prospectively studied 16 consecutive pediatric and adult GA1 patients, focusing on the movement disorders and their time course. In most patients, generalized dystonia, superimposed on baseline axial hypotonia, remained the predominant feature throughout the disease course. With aging, it tended to evolve from mobile to fixed dystonia and to be associated with akinetic-rigid parkinsonism. Prominent orofacial involvement was a consistent feature in GA1 patients with movement disorders, resulting in speech disorders with features of combined hyperkinetic dysarthria and speech apraxia. The types and outcome of movement disorders in this setting should be taken into consideration during rehabilitation and for patient selection and evaluation in therapeutic trials.