Clinical and biochemical studies in Friedreich's disease

In the first part of this study we report data concerning the natural history of Friedreich's disease (FD) which show that: 1. clinical signs of peripheral neuropathy are very early and constant, and ataxic features are relatively tardive and show a steady progression; 2. decrease of large myelinated fibers probably occurs early in life following axonal atrophy; 3. brainstem auditory evoked responses are severely affected and their disappearance is related to severity of the illness. The second part concerns biochemical data on the distribution of mitochondrial malic enzyme (ME(m)) and glutamic dehydrogenase (GDH) in normal brain. Enzyme activity varied greatly in the various regions studied and critical levels were detected in regions that are electively involved in ataxic syndromes.