title: Axonal degeneration in peripheral nerves in a case of Leber hereditary optic neuropathy.
abstract: BACKGROUND
  Leber hereditary optic neuropathy (LHON) is a mitochondrial DNA (mtDNA) genetic disorder characterized by profound bilateral loss of central vision due to selective loss of retinal ganglion cells. Most patients with LHON do not have complaints related to the peripheral nervous system. We investigated possible qualitative and quantitative histological changes in the peripheral nerve of a patient with LHON as compared to normal controls.
  
  
  METHODS
  Brachial plexus specimens were obtained at necropsy from a patient with LHON carrying the 3460/ND1 mtDNA mutation and age-matched controls without known history of neurological disease. The nerves were evaluated by light microscope coupled to a digital camera-based morphometric analysis and electron microscopy.
  
  
  RESULTS
  Extensive axonal degeneration of the large heavily myelinated fibers was found in the brachial plexus from the patient with LHON. In LHON nerve fascicles, we counted over 10 times as many degenerated profiles as found in the control nerve fascicles.
  
  
  CONCLUSIONS
  Microscopic examination of the brachial plexus in the patient with LHON clearly demonstrated a significant pattern of neurodegeneration. Our study suggests that peripheral neuropathy may be a subclinical feature associated with LHON.
authors.affiliation: Doheny Eye Institute, Department of Ophthalmology, University of Southern California, Los Angeles, California 90033, USA.
authors.forename: Lilit
authors.initials: L
authors.lastname: Mnatsakanyan
authors.forename: Fred N
authors.initials: FN
authors.lastname: Ross-Cisneros
authors.forename: Valerio
authors.initials: V
authors.lastname: Carelli
authors.forename: Michelle Y
authors.initials: MY
authors.lastname: Wang
authors.forename: Alfredo A
authors.initials: AA
authors.lastname: Sadun
mesh_terms: D000368:Aged; D020516:Brachial Plexus Neuropathies / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D029242:Optic Atrophy, Hereditary, Leber / Q000150:complications* / Q000235:genetics* / Q000503:physiopathology; D010523:Peripheral Nervous System Diseases / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D014855:Wallerian Degeneration / Q000235:genetics / Q000473:pathology / Q000503:physiopathology