title: Interleukin-6 analysis of 572 consecutive CSF samples from neurological disorders: A special focus on neuromyelitis optica.
abstract: BACKGROUND
  Elevation of cerebrospinal fluid (CSF) interleukin (IL)-6 has been reported in various neurological disorders but has never been systematically analyzed. Our main objectives are to compare the CSF IL-6 levels among various neurological disorders and to evaluate the significance of CSF IL-6 measurements for the diagnosis of neuromyelitis optica (NMO).
  
  
  METHODS
  We retrospectively investigated the IL-6 levels of 572 consecutive CSF samples in patients with various neurological disorders. Additionally, the associations between clinical manifestations in NMO patients and CSF IL-6 levels were closely investigated.
  
  
  RESULTS
  Among the neurological disorders, patients with NMO had the highest CSF IL-6 level. Receiver operating characteristic analysis found the optimal cutoff CSF IL-6 value for diagnosing NMO as 7.8pg/ml, and the sensitivity and specificity were 0.7317 and 0.7694, respectively. In NMO, CSF IL-6 levels were correlated with the length of the spinal cord lesion and anti-aquaporin-4 antibody-positivity and decreased after treatment.
  
  
  CONCLUSIONS
  CSF IL-6 can be high in various inflammatory and non-inflammatory CNS disorders, but its upregulation appears to be the most remarkable in NMO.
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan. Electronic address: auzawa@chiba-u.jp.
authors.forename: Akiyuki
authors.initials: A
authors.lastname: Uzawa
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Mori
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Masuda
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Ohtani
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Uchida
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan; Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Setsu
authors.initials: S
authors.lastname: Sawai
authors.affiliation: Department of Neurology, Graduate School of Medicine, Chiba University, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kuwabara
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000134:cerebrospinal fluid*; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000134:cerebrospinal fluid*; D012016:Reference Values
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6
keywords: Biomarker; Cerebrospinal fluid; Cutoff; Interleukin-6; Neuromyelitis optica