title: Autoimmune epilepsy: clinical characteristics and response to immunotherapy.
abstract: OBJECTIVE
  To describe clinical characteristics and immunotherapy responses in patients with autoimmune epilepsy.
  
  
  METHODS
  Observational, retrospective case series.
  
  
  METHODS
  Mayo Clinic Health System.
  
  
  METHODS
  Thirty-two patients with an exclusive (n=11) or predominant (n=21) seizure presentation in whom an autoimmune etiology was suspected (on the basis of neural autoantibody [91%], inflammatory cerebrospinal fluid [31%], or magnetic resonance imaging suggesting inflammation [63%]) were studied. All had partial seizures: 81% had failed treatment with 2 or more antiepileptic drugs and had daily seizures and 38% had seizure semiologies that were multifocal or changed with time. Head magnetic resonance imaging was normal in 15 (47%) at onset. Electroencephalogram abnormalities included interictal epileptiform discharges in 20; electrographic seizures in 15; and focal slowing in 13. Neural autoantibodies included voltage-gated potassium channel complex in 56% (leucine-rich, glioma-inactivated 1 specific, 14; contactin-associated proteinlike 2 specific, 1); glutamic acid decarboxylase 65 in 22%; collapsin response- mediator protein 5 in 6%; and Ma2, N-methyl-D-aspartate receptor, and ganglionic acetylcholine receptor in 1 patient each.
  
  
  METHODS
  Immunotherapy with intravenous methylprednisolone; intravenous immune globulin; and combinations of intravenous methylprednisolone, intravenous immune globulin, plasmapheresis, or cyclophosphamide.
  
  
  METHODS
  Seizure frequency.
  
  
  RESULTS
  After a median interval of 17 months (range, 3-72 months), 22 of 27 (81%) reported improvement postimmunotherapy; 18 were seizure free. The median time from seizure onset to initiating immunotherapy was 4 months for responders and 22 months for nonresponders (P<.05). All voltage-gated potassium channel complex antibody-positive patients reported initial or lasting benefit (P<.05). One voltage-gated potassium channel complex antibody-positive patient was seizure free after thyroid cancer resection; another responded to antiepileptic drug change alone.
  
  
  CONCLUSIONS
  When clinical and serological clues suggest an autoimmune basis for medically intractable epilepsy, early-initiated immunotherapy may improve seizure outcome.
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, College of Medicine, Rochester, MN 55905, USA.
authors.forename: Amy M L
authors.initials: AM
authors.lastname: Quek
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Britton
authors.forename: Andrew
authors.initials: A
authors.lastname: McKeon
authors.forename: Elson
authors.initials: E
authors.lastname: So
authors.forename: Vanda A
authors.initials: VA
authors.lastname: Lennon
authors.forename: Cheolsu
authors.initials: C
authors.lastname: Shin
authors.forename: Christopher
authors.initials: C
authors.lastname: Klein
authors.forename: Robert E
authors.initials: RE
authors.lastname: Watson
authors.forename: Amy L
authors.initials: AL
authors.lastname: Kotsenas
authors.forename: Terrence D
authors.initials: TD
authors.lastname: Lagerlund
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Cascino
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Worrell
authors.forename: Elaine C
authors.initials: EC
authors.lastname: Wirrell
authors.forename: Katherine C
authors.initials: KC
authors.lastname: Nickels
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Aksamit
authors.forename: Katherine H
authors.initials: KH
authors.lastname: Noe
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Pittock
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000134:cerebrospinal fluid; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D003520:Cyclophosphamide / Q000627:therapeutic use; D004569:Electroencephalography; D004827:Epilepsy / Q000209:etiology / Q000276:immunology / Q000628:therapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007136:Immunoglobulins / Q000627:therapeutic use; D007155:Immunologic Factors / Q000627:therapeutic use; D007167:Immunotherapy / Q000379:methods*; D007249:Inflammation / Q000134:cerebrospinal fluid / Q000150:complications*; D008279:Magnetic Resonance Imaging; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000276:immunology; D010956:Plasmapheresis / Q000379:methods; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D007136:Immunoglobulins; D007155:Immunologic Factors; D009419:Nerve Tissue Proteins; D019788:Fluorodeoxyglucose F18; D003520:Cyclophosphamide; D008775:Methylprednisolone