Background: Well-appearing young infants with focal bacterial infections present to the emergency department (ED) and are often admitted for a sepsis evaluation of blood, urine, and spinal fluid. However, the risk of concomitant systemic infections (CSI) in this population is not well reported, specifically comparing febrile to afebrile infants. We hypothesized that afebrile, well-appearing infants under two months of age with a defined focal bacterial infection on exam have a very low risk of CSI.
Methods: This retrospective study was conducted at an urban, academic, tertiary care pediatric hospital ED on patients seen from January 2000-December 2005. Eligible infants were less than 60 days of age, well-appearing on exam, and with normal-for-age vital signs who presented with a focal bacterial infection on exam. Exclusion criteria included immunodeficiency, indwelling catheter, previous admission for bacterial infection, or current use of systemic antibiotics. Main study outcome was risk of CSI in febrile and afebrile groups.
Results: One hundred ninety seven patients were included in the study population. Of these, 39 were febrile and 158 were afebrile. Four patients had a documented CSI: one case of S. pneumoniae bacteremia and three cases of E. coli urinary tract infection. Of these 4 infants, 3 were febrile (7.7% CSI risk) and 1 was afebrile (0.6%). Febrile infants had a significantly higher risk of CSI (OR 13.1, 95% CI 1.3, 129.5).
Conclusions: CSI is very uncommon in afebrile, well-appearing infants under 60 days of age with a focal bacterial infection.