title: Suspected antibody negative autoimmune limbic encephalitis: outcome of immunotherapy.
abstract: OBJECTIVE
  Whether and when to immunologically treat epilepsy patients with suggested autoantibody (AB)-negative limbic encephalitis (LE) is clinically challenging. Therefore, we evaluated the clinical outcome and eventual outcome predictors of immunotherapy in a group of AB-negative patients with recent-onset temporal lobe epilepsy (TLE), magnetic resonance imaging (MRI) indicators of LE, subjective cognitive decline, and/or psychiatric symptoms.
  
  
  METHODS
  This retrospective, observational, uncontrolled study monitored 28 TLE patients with suggested AB-negative LE along with methylprednisolone immunotherapy.
  
  
  RESULTS
  All patients had seizures, amygdala and/or -hippocampal enlargement, subjective cognitive decline and/or behavioral problems. Eighty-six percent (24/28) were impaired in executive or memory functions, 39% (10/25) depressed, 81% were on antiepileptic drugs when pulse therapy started. After a median follow-up of 18 months, 46% (13/28) of the patients were seizure free (>2 months), 48% (13/27) showed MRI improvements (amygdala and/or hippocampal volume reduction), cognition improved in 57% (16/28), worsened in 32% (9/28), mood improved in 14% (4/25), and deteriorated in 11% (3/25). Immunotherapy was discontinued in 75% (21/28). Clinical changes did not correlate to each other. Outcomes could not be predicted.
  
  
  CONCLUSIONS
  Immunological treatment of suggested AB-negative LE showed reasonable seizure control, MRI and cognitive improvements. Treatment success was not predictable from clinical features, nor definitely attributable to immunological treatment. Lacking biomarkers for the reliable diagnosis of AB-negative LE, we suggest that in presence of mild manifestations, and after initiating antiepileptic drug therapy, negative dynamics in MRI, seizures, cognition, and behavior should be documented before immunosuppressive treatment is initiated.
authors.affiliation: Department of Epileptology, University of Bonn Medical Centre, Bonn, Germany.
authors.forename: B
authors.initials: B
authors.lastname: von Rhein
authors.affiliation: Department of Epileptology, University of Bonn Medical Centre, Bonn, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Wagner
authors.affiliation: Department of Epileptology, University of Bonn Medical Centre, Bonn, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Widman
authors.affiliation: Department of Neurology, University Hospital Cologne, Cologne, Germany.
authors.forename: M P
authors.initials: MP
authors.lastname: Malter
authors.affiliation: Department of Epileptology, University of Bonn Medical Centre, Bonn, Germany.
authors.forename: C E
authors.initials: CE
authors.lastname: Elger
authors.affiliation: Department of Epileptology, University of Bonn Medical Centre, Bonn, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Helmstaedter
mesh_terms: D000328:Adult; D000339:Affect; D000679:Amygdala / Q000000981:diagnostic imaging; D001327:Autoimmune Diseases / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D003071:Cognition; D004833:Epilepsy, Temporal Lobe / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging; D006801:Humans; D007116:Immunization, Passive / Q000009:adverse effects*; D020363:Limbic Encephalitis / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D008875:Middle Aged
keywords: antiepileptic drugs; epilepsy; immunology; mild cognitive impairment; treatment