title: Ruling out bacteremia and bacterial meningitis in infants less than one month of age: is 48 hours of hospitalization necessary?
abstract: OBJECTIVE
  The appropriate duration of hospitalization for infants ≤ 30 days admitted for fever or other concerns for a serious bacterial infection is an understudied area. We sought to determine the risk of a positive, pathogenic bacterial culture of blood or cerebrospinal fluid (CSF) in this population beyond 24 hours after collection.
  
  
  METHODS
  This study was a retrospective review of 1145 infants aged ≤30 days who had a blood or CSF culture from 1999 to 2010 at Santa Clara Valley Medical Center, a county health system in San Jose, California. Time to notification and the probability of a positive culture result after 24 hours were calculated. Infants were considered high risk if they had either a white blood cell count <5000 or >15 000 per µL, a band count >1500 per µL, or an abnormal urinalysis.
  
  
  RESULTS
  We identified 1876 cultures (1244 blood, 632 CSF) in 1145 infants aged ≤30 days; 901 (79%) of 1145 were hospitalized and 408 (45%) of 901 hospitalizations were for fever without source (FWS). Thirty-one (2.7%) of the 1145 infants had pathogenic cultures; 6 of 1145 infants (0.5% [95% confidence interval: 0.2-1.1]) had a time to notification >24 hours. All 6 patients had FWS (1.5% of hospitalized FWS sample) and met high-risk criteria on presentation. No low-risk patients had a time to notification >24 hours. Low-risk characteristics were found in 57% (232 of 408) of the entire hospitalized FWS population.
  
  
  CONCLUSIONS
  Low-risk infants hospitalized for FWS or other concerns for serious bacterial infection may not need hospitalization for a full 48 hours simply to rule out bacteremia and bacterial meningitis.
authors.affiliation: School of Medicine, Stanford University, Stanford, California;
authors.forename: Vikram
authors.initials: V
authors.lastname: Fielding-Singh
authors.forename: David K
authors.initials: DK
authors.lastname: Hong
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Harris
authors.forename: John R
authors.initials: JR
authors.lastname: Hamilton
authors.forename: Alan R
authors.initials: AR
authors.lastname: Schroeder
keywords: diagnostic decision-making; meningitis; sepsis and shock