title: Lipocalin 2 in cerebrospinal fluid as a marker of acute bacterial meningitis.
abstract: BACKGROUND
  Early differential diagnosis between acute bacterial and viral meningitis is problematic. We aimed to investigate whether the detection of lipocalin 2, a protein of the acute innate immunity response, may be used as a marker for acute bacterial meningitis.
  
  
  METHODS
  Transgenic mice expressing the human transferrin were infected by intraperitoneal route and were imaged. Cerebrospinal fluid (CSF) was sampled up to 48hours post- infection to measure lipocalin 2. We also tested a collection of 90 and 44 human CSF with confirmed acute bacterial or acute viral meningitis respectively.
  
  
  RESULTS
  Lipocalin 2 was detected after 5 h in CSF during experimental infection in mice. Lipocalin 2 levels were significantly higher (p < 0.0001) in patients with confirmed acute bacterial meningitis (mean 125 pg/mL, range 106-145 pg/mL) than in patients with acute viral meningitis (mean 2 pg/mL, range 0-6 pg/mL) with a sensitivity of 81%, a specificity of 93%, a positive predictive value of 96% and a negative predictive value of 71% in diagnosing acute bacterial meningitis.
  
  
  CONCLUSIONS
  Increased levels of lipocalin 2 in cerebrospinal fluid may discriminate between acute bacterial and viral meningitis in patients with clinical syndrome of meningitis.
authors.forename: Tamazoust
authors.initials: T
authors.lastname: Guiddir
authors.forename: Ala-Eddine
authors.initials: AE
authors.lastname: Deghmane
authors.forename: Dario
authors.initials: D
authors.lastname: Giorgini
authors.affiliation: Institut Pasteur, Invasive Bacterial Infections Unit and National Reference Centre for Meningococci, 28 Rue du Dr Roux, 75724 Paris, Cedex 15, France. mktaha@pasteur.fr.
authors.forename: Muhamed-Kheir
authors.initials: MK
authors.lastname: Taha
mesh_terms: D000209:Acute-Phase Proteins / Q000134:cerebrospinal fluid*; D000293:Adolescent; D000328:Adult; D000818:Animals; D015415:Biomarkers / Q000134:cerebrospinal fluid; D002352:Carrier Proteins; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D000071068:Lipocalin-2; D054834:Lipocalins / Q000134:cerebrospinal fluid*; D008297:Male; D016920:Meningitis, Bacterial / Q000134:cerebrospinal fluid*; D008587:Meningitis, Viral / Q000175:diagnosis; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D011518:Proto-Oncogene Proteins / Q000134:cerebrospinal fluid*; D012680:Sensitivity and Specificity; D014168:Transferrin
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; D002352:Carrier Proteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D014168:Transferrin