Epidemiology of Bacteremia in Previously Healthy Febrile Infants: A Follow-up Study

OBJECTIVE: Describe the etiology of bacteremia among a geographically diverse sample of previously well infants with fever admitted for general pediatric care and to characterize demographic and clinical characteristics of infants with bacteremia according to bacterial etiology. We hypothesized that the epidemiology of bacteremia in febrile infants from a geographically diverse cohort would show similar results to smaller or single-center cohorts previously reported.

METHODS: This was a retrospective review of positive, pathogenic blood cultures in previously healthy, febrile infants≤90 days old admitted to a general unit. In total, there were 17 participating sites from diverse geographic regions of the United States. Cultures were included if the results were positive for bacteria, obtained from an infant 90 days old or younger with a temperature≥38.0°C, analyzed using an automated detection system, and treated as pathogenic.

RESULTS: Escherichia coli was the most prevalent species, followed by group B Streptococcus, Streptococcus viridans, and Staphylococcus aureus. Among the most prevalent bacteria, there was no association between gender and species (Ps>.05). Age at presentation was associated only with Streptococcus pneumoniae. There were no cases of Listeria monocytogenes.

CONCLUSIONS: Our study confirms the data from smaller or single-center studies and suggests that the management of febrile well-appearing infants should change to reflect the current epidemiology of bacteremia. Further research is needed into the role of lumbar puncture, as well as the role of Listeria and Enterococcus species in infantile bacteremia.