Epidemiology of Bacteremia in Febrile Infants in the United States

Abstract

WHAT'S KNOWN ON THIS SUBJECT: Bacteremia occurs in 2.2% of febrile infants who have a blood culture drawn. Regional data suggest that Escherichia coli, group B Streptococcus, and Staphylococcus aureus are leading causes; however, the geographic boundaries of these data limit universal applicability. WHAT THIS STUDY ADDS:This is the first national study examining epidemiology of bacteremia in febrile infants admitted to a general inpatient unit. The most common pathogens were Escherichia coli (42%), group B Streptococcus (23%), and Streptococcus pneumoniae (6%). No Listeria monocytogenes was identified.abstract BACKGROUND: Fever in infants is a common clinical dilemma. The objective of this study was to present data from hospital systems across the northeast, southeast, mid-west, and western United States to identify the pathogens causing bacteremia in febrile infants admitted to general care units. METHODS:This was a retrospective review of positive blood culture results in febrile infants aged #90 days admitted to a general care unit across 6 hospital systems. Data were collected from January 1, 2006 through December 31, 2012 from emergency departments and general inpatient units. Cultures from ICUs, central lines, or infants who had complex comorbidities were excluded, as were repeat cultures positive for the same bacteria. Common contaminants were considered pathogens if they were treated as such. RESULTS:We identified 181 cases of bacteremia in 177 infants. The most common pathogen was Escherichia coli (42%), followed by group B Streptococcus (23%). Streptococcus pneumoniae was more likely in older infants (P = .01). Non-low-risk bacteremic infants were more likely to have E coli or group B Streptococcus than low-risk bacteremic infants. We identified no cases of Listeria monocytogenes. Variation between sites was minimal.CONCLUSIONS: This is the largest and most geographically diverse study to date examining the epidemiology of bacteremia in infants.We suggest E coli is the most common cause of bacteremia in previously healthy febrile infants admitted to a general inpatient unit. We identified no cases of L monocytogenes and question whether empirical therapy remains necessary for this pathogen. Pediatrics 2013;132:990-996

Validation of the “Step-by-Step” Approach in the Management of Young Febrile Infants

“…Improvement in the perinatal antibiotic prophylaxis has reduced the incidence of S. agalactiae early-onset sepsis, 35 -37 E coli is nowadays the leading cause of bacteremia in this population, 6,7,17,24 and Listeria is rarely involved. 6,7,17,24 On the other hand, new biomarkers that have been shown to be better predictors of IBI have been included in many management protocols. Curiously, the Lab-score, developed less than 10 years ago, revealed a lower performance compared with previously published studies.…”

“…Regardless of the protocol used, current adherence to any of them in clinical practice is low. 4,5 Changes in the epidemiology of bacterial pathogens in the last decades 6,7 and introduction of biomarkers such as C-reactive protein (CRP) and, more recently, procalcitonin (PCT) could justify this low adherence rate and make several authors advocate for a more individualized approach. The latter includes new biomarkers and a reduction in lumbar puncture rates, antibiotic treatments, or in-hospital admission for many well-appearing infants outside the neonatal period.…”

Intravenous antibiotic durations for common bacterial infections in children: When is enough enough?

“…15 Even in infants too young to benefit directly from vaccination, the epidemiology of bacteremia has changed considerably over the last few decades, with E coli and GBS constituting the majority (65%-77%) of cases. 16,17 We will limit this review on bacteremia to these 2 organisms in young infants.…”

“…Most cases of E coli bacteremia are associated with UTI (91%-98%), 16,17 and most bacteremic UTIs (88%-92%) are caused by E coli. [18][19][20][21] There are no official recommendations for the duration of treatment of bacteremic UTI, and only a limited amount of evidence can be gleaned from existing studies.…”

The Never-ending Quest to Detect Bacteremia: Time for a Culture Change

“…For example, Staphylococcus aureus is emerging as a leading cause of bacteremia in otherwise healthy young infants. 3,19,20 However, S aureus is also a common skin organism. In infants without SSTIs, how should we treat S aureus bacteremia?…”