title: Hypoxic-ischemic encephalopathy mimicking acute necrotizing encephalopathy.
abstract: BACKGROUND
  Acute necrotizing encephalopathy is a rare childhood syndrome associated with distinct and unifying neuroimaging features that are often used for the diagnosis of this entity.
  
  
  METHODS
  We describe a previously healthy 9-month-old girl who presented with upper respiratory symptoms, suspected seizures, and positive nasopharyngeal rapid antigen test for influenza A virus. Magnetic resonance imaging revealed signal abnormality in both thalami, bilateral caudate nuclei, brainstem tegmentum, subcortical white matter, and cerebellar hemispheres, suggestive of acute necrotizing encephalopathy. She subsequently had a cardiac arrest, was placed on extracorporeal membrane oxygenation, and treated with methylprednisone, intravenous immunoglobulin, and plasmapheresis without apparent clinical response. On autopsy, neuropathology showed evidence of hypoxic-ischemic injury but lacked evidence of hemorrhagic necrosis, which is typically associated with acute necrotizing encephalopathy.
  
  
  CONCLUSIONS
  Combined clinical and neuroimaging features may be suggestive but not sufficient for the diagnosis of acute necrotizing encephalopathy.
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Kevin Y
authors.initials: KY
authors.lastname: Wang
authors.affiliation: Department of Pediatric Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Harvey S
authors.initials: HS
authors.lastname: Singer
authors.affiliation: Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Crain
authors.affiliation: Division of Neuroradiology, Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Sachin
authors.initials: S
authors.lastname: Gujar
authors.affiliation: Division of Neuroradiology, Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: ddmlin@jhmi.edu.
authors.forename: Doris D M
authors.initials: DD
authors.lastname: Lin
mesh_terms: D001921:Brain / Q000473:pathology; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy; D007223:Infant; D004684:Leukoencephalitis, Acute Hemorrhagic / Q000175:diagnosis; D008279:Magnetic Resonance Imaging
keywords: acute necrotizing encephalopathy; hypoxic-ischemic encephalopathy; influenza; pediatric