title: The impact of 2015 neuromyelitis optica spectrum disorders criteria on diagnostic rates.
abstract: BACKGROUND
  The international panel for neuromyelitis optica (NMO) diagnosis has proposed diagnostic criteria for neuromyelitis optica spectrum disorders (NMOSD).
  
  
  OBJECTIVE
  We assessed the impact of these criteria on diagnostic rates in a large cohort of patients.
  
  
  METHODS
  We identified and applied the 2006 and 2015 criteria to all patients ( n = 176) seen in the NMO and non-multiple sclerosis central nervous system demyelination clinic (part of the UK NMO service) from January 2013 to May 2015.
  
  
  RESULTS
  The 2006 criteria classified 63 of 176 (36%) patients as NMO. A total of 42 patients (67%) were aquaporin 4 (AQP4) immunoglobulin G (IgG) +ve and 21 (33%) AQP4 IgG -ve. The 2015 criteria classified 111 of 176 (63%) patients as NMOSD, of which 81 (73%) were AQP4 IgG +ve and 30 (27%) were AQP4 IgG -ve. There was an increase of 48 patients (76%) diagnosed as NMOSD using the new criteria.
  
  
  CONCLUSIONS
  Application of the 2015 criteria led to a rise in diagnosis of NMOSD by 76%. The rise in the AQP4 IgG +ve group contributed 62% and the seronegative group contributed 14%.
authors.affiliation: The Walton Centre, NHS Foundation Trust, Liverpool, UK.
authors.forename: Shahd Hm
authors.initials: SH
authors.lastname: Hamid
authors.affiliation: The Walton Centre, NHS Foundation Trust, Liverpool, UK.
authors.forename: Liene
authors.initials: L
authors.lastname: Elsone
authors.affiliation: The Walton Centre, NHS Foundation Trust, Liverpool, UK.
authors.forename: Kerry
authors.initials: K
authors.lastname: Mutch
authors.affiliation: Institute of Infectious Disease and Global Health, University of Liverpool, Liverpool, UK/The Walton Centre, NHS Foundation Trust, Liverpool, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Solomon
authors.affiliation: The Walton Centre, NHS Foundation Trust, Liverpool, UK.
authors.forename: Anu
authors.initials: A
authors.lastname: Jacob
mesh_terms: D051401:Aquaporin 4 / Q000378:metabolism; D001323:Autoantibodies / Q000378:metabolism*; D002490:Central Nervous System / Q000276:immunology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D008297:Male; D009471:Neuromyelitis Optica / Q000175:diagnosis*
chemical_list: C496030:AQP4 protein, human; D051401:Aquaporin 4; D001323:Autoantibodies; D007074:Immunoglobulin G
keywords: Neuromyelitis optica spectrum disorders; central nervous system demyelination; criteria; multiple sclerosis