title: Paediatric neuromyelitis optica: clinical, MRI of the brain and prognostic features.
abstract: BACKGROUND
  Neuromyelitis Optica (NMO) is a severe and rare inflammatory condition, where relapses are predictive of disability.
  
  
  METHODS
  We describe a national paediatric NMO cohort's clinical, MRI, outcome, and prognostic features in relation to Aquaporin-4 antibody (AQP4-Ab) status, and compared to a non NMO control cohort.
  
  
  METHODS
  Twenty NMO cases (females = 90%; AQP4-Ab positive = 60%; median age = 10.5 yrs) with median follow-up = 6.1 yrs were compared to a national cohort sample of known sequential AQP4-Ab negative first episode CNS acquired demyelination cases (n = 29; females = 55%; all AQP4-Ab negative; median age = 13.6 yrs). At presentation, 40% NMO cases had unilateral optic neuritis (ON); 20% bilateral ON; 15% transverse myelitis (TM); 15% simultaneous TM&ON; 10% Acute disseminated encephalomyelitis. At follow up, 55% had a clinical demyelinating episode involving the brain; 30% of cases had abnormal brain MRI at onset and 75% by follow up. NMO brain scan lesions compared to controls were large (> 2 cm), acute lesions largely resolved on repeat imaging, and often showed T1 hypointense lesions. Mean time to relapse = 0.76 yrs (95% CI 0.43-1.1 yrs) for AQP4-Ab positive vs 2.4 yrs in AQP4-Ab negative cases (95% CI 1.1-3.6 yrs). In AQP4-Ab positive cases, 10/12 had visual acuity < 6/60 Snellen in ≥ 1 eye (0/8 AQP4-Ab negative), and 3 AQP4-Ab negative cases were wheelchair-dependent.
  
  
  CONCLUSIONS
  In children, NMO is associated with early recurrence and visual impairment in AQP4-Ab positivity and physical disability in AP4-Ab negative relapsing cases. Distinct MRI changes appear more commonly and earlier compared to adult NMO. Early AQP4-Ab testing may allow prompt immunomodulatory treatment to minimise disability.
authors.affiliation: Department of Children's Neurosciences, Evelina Children's Hospital at Guy's & St Thomas' NHS Foundation Trust, Kings Health Partners Academic Health Science Centre, London, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Absoud
authors.affiliation: Department of Children's Neurosciences, Evelina Children's Hospital at Guy's & St Thomas' NHS Foundation Trust, Kings Health Partners Academic Health Science Centre, London, UK.
authors.forename: Ming J
authors.identifier: http://orcid.org/0000-0001-7738-8910
authors.initials: MJ
authors.lastname: Lim
authors.affiliation: The Roald Dahl EEG Unit, Pediatric Neurosciences Foundation, Alder Hey Children's Hospital, Liverpool, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Appleton
authors.affiliation: Department of Neurology, The Walton Centre for Neurology and Neurosurgery, Liverpool, North Lincolnshire, UK.
authors.forename: Anu
authors.initials: A
authors.lastname: Jacob
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: Joanna
authors.initials: J
authors.lastname: Kitley
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: M Isabel
authors.identifier: http://orcid.org/0000-0003-4407-5066
authors.initials: MI
authors.lastname: Leite
authors.affiliation: Department of Neurology, Oxford Children's Hospital, Oxford University Hospitals National Health Service Trust, Oxford, UK.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Pike
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: Angela
authors.initials: A
authors.lastname: Vincent
authors.affiliation: Department of Neurology, Birmingham Children's Hospital, Birmingham, UK.
authors.forename: Evangeline
authors.initials: E
authors.lastname: Wassmer
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: Patrick
authors.initials: P
authors.lastname: Waters
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Woodhall
authors.affiliation: Department of Neurology, Great Ormond Street Hospital for Children, London, UK.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Hemingway
authors.affiliation: Nuffield Department of Clinical Neurosciences, Oxford University Hospitals National Health Service Trust, University of Oxford, Oxford, UK.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Palace
mesh_terms: D000293:Adolescent; D000906:Antibodies / Q000032:analysis; D051401:Aquaporin 4 / Q000276:immunology; D001921:Brain / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009471:Neuromyelitis Optica / Q000473:pathology*; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000906:Antibodies; D051401:Aquaporin 4
keywords: EPIDEMIOLOGY; MRI; MULTIPLE SCLEROSIS; NEUROIMMUNOLOGY; PAEDIATRIC