title: Intrapartum colonization with Streptococcus pneumoniae, early-onset sepsis and deficient specific neonatal immune responses.
abstract: BACKGROUND
  Intrapartum colonization with Streptococcus pneumoniae (S. pneumoniae) is a rare but important risk factor for severe courses of early-onset sepsis (EOS) in the newborn, as underlined in the case of a preterm infant born after 32 weeks of gestation described here. One potential explanation could be an immature immune response of the neonate to S. pneumoniae, however, immunological data in term and preterm infants are scarce.
  
  
  METHODS
  To determine the neonatal immune responses to S. pneumoniae, flow-cytometry analysis of the cytokine production by CD14+ cells was performed after full pathogen stimulation with S. pneumoniae (serotype 18C, derived from an EOS case described here) of cord blood of 10 term (37-41 gestational weeks) and 6 preterm (31-32 gestational weeks) neonates, compared to peripheral venous blood samples of 10 healthy adults in vitro.
  
  
  RESULTS
  Neonatal cytokine responses of term and preterm infants to S. pneumoniae are diminished compared to adults. The quantities of cytokine expression were comparable to immune responses induced by other important gram-positive pathogens of EOS such as Streptococcus agalacticae.
  
  
  CONCLUSIONS
  Severe courses of EOS with S. pneumoniae may be attributed to remarkable deficiencies of the specific neonatal immune response. To protect the neonate from invasive pneumococcal disease, maternal immunization may be an important prevention strategy, as protective antibodies can be transferred through the placenta and vaccination of pregnant women may reduce colonization.
authors.affiliation: Department of Pediatrics, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
authors.forename: Kirstin
authors.initials: K
authors.lastname: Faust
authors.forename: Martin
authors.initials: M
authors.lastname: Demmert
authors.forename: Meike
authors.initials: M
authors.lastname: Bendiks
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Göpel
authors.forename: Egbert
authors.initials: E
authors.lastname: Herting
authors.forename: Christoph
authors.initials: C
authors.lastname: Härtel
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D018950:Lipopolysaccharide Receptors / Q000276:immunology; D011008:Pneumococcal Infections / Q000276:immunology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy / Q000276:immunology / Q000382:microbiology; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy / Q000276:immunology*; D018805:Sepsis / Q000276:immunology* / Q000635:transmission; D012720:Severity of Illness Index; D013296:Streptococcus pneumoniae
chemical_list: D000900:Anti-Bacterial Agents; D016207:Cytokines; D018950:Lipopolysaccharide Receptors