title: Peripheral neuropathy in genetic mitochondrial diseases.
abstract: Peripheral neuropathy is an underrecognized but common occurrence in genetic mitochondrial disorders. To gain insight into the frequency and clinical presentation of this complication, nerve conduction studies were performed on 43 subjects with congenital lactic acidosis enrolled in a controlled clinical trial of oral dichloroacetate. Median and peroneal motor conduction studies and median and sural sensory conduction studies were performed on each patient. The mean amplitude of the peroneal motor nerve (P < 0.001) and the conduction velocities of the median (P < 0.001) and peroneal (P < 0.001) motor nerves were uniformly lower in our subjects than in healthy literature control subjects. There were no significant differences in sensory nerve conduction studies. A generalized reduction in motor nerve conduction velocity was the dominant electrophysiological abnormality in the patients in this study and was independent of age, sex, or congenital mitochondrial disorder. We postulate that cellular energy failure is the most likely common cause of peripheral neuropathy in patients with genetic mitochondrial diseases, owing to the high demand for adenosine triphosphate via aerobic carbohydrate metabolism by nerve tissue.
authors.affiliation: Department of Neurology, University of Florida, Gainesville, Florida, USA. stickle@musc.edu
authors.forename: David E
authors.initials: DE
authors.lastname: Stickler
authors.forename: Edward
authors.initials: E
authors.lastname: Valenstein
authors.forename: Richard E
authors.initials: RE
authors.lastname: Neiberger
authors.forename: Leigh Ann
authors.initials: LA
authors.lastname: Perkins
authors.forename: Paul R
authors.initials: PR
authors.lastname: Carney
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Shuster
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Theriaque
authors.forename: Peter W
authors.initials: PW
authors.lastname: Stacpoole
mesh_terms: D000140:Acidosis, Lactic / Q000150:complications / Q000503:physiopathology*; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008475:Median Nerve / Q000503:physiopathology*; D028361:Mitochondrial Diseases / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D009431:Neural Conduction / Q000502:physiology*; D010523:Peripheral Nervous System Diseases / Q000209:etiology; D010543:Peroneal Nerve / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology; D013497:Sural Nerve / Q000503:physiopathology*