Epidemiology and Etiology of Invasive Bacterial Infection in Infants ≤60 Days Old Treated in Emergency Departments.

2018

2018 May 18

1097-6833

OBJECTIVES: To help guide empiric treatment of infants ≤60 days old with suspected invasive bacterial infection by describing pathogens and their antimicrobial susceptibilities.

STUDY DESIGN: Cross-sectional study of infants ≤60 days old with invasive bacterial infection (bacteremia and/or bacterial meningitis) evaluated in the emergency departments of 11 children's hospitals between July 1, 2011 and June 30, 2016. Each site's microbiology laboratory database or electronic medical record system was queried to identify infants from whom a bacterial pathogen was isolated from either blood or cerebrospinal fluid. Medical records of these infants were reviewed to confirm the presence of a pathogen and to obtain demographic, clinical, and laboratory data.

RESULTS: Of the 442 infants with invasive bacterial infection, 353 (79.9%) had bacteremia without meningitis, 64 (14.5%) had bacterial meningitis with bacteremia, and 25 (5.7%) had bacterial meningitis without bacteremia. The peak number of cases of invasive bacterial infection occurred in the second week of life; 364 (82.4%) infants were febrile. Group B streptococcus was the most common pathogen identified (36.7%), followed by Escherichia coli (30.8%), Staphylococcus aureus (9.7%), and Enterococcus spp (6.6%). Overall, 96.8% of pathogens were susceptible to ampicillin plus a third-generation cephalosporin, 96.0% to ampicillin plus gentamicin, and 89.2% to third-generation cephalosporins alone.

CONCLUSIONS: For most infants ≤60 days old evaluated in a pediatric emergency department for suspected invasive bacterial infection, the combination of ampicillin plus either gentamicin or a third-generation cephalosporin is an appropriate empiric antimicrobial treatment regimen. Of the pathogens isolated from infants with invasive bacterial infection, 11% were resistant to third-generation cephalosporins alone.

10.1016/j.jpeds.2018.04.033

J. Pediatr.

29784512

Risk Stratification of Febrile Infants ≤60 Days Old Without Routine Lumbar Puncture.

2018

2018 Nov 13

1098-4275

: media-1vid110.1542/5840460609001PEDS-VA_2018-1879 OBJECTIVES: To evaluate the Rochester and modified Philadelphia criteria for the risk stratification of febrile infants with invasive bacterial infection (IBI) who do not appear ill without routine cerebrospinal fluid (CSF) testing.

METHODS: We performed a case-control study of febrile infants ≤60 days old presenting to 1 of 9 emergency departments from 2011 to 2016. For each infant with IBI (defined as a blood [bacteremia] and/or CSF [bacterial meningitis] culture with growth of a pathogen), controls without IBI were matched by site and date of visit. Infants were excluded if they appeared ill or had a complex chronic condition or if data for any component of the Rochester or modified Philadelphia criteria were missing.

RESULTS: Overall, 135 infants with IBI (118 [87.4%] with bacteremia without meningitis and 17 [12.6%] with bacterial meningitis) and 249 controls were included. The sensitivity of the modified Philadelphia criteria was higher than that of the Rochester criteria (91.9% vs 81.5%; = .01), but the specificity was lower (34.5% vs 59.8%; < .001). Among 67 infants >28 days old with IBI, the sensitivity of both criteria was 83.6%; none of the 11 low-risk infants had bacterial meningitis. Of 68 infants ≤28 days old with IBI, 14 (20.6%) were low risk per the Rochester criteria, and 2 had meningitis.

CONCLUSIONS: The modified Philadelphia criteria had high sensitivity for IBI without routine CSF testing, and all infants >28 days old with bacterial meningitis were classified as high risk. Because some infants with bacteremia were classified as low risk, infants discharged from the emergency department without CSF testing require close follow-up.

10.1542/peds.2018-1879

Pediatrics

30425130

A Prediction Model to Identify Febrile Infants ≤60 Days at Low Risk of Invasive Bacterial Infection.

2019

2019 Jun 05

1098-4275

OBJECTIVES: To derive and internally validate a prediction model for the identification of febrile infants ≤60 days old at low probability of invasive bacterial infection (IBI).

METHODS: We conducted a case-control study of febrile infants ≤60 days old who presented to the emergency departments of 11 hospitals between July 1, 2011 and June 30, 2016. Infants with IBI, defined by growth of a pathogen in blood (bacteremia) and/or cerebrospinal fluid (bacterial meningitis), were matched by hospital and date of visit to 2 control patients without IBI. Ill-appearing infants and those with complex chronic conditions were excluded. Predictors of IBI were identified with multiple logistic regression and internally validated with 10-fold cross-validation, and an IBI score was calculated.

RESULTS: We included 181 infants with IBI (155 [85.6%] with bacteremia without meningitis and 26 [14.4%] with bacterial meningitis) and 362 control patients. Twenty-three infants with IBI (12.7%) and 138 control patients (38.1%) had fever by history only. Four predictors of IBI were identified (area under the curve 0.83 [95% confidence interval (CI): 0.79-0.86]) and incorporated into an IBI score: age <21 days (1 point), highest temperature recorded in the emergency department 38.0-38.4°C (2 points) or ≥38.5°C (4 points), absolute neutrophil count ≥5185 cells per μL (2 points), and abnormal urinalysis results (3 points). The sensitivity and specificity of a score ≥2 were 98.8% (95% CI: 95.7%-99.9%) and 31.3% (95% CI: 26.3%-36.6%), respectively. All 26 infants with meningitis had scores ≥2.

CONCLUSIONS: Infants ≤60 days old with fever by history only, a normal urinalysis result, and an absolute neutrophil count <5185 cells per μL have a low probability of IBI.

10.1542/peds.2018-3604

Pediatrics

31167938