title: Diagnostic Utility of Systematic Aquaporin-4 Antibodies Determination in the First Event of Immune-Mediated Optic Neuritis.
abstract: Antibodies against aquaporin-4 (AQP4-ab) have diagnostic and prognostic value. However, little is known to date about their utility in the first event of optic neuritis (ON).
  
  
  
  To evaluate the utility of systematic AQP4-ab determination in a retrospective cohort of patients with a first onset of ON.
  
  
  
  All patients (n = 42) were tested for AQP4-ab in the following context: typical ON (TON) and atypical ON (AON). Clinical, radiological and biochemical data were collected; patients with TON vs. AON and AQP4-ab positive vs. negative were compared.
  
  
  
  The proportion of AQP4-ab seropositive patients was 40% in the TON group vs. 40.9% in the AON group. Visual acuity (VA) at baseline was poor in AON patients (p = 0.02) and these patients were associated with worse VA outcome (p < 0.001) at 6 months compared with TON patients, with a median follow-up of 3.27 ± 1.79 years. Brain MRI with dissemination in space criteria (p < 0.001), spinal cord partial lesions (p < 0.001) and oligoclonal bands (p = 0.02) were associated with the initial stages of TON. VA severity, number of myelitis attacks and ON relapses did not differ significantly between seropositive and seronegative patients. AQP4-ab were detected only in neuromyelitis optica spectrum disorders patients.
  
  
  
  This study showed a high seropositivity for AQP4-ab in TON patients, suggesting that it could diagnostic utility at the onset of ON.
authors.affiliation: Department of Neurology, University of Buenos Aires, Hospital Carlos G. Durand, Buenos Aires, Argentina.
authors.forename: Edgar
authors.initials: E
authors.lastname: Carnero Contentti
authors.forename: Mariana
authors.initials: M
authors.lastname: De Virgiliis
authors.forename: Javier Pablo
authors.initials: JP
authors.lastname: Hryb
authors.forename: Felisa
authors.initials: F
authors.lastname: Leguizamon
authors.forename: Julia
authors.initials: J
authors.lastname: Celso
authors.forename: José Luis
authors.initials: JL
authors.lastname: Di Pace
authors.forename: Mónica
authors.initials: M
authors.lastname: Perassolo
mesh_terms: D000328:Adult; D051401:Aquaporin 4 / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000276:immunology; D001921:Brain / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D043025:Oligoclonal Bands; D012189:Retrospective Studies; D013116:Spinal Cord / Q000473:pathology
chemical_list: D051401:Aquaporin 4; D001323:Autoantibodies; D001324:Autoantigens; D043025:Oligoclonal Bands