title: Deep white matter pathologic features in watershed regions: a novel pattern of central nervous system involvement in MELAS.
abstract: BACKGROUND
  Myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome typically manifests in adults younger than 40 years with encephalopathy, stroke-like episodes, and lactic acidosis. Magnetic resonance imaging (MRI) abnormalities typically involve the cortical gray and the adjacent subcortical white matter.
  
  
  OBJECTIVE
  To describe a 58-year-old woman diagnosed with MELAS who was initially seen with acute myopathy, cardiac ischemia, psychosis, and MRI changes in a watershed distribution.
  
  
  RESULTS
  Initial MRI of the brain showed the characteristic parieto-occipital gray matter lesions involving the adjacent white matter. Follow-up MRI revealed striking deep white matter involvement in a watershed distribution. A cerebral angiogram and thorough hypercoagulable workup results were normal. Electromyography showed acute denervation and myopathy. A muscle biopsy specimen revealed ragged red and cytochrome-c oxidase-negative fibers. Mitochondrial DNA analysis revealed an A3243G mutation.
  
  
  CONCLUSIONS
  Myopathy, encephalopathy, lactic acidosis, and stroke-like episodes should be considered in older patients with myopathy, cardiomyopathy, encephalopathy, and unaccountable MRI findings. Watershed pathologic features are a rare pattern of cerebral involvement in MELAS.
authors: Department of Neurology, University of California, Los Angeles, USA. lapostolova@mednet.ucla.edu
authors: Liana G
authors: LG
authors: Apostolova
authors: Matthew
authors: M
authors: White
authors: Steven A
authors: SA
authors: Moore
authors: Patricia H
authors: PH
authors: Davis
mesh_terms: D000208:Acute Disease; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D006801:Humans; D017241:MELAS Syndrome / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009135:Muscular Diseases / Q000209:etiology; D017202:Myocardial Ischemia / Q000209:etiology; D011618:Psychotic Disorders / Q000209:etiology; D020521:Stroke / Q000209:etiology