title: Utility of Neurodiagnostic Studies in the Diagnosis of Autoimmune Encephalitis in Children.
abstract: BACKGROUND
  Autoimmune encephalitis is currently a clinical diagnosis without widely accepted diagnostic criteria, often leading to a delay in diagnosis. The utility of magnetic resonance imaging (MRI) and electroencephalography (EEG) in this disease is unknown. The objective of this study was to identify disease-specific patterns of neurodiagnostic studies (MRI and EEG) for autoimmune encephalitis in children.
  
  
  METHODS
  We completed a retrospective chart review of encephalopathic patients seen at a large pediatric hospital over a four year interval. Clinical presentation, autoantibody status, and MRI and EEG findings were identified and compared. Individuals with autoantibodies were considered "definite" cases, whereas those without antibodies or those with only thyroperoxidase antibodies were characterized as "suspected."
  
  
  RESULTS
  Eighteen patients met the inclusion criteria and autoantibodies were identified in nine of these. The patients with definite autoimmune encephalitis had MRI abnormalities within limbic structures, most notably the anteromedial temporal lobes (56%). Only individuals with suspected disease had nontemporal lobe cortical lesions. Sixteen patients had an EEG and 13 (81%) of these were abnormal. The most common findings were abnormal background rhythm (63%), generalized slowing (50%), focal slowing (43%), and focal epileptiform discharges (31%). Sleep spindle abnormalities occurred in 38% of patients. There were no specific differences in the EEG findings between the definite and suspected cases. Focal EEG findings only correlated with a focal lesion on MRI in a single definite case.
  
  
  CONCLUSIONS
  Pediatric patients with definite autoimmune encephalitis have a narrow spectrum of MRI abnormalities. Conversely, EEG abnormalities are mostly nonspecific. All patients in our cohort had abnormalities on one or both of these neurodiagnostic studies.
authors.affiliation: Section of Child Neurology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio; College of Medicine, The Ohio State University, Columbus, Ohio.
authors.forename: Dara V
authors.initials: DV
authors.lastname: Albert
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio; Department of Radiology, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Pluto
authors.affiliation: Section of Child Neurology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Amanda
authors.initials: A
authors.lastname: Weber
authors.affiliation: Section of Child Neurology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio; College of Medicine, The Ohio State University, Columbus, Ohio.
authors.forename: Jorge
authors.initials: J
authors.lastname: Vidaurre
authors.affiliation: Section of Rheumatology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Fatima
authors.initials: F
authors.lastname: Barbar-Smiley
authors.affiliation: Section of Rheumatology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Rabheh
authors.initials: R
authors.lastname: Abdul Aziz
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio; Section of Rheumatology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Kyla
authors.initials: K
authors.lastname: Driest
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio; Section of Rheumatology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Sharon
authors.initials: S
authors.lastname: Bout-Tabaku
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio; Department of Radiology, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Lynne
authors.initials: L
authors.lastname: Ruess
authors.affiliation: College of Medicine, The Ohio State University, Columbus, Ohio; Department of Radiology, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Jerome A
authors.initials: JA
authors.lastname: Rusin
authors.affiliation: Section of Child Neurology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio; College of Medicine, The Ohio State University, Columbus, Ohio. Electronic address: Bethanie.morgan@nationwidechildrens.org.
authors.forename: Bethanie
authors.initials: B
authors.lastname: Morgan-Followell
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood; D001327:Autoimmune Diseases / Q000097:blood / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography / Q000379:methods*; D004660:Encephalitis / Q000097:blood / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012189:Retrospective Studies
chemical_list: D001323:Autoantibodies
keywords: GAD65 antibody; NMDA antibody; TPO antibody; autoimmune encephalitis; electroencephalogram (EEG); magnetic resonance imaging (MRI)