title: Lipopolysaccharide binding protein is a potential marker for invasive bacterial infections in children.
abstract: BACKGROUND
  The aim of this study was to test the hypothesis that elevated lipopolysaccharide binding protein (LBP) serum concentration is a useful marker in the early diagnosis of invasive bacterial infection in children. We measured LBP in serum and cerebrospinal fluid (CSF) of children with proven invasive infection caused by Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis.
  
  
  METHODS
  Samples were collected from 39 children (aged 2 months to 17 years) with bacterial sepsis (n = 19) or meningitis (n = 20). Bacterial infection was diagnosed when a blood or CSF culture was positive and clinical signs of invasive infection were present. The control group consisted of serum (n = 60) and CSF (n = 19) samples from children with neurologic disease, juvenile idiopathic arthritis or viral infection. In 10 patients with bacterial infection, follow-up samples (24 and 48 hours) were available. LBP values were measured by an immunochemiluminescence analyzer (IMMULITE; DPC Biermann, Bad Nauheim, Germany) and compared with tumor necrosis factor-alpha and interleukin-8 concentrations.
  
  
  RESULTS
  The median LBP serum concentrations in patients with bacterial infection were markedly elevated compared with the control groups (45.0 [33.1-55.2] versus 8.3 [6.8-10.1] microg/mL [median and 5-95% confidence interval]; P < 0.0001). Follow-up serum values of LBP were persistently elevated despite adequate antibiotic treatment, whereas tumor necrosis factor-alpha and interleukin-8 concentrations decreased. In contrast, LBP concentrations in the CSF were below the detection limit of 0.5 microg/mL in 67% of patients with bacterial meningitis (median <0.5 microg/mL), whereas tumor necrosis factor-alpha and interleukin-8 levels were highly elevated.
  
  
  CONCLUSIONS
  LBP serum concentration is elevated in serum of children with invasive bacterial infection and could be a promising diagnostic marker.
authors.affiliation: Centre for Pediatrics and Adolescent Medicine, University Hospital of Freiburg, Freiburg, Germany.
authors.forename: Katja M
authors.initials: KM
authors.lastname: Ubenauf
authors.forename: Marcus
authors.initials: M
authors.lastname: Krueger
authors.forename: Philipp
authors.initials: P
authors.lastname: Henneke
authors.forename: Reinhard
authors.initials: R
authors.lastname: Berner
mesh_terms: D000209:Acute-Phase Proteins; D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002352:Carrier Proteins / Q000097:blood*; D002555:Cerebrospinal Fluid / Q000737:chemistry; D002648:Child; D002675:Child, Preschool; D006192:Haemophilus Infections / Q000175:diagnosis* / Q000188:drug therapy; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D007118:Immunoassay; D007223:Infant; D016209:Interleukin-8 / Q000097:blood; D008163:Luminescent Measurements; D008562:Membrane Glycoproteins / Q000097:blood*; D016920:Meningitis, Bacterial / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D008589:Meningococcal Infections / Q000175:diagnosis* / Q000188:drug therapy; D009345:Neisseria meningitidis / Q000302:isolation & purification; D011008:Pneumococcal Infections / Q000175:diagnosis* / Q000188:drug therapy; D018805:Sepsis / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D044967:Serum / Q000737:chemistry; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D000099231:Lipopolysaccharide-Binding Protein
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; D002352:Carrier Proteins; D016209:Interleukin-8; D008562:Membrane Glycoproteins; D014409:Tumor Necrosis Factor-alpha; D000099231:Lipopolysaccharide-Binding Protein