title: Blood Culture in Evaluation of Pediatric Community-Acquired Pneumonia: A Systematic Review and Meta-analysis.
abstract: OBJECTIVE
  Current guidelines strongly recommend collection of blood cultures (BCs) in children requiring hospitalization for presumed moderate to severe bacterial community-acquired pneumonia (CAP). Our objective was to systematically review the international pediatric literature to evaluate how often BCs are positive in hospitalized children with CAP, identify the most commonly isolated pathogens, and determine the impact of positive BCs on clinical management.
  
  
  METHODS
  We identified articles in PubMed and Scopus published from January 1970 through December 2013 that addressed BCs in children with CAP. We extracted total number of BCs collected and prevalence of positive BCs and used meta-regression to evaluate whether subgroups had any impact on prevalence.
  
  
  RESULTS
  Meta-analysis showed that the overall prevalence of positive BCs was 5.14% (95% confidence interval 3.61-7.28). Studies focusing on severe CAP had a significant effect on prevalence (P=.008), at 9.89% (95% CI 6.79-14.19) compared with 4.17% (95% confidence interval 2.79-6.18) for studies not focusing on severe CAP. The most commonly isolated organisms were Streptococcus pneumoniae (76.7%) followed by Haemophilus influenzae (3.1%) and Staphylococcus aureus (2.1%). Contaminants accounted for 14.7%. Only 3 studies reported on BC-driven change in management, with contrasting findings.
  
  
  CONCLUSIONS
  BCs in pediatric CAP identified organisms in only a small percentage of patients, predominantly S. pneumoniae. False-positive BC rates can be substantial. The 3 studies that examined BC-driven changes in management had conflicting results. This systematic review was limited by heterogeneous case definitions, which may overestimate the true prevalence of positive BCs in hospitalized children.
authors.affiliation: Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota Masonic Children's Hospital, Minneapolis, Minnesota; irohtam@umn.edu.
authors.forename: Pui-Ying
authors.initials: PY
authors.lastname: Iroh Tam
authors.affiliation: University of Minnesota Medical School, Minneapolis, Minnesota;
authors.forename: Ethan
authors.initials: E
authors.lastname: Bernstein
authors.affiliation: Department of Biostatistics, University of Minnesota School of Public Health, Minneapolis, Minnesota; and.
authors.forename: Xiaoye
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Pediatrics, Division of Pediatric Infectious Diseases and Immunology, University of Minnesota Masonic Children's Hospital, Minneapolis, Minnesota; Department of Laboratory Medicine and Pathology, University of Minnesota Medical Center, Minneapolis, Minnesota.
authors.forename: Patricia
authors.initials: P
authors.lastname: Ferrieri
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000097:blood* / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010372:Pediatrics / Q000706:statistics & numerical data*; D018410:Pneumonia, Bacterial / Q000097:blood* / Q000175:diagnosis*; D055815:Young Adult
keywords: Haemophilus influenzae type b vaccine; Streptococcus pneumoniae; bacteremia; blood culture; community-acquired pneumonia; meta-analysis; pediatric; pneumococcal conjugate vaccine; systematic review