title: Nodding syndrome in Tanzania may not be associated with circulating anti-NMDA-and anti-VGKC receptor antibodies or decreased pyridoxal phosphate serum levels-a pilot study.
abstract: BACKGROUND
  Nodding syndrome (NS) is a seemingly progressive epilepsy disorder of unknown underlying cause. We investigated association of pyridoxal-phosphate serum levels and occurrence of anti-neuronal antibodies against N-methyl-D-aspartate (NMDA) receptor and voltage gated potassium channel (VGKC) complex in NS patients.
  
  
  METHODS
  Sera of a Tanzanian cohort of epilepsy and NS patients and community controls were tested for the presence of anti-NMDA-receptor and anti-VGKC complex antibodies by indirect immunofluorescence assay. Furthermore pyridoxal-phosphate levels were measured.
  
  
  RESULTS
  Auto-antibodies against NMDA receptor or VGKC (LG1 or Caspr2) complex were not detected in sera of patients suffering from NS (n=6), NS plus other seizure types (n=16), primary generalized epilepsy (n=1) and community controls without epilepsy (n=7). Median Pyridoxal-phosphate levels in patients with NS compared to patients with primary generalized seizures and community controls were not significantly different. However, these median pyridoxal-phosphate levels are significantly lower compared to the range considered normal in Europeans.
  
  
  CONCLUSIONS
  In this pilot study NS was not associated with serum anti-NMDA receptor or anti-VGKC complex antibodies and no association to pyridoxal-phosphate serum levels was found.
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Anelia
authors.initials: A
authors.lastname: Dietmann
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Bernd
authors.initials: B
authors.lastname: Wallner
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Rebekka
authors.initials: R
authors.lastname: König
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Katrin
authors.initials: K
authors.lastname: Friedrich
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Bettina
authors.initials: B
authors.lastname: Pfausler
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Deisenhammer
authors.affiliation: Central Institute of Medical and Chemical Laboratory Diagnostics, Medical University Innsbruck, Austria.
authors.forename: Andrea
authors.initials: A
authors.lastname: Griesmacher
authors.affiliation: Central Institute of Medical and Chemical Laboratory Diagnostics, Medical University Innsbruck, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Seger
authors.affiliation: Division of Neurology, Muhimbili Medical Centre, Dar es Salaam, Tanzania.
authors.forename: William
authors.initials: W
authors.lastname: Matuja
authors.affiliation: Department of Psychiatry, University of British Columbia, Vancouver, Canada.
authors.forename: Louise
authors.initials: L
authors.lastname: JilekAall
authors.affiliation: Department of Neurology, Technical University Munich, Germany.
authors.forename: Andrea S
authors.initials: AS
authors.lastname: Winkler
authors.affiliation: Department of Neurology, Medical University Innsbruck, Austria.
authors.forename: Erich
authors.initials: E
authors.lastname: Schmutzhard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D016022:Case-Control Studies; D004827:Epilepsy / Q000097:blood* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016202:N-Methylaspartate / Q000097:blood / Q000276:immunology*; D009474:Neurons / Q000276:immunology; D064128:Nodding Syndrome; D010865:Pilot Projects; D024642:Potassium Channels, Voltage-Gated / Q000097:blood / Q000276:immunology*; D011732:Pyridoxal Phosphate / Q000097:blood*; D012640:Seizures / Q000097:blood* / Q000276:immunology; D013636:Tanzania
chemical_list: D001323:Autoantibodies; D024642:Potassium Channels, Voltage-Gated; D011732:Pyridoxal Phosphate; D016202:N-Methylaspartate
keywords: anti-neuronal antibodies; epilepsy; nodding syndrome; pyridoxal-phosphate