title: The clinical presentation of acute bacterial meningitis varies with age, sex and duration of illness.
abstract: OBJECTIVE
  This Swedish study reviewed differences in clinical presentation and laboratory findings of acute bacterial meningitis in children aged one month to 17 years in Västerbotten County, Sweden.
  
  
  METHODS
  A register-based study was performed for the period 1986 to 2013 using the Västerbotten County Council's patient registration and laboratory records at the Department of Laboratory Medicine at Umeå University Hospital. The medical records were reviewed to extract data and confirm the diagnosis.
  
  
  RESULTS
  We found 103 cases of acute bacterial meningitis, and Haemophilus influenzae was the most common pathogen, causing 40.8% of all cases, followed by Streptococcus pneumoniae at 30.1% and Neisseria meningitidis at 9.7%. Significant differences in clinical presentation and laboratory findings were found. Younger children were more unwell than older ones and had more diffuse symptoms on admission. In addition, important sex-related differences were found that might explain the higher case fatality rates for boys than girls. For example, boys tended to have a higher disturbance in the blood-brain barrier, which is known to be a negative prognostic factor.
  
  
  CONCLUSIONS
  This study showed that clinical presentation for acute bacterial meningitis varied with age and sex and, to a lesser extent, on the duration of the illness.
authors.affiliation: Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden.
authors.forename: Urban
authors.initials: U
authors.lastname: Johansson Kostenniemi
authors.affiliation: Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Norman
authors.affiliation: Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden.
authors.forename: Malin
authors.initials: M
authors.lastname: Borgström
authors.affiliation: Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden.
authors.forename: Sven Arne
authors.initials: SA
authors.lastname: Silfverdal
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D016920:Meningitis, Bacterial / Q000175:diagnosis*; D012737:Sex Factors; D013997:Time Factors
keywords: Bacterial meningitis; Blood-brain barrier; Clinical presentation; Haemophilus influenzae laboratory diagnosis