title: [Validation of a clinical prediction rule to distinguish bacterial from aseptic meningitis].
abstract: BACKGROUND
  Despite most meningitis are not bacterial, antibiotics are usually administered on admission because bacterial meningitis is difficult to be rule-out. Distinguishing bacterial from aseptic meningitis on admission could avoid inappropriate antibiotic use and hospitalization. We aimed to validate a clinical prediction rule to distinguish bacterial from aseptic meningitis in children, on arriving to the emergency room.
  
  
  METHODS
  This prospective study included patients aged < 19 years with meningitis. Cerebrospinal fluid (CSF) and peripheral blood neutrophil count were obtained from all patients. The BMS (Bacterial Meningitis Score) described by Nigrovic (Pediatrics 2002; 110: 712), was calculated: positive CSF Gram stain= 2 points, CSF absolute neutrophil count > or = 1000 cells/mm(3), CSF protein > or = 80 mg/dl, peripheral blood absolute neutrophil count > or = 10.000/mm(3), seizure = 1 point each. Sensitivity (S), specificity (E), positive and negative predictive values (PPV and NPV), positive and negative likelihood ratios (PLR and NLR) of the BMS to predict bacterial meningitis were calculated.
  
  
  RESULTS
  Seventy patients with meningitis were included (14 bacterial meningitis). When BMS was calculated, 25 patients showed a BMS= 0 points, 11 BMS= 1 point, and 34 BMS > or = 2 points. A BMS = 0 showed S: 100%, E: 44%, VPP: 31%, VPN: 100%, RVP: 1,81 RVN: 0. A BMS > or = 2 predicted bacterial meningitis with S: 100%, E: 64%, VPP: 41%, VPN: 100%, PLR: 2.8, NLR:0.
  
  
  CONCLUSIONS
  Using BMS was simple, and allowed identifying children with very low risk of bacterial meningitis. It could be a useful tool to assist clinical decision making.
authors.affiliation: Docencia e Investigación, Hospital General de Niños Pedro de Elizalde.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Agüero
authors.forename: María C
authors.initials: MC
authors.lastname: Davenport
authors.forename: María de la P
authors.initials: Mde L
authors.lastname: Del Valle
authors.forename: Paulina
authors.initials: P
authors.lastname: Gallegos
authors.forename: Ana L
authors.initials: AL
authors.lastname: Kannemann
authors.forename: Vivian
authors.initials: V
authors.lastname: Bokser
authors.forename: Fernando
authors.initials: F
authors.lastname: Ferrero
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D005544:Forecasting; D006801:Humans; D007223:Infant; D008297:Male; D008582:Meningitis, Aseptic / Q000175:diagnosis*; D016920:Meningitis, Bacterial / Q000175:diagnosis*; D011446:Prospective Studies; D055815:Young Adult