title: VGKC complex antibodies in epilepsy: diagnostic yield and therapeutic implications.
abstract: OBJECTIVE
  In a significant number of patients developing epilepsy in adult life, the aetiology of their seizures remains unclear. Antibodies directed against the voltage gated potassium channel complex (VGKC Ab) have been identified in various cohorts of patients with epilepsy, although the role of these antibodies in epilepsy pathogenesis is not fully known.
  
  
  METHODS
  We reviewed the notes of 144 patients with unexplained adult onset epilepsy who had been tested for VGKC Abs. We collected data on their clinical syndrome, investigation results and response to treatment.
  
  
  RESULTS
  We identified 6 (4.2%) patients who had titres of >400 pM. One of the six patients was positive for LGI1 and another for CASPR2 subunit antibodies. All patients were given immunotherapy and experienced improvement in seizure control. No patient had the clinical syndrome of limbic encephalitis.
  
  
  CONCLUSIONS
  Patients with otherwise unexplained epilepsy and positive VGKC Abs are a heterogeneous group. In our cohort there was an overall favourable response to immunotherapy but further prospective studies are needed to determine the significance of these antibodies and the optimum treatment regimen for patients.
authors.affiliation: Department of Neurology, Greater Manchester Neurosciences Centre, Salford Royal Hospital, United Kingdom.
authors.forename: James B
authors.initials: JB
authors.lastname: Lilleker
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Jones
authors.forename: Rajiv
authors.initials: R
authors.lastname: Mohanraj
mesh_terms: D000328:Adult; D000368:Aged; D000906:Antibodies / Q000097:blood*; D015331:Cohort Studies; D004827:Epilepsy / Q000097:blood / Q000276:immunology* / Q000628:therapy; D005260:Female; D006801:Humans; D007167:Immunotherapy; D047908:Intracellular Signaling Peptides and Proteins; D008279:Magnetic Resonance Imaging; D008297:Male; D008565:Membrane Proteins / Q000276:immunology; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000276:immunology; D024642:Potassium Channels, Voltage-Gated / Q000276:immunology*; D011506:Proteins / Q000276:immunology; D013997:Time Factors
chemical_list: D000906:Antibodies; C403049:CNTNAP2 protein, human; D047908:Intracellular Signaling Peptides and Proteins; C116499:LGI1 protein, human; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D024642:Potassium Channels, Voltage-Gated; D011506:Proteins
keywords: Autoimmune epilepsy; Immunotherapy; Potassium channel antibody; VGKC