Glutamate dehydrogenase (GDH) deficiency in different types of progressive hereditary cerebellar ataxia.

Leukocyte glutamate dehydrogenase (GDH) was studied in 29 patients affected by progressive cerebellar ataxia (PCA) and in 20 healthy controls. Eight GDH-deficient patients, with GDH activity 2 SD below mean value of controls, were identified. GDH deficiency did not identify a subgroup of PCA by characteristic pattern of inheritance and/or age of onset of disease. However, the GDH-deficient patients presented more neurological signs than non-GDH-deficient patients. A significant correlation was observed between GDH deficiency and the presence of extrapyramidal signs, supranuclear palsy, absence of osteotendineal reflexes and neurogenic electromyographical findings.