title: [Young-onset multiple sclerosis].
abstract: BACKGROUND
  Young onset multiple sclerosis is an infrequent situation which may present with atypical symptoms and uncertain outcome.
  
  
  OBJECTIVE
  Our aim was to assess the clinical presentation and course in young onset multiple sclerosis, and analyze eventual data which might be helpful in establishing its prognosis.
  
  
  METHODS
  We have retrospectively reviewed the clinical protocols of 17 patients with young onset multiple sclerosis, defined as presentation of symptoms before 21 years. Diagnosis was made according to Poser's criteria including clinical features, magnetic resonance imaging, cerebrospinal fluid findings, and evoked potentials.
  
  
  RESULTS
  The mean age at onset was 16.9 +/- 4.4 and median time to diagnosis was four weeks. The clinical course was relapsing-remitting in 76.5% and secondary progressive in 23.5%. The mean annual exacerbation rate was 1.5 +/- 0.9 and median time to second exacerbation was 12 months. The actual Expanded Disability Status Scale score is 2.6 +/- 2 after a mean disease duration of 11.4 +/- 8.0 years. The correlation between the Expanded Disability Status Scale score and the mean disease duration was the only statistically significant result.
  
  
  CONCLUSIONS
  These results are similar to other studies, namely, age at onset did not correlate with final neurological disability. However, we must emphasize that any primary progressive form was found in our study. We conclude that in young onset multiple sclerosis, progression is not dependent on the age of onset and does not necessarily lead to an unfavorable outcome.
authors.affiliation: Servicio de Neurología, Hospital de São João, Porto, Portugal. angelasilva@mail.telepac.pt
authors.forename: A
authors.initials: A
authors.lastname: Silva
authors.forename: M J
authors.initials: MJ
authors.lastname: Sá
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001921:Brain / Q000473:pathology; D002648:Child; D003711:Demyelinating Diseases / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000453:epidemiology; D011174:Portugal / Q000453:epidemiology; D012189:Retrospective Studies; D012720:Severity of Illness Index
vernacular_title: Esclerosis múltiple de inicio juvenil.