Evaluation, management, and outcome of focal bacterial infections (FBIs) in nontoxic infants under two months of age

Abstract

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. Journal of Hospital Medicine 2010;5:76–82. © 2010 Society of Hospital Medicine.

Outcomes After Skin and Soft Tissue Infection in Infants 90 Days Old or Younger

“…Although the study included a total of 197 patients, in the subset of patients with SSTIs (n 5 136), 3 patients (2.2%, all of whom were febrile) had UTI or IBI (1 with Streptococcus pneumoniae bacteremia and 2 with Escherichia coli UTI). 8 Because the mechanism of UTI with SSTI is not apparent, it is worth noting that the authors of this article did describe a limitation of their study as being the definition of UTI based on culture (with no colony-forming unit specification) alone without supportive urinalysis findings. 8 Although our study used a similar culture-specific definition of UTI, we did maintain a threshold of $50 000 colony forming units/mL of a single organism.…”

“…8,10,11 One study of 104 afebrile infants #28 days who presented to the ED for SSTI found that none had IBI. 10 Another study of infants #30 days identified as having superficial or invasive S aureus infection found that of the 68 patients (total study cohort 126 patients) with cellulitis/abscess, 2 (3%) had bacteremia and none had concomitant UTI or meningitis.…”

“…[4][5][6][7] Given the risks of UTI/IBI in febrile infants in this age group, many infants who present with SSTI are evaluated for additional concomitant bacterial infections regardless of fever status. [8][9][10] Previous single-center studies in tertiary children' s hospitals in urban settings have explored risks of UTI or IBI in infants with SSTI or Staphylococcus aureus infections; however, revisits for treatment failures or missed UTI/IBI outcomes may not have been captured because of the study setting. 8,10,11 Our study, using a multicentered approach over a range of hospital types including rural and urban settings in a network well suited to capture missed concomitant infections or treatment failures, could help to guide optimal clinical management including indication for workup of concomitant infections and follow-up planning.…”

“…[8][9][10] Previous single-center studies in tertiary children' s hospitals in urban settings have explored risks of UTI or IBI in infants with SSTI or Staphylococcus aureus infections; however, revisits for treatment failures or missed UTI/IBI outcomes may not have been captured because of the study setting. 8,10,11 Our study, using a multicentered approach over a range of hospital types including rural and urban settings in a network well suited to capture missed concomitant infections or treatment failures, could help to guide optimal clinical management including indication for workup of concomitant infections and follow-up planning. Therefore, our objective was to describe clinical outcomes for infants presenting to the hospital for concern of SSTI (with and without fever) including rates of UTI, IBI, and hospital revisit for treatment failure or missed concomitant bacterial infection as well as factors associated with treatment failure.…”

Question 2: Is a lumbar puncture necessary in an afebrile newborn infant with localised skin and soft tissue infection?

“…The major limitations of the studies by Kharazmi et al and Vidwan and Geis are the low rate of performed LP (22 and 36%) and lack of follow-up data of enrolled infants which bear the potential for missed diagnosis of occult meningitis. No information regarding pleocytosis was provided in either of these studies 2 4. Walsh and McIntosh's work lacks stratification of data by fever status, and the number of infants that underwent an LP was relatively low (22%), which again raises concerns about missed diagnosis of occult meningitis 5…”