title: Procalcitonin in cerebrospinal fluid in meningitis: a prospective diagnostic study.
abstract: Bacterial meningitis is a severe but treatable condition. Clinical symptoms may be ambiguous and current diagnostics lack sensitivity and specificity, complicating diagnosis. Procalcitonin (PCT) is a protein that is elevated in serum in bacterial infection. We aimed to assess the value of PCT in cerebrospinal fluid (CSF) in the diagnosis of bacterial meningitis.
  
  
  
  We included patients with bacterial meningitis, both community acquired and post neurosurgery. We included two comparison groups: patients with viral meningitis and patients who underwent lumbar punctures for noninfectious indications. We calculated mean differences and 95% confidence intervals of procalcitonin in CSF and plasma in patients with and without bacterial meningitis.
  
  
  
  Average PCT concentrations in CSF were 0.60 ng mL-1(95% CI: 0.29-0.92) in the bacterial meningitis group (n= 26), 0.81 (95% CI: 0.33-1.28) in community-acquired meningitis (n= 16) and 0.28 (95% CI: 0.10-0.45) in postneurosurgical meningitis (n= 10), 0.10 ng mL-1(95% CI: 0.08-0.12) in the viral meningitis group (n= 14) and 0.08 ng mL-1(95% CI: 0.06-0.09) in the noninfectious group (n= 14). Mean difference of PCT-CSF between patients with community-acquired bacterial meningitis and with viral meningitis was 0.71 ng mL-1(95% CI: 0.17-1.25) and 0.73 ng mL-1(95% CI: 0.19-1.27) for community-acquired bacterial meningitis versus the noninfectious group. The median PCT CSF: plasma ratio was 5.18 in postneurosurgical and 0.18 in community-acquired meningitis (IQR 4.69 vs. 0.28).
  
  
  
  Procalcitonin in CSF was significantly higher in patients with bacterial meningitis when compared with patients with viral or no meningitis. PCT in CSF may be a valuable marker in diagnosing bacterial meningitis, and could become especially useful in patients after neurosurgery.
authors.affiliation: Department of Neurology MCH Westeinde The Hague The Netherlands.
authors.forename: Imanda M E
authors.initials: IM
authors.lastname: Alons
authors.affiliation: Department of Clinical chemistry LabWest/MCH Westeinde The Hague The Netherlands.
authors.forename: Rolf J
authors.initials: RJ
authors.lastname: Verheul
authors.affiliation: Department of Clinical chemistry LabWest/MCH Westeinde The Hague The Netherlands.
authors.forename: Irma
authors.initials: I
authors.lastname: Kuipers
authors.affiliation: Department of Neurology MCH Westeinde The Hague The Netherlands.
authors.forename: Korné
authors.initials: K
authors.lastname: Jellema
authors.affiliation: Department of Neurology LUMC Leiden The Netherlands.
authors.forename: Marieke J H
authors.initials: MJ
authors.lastname: Wermer
authors.affiliation: Department of Clinical Epidemiology LUMC Leiden The Netherlands; Department of Neurology and Neurosurgery Brain Center Rudolph Magnus UMC Utrecht Utrecht The Netherlands; Julius Center for Health Sciences and Patient Care UMC Utrecht Utrecht The Netherlands.
authors.forename: Ale
authors.initials: A
authors.lastname: Algra
authors.affiliation: Department of Clinical chemistry LabWest/MCH Westeinde The Hague The Netherlands.
authors.forename: Gabriëlle
authors.initials: G
authors.lastname: Ponjee
mesh_terms: D000328:Adult; D002116:Calcitonin / Q000097:blood / Q000134:cerebrospinal fluid*; D017714:Community-Acquired Infections / Q000097:blood / Q000134:cerebrospinal fluid / Q000175:diagnosis; D005260:Female; D006801:Humans; D008297:Male; D016920:Meningitis, Bacterial / Q000097:blood / Q000134:cerebrospinal fluid* / Q000175:diagnosis / Q000382:microbiology; D008587:Meningitis, Viral / Q000097:blood / Q000134:cerebrospinal fluid / Q000175:diagnosis; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D002116:Calcitonin
keywords: bacterial meningitis; cerebrospinal fluid; diagnostic marker; external ventricular drain; meningitis; neurosurgical intervention; procalcitonin