Is 15 days an appropriate cut-off age for considering serious bacterial infection in the management of febrile infants?

Performance of Febrile Infant Algorithms by Duration of Fever

OBJECTIVES

To analyze the performance of commonly used blood tests in febrile infants ≤90 days of age to identify patients at low risk for invasive bacterial infection (bacterial pathogen in blood or cerebrospinal fluid) by duration of fever.

METHODS

We conducted a secondary analysis of a prospective single-center registry that includes all consecutive infants ≤90 days of age with fever without a source evaluated at 1 pediatric emergency department between 2008 and 2021. We defined 3 groups based on caregiver-reported hours of fever (<2, 2-12, and ≥12) and analyzed the performance of the biomarkers and Pediatric Emergency Care Applied Research Network, American Academy of Pediatrics, and Step-by-Step clinical decision rules.

RESULTS

We included 2411 infants; 76 (3.0%) were diagnosed with an invasive bacterial infection. The median duration of fever was 4 (interquartile range, 2-12) hours, with 633 (26.3%) patients with fever of <2 hours. The area under the curve was significantly lower in patients with <2 hours for absolute neutrophil count (0.562 vs 0.609 and 0.728) and C-reactive protein (0.568 vs 0.760 and 0.812), but not for procalcitonin (0.749 vs 0.780 and 0.773). Among well-appearing infants older than 21 days and negative urine dipstick with <2 hours of fever, procalcitonin ≥0.14 ng/mL showed a better sensitivity (100% with specificity 53.8%) than that of the combination of biomarkers of Step-by-Step (50.0% and 82.2%), and of the American Academy of Pediatrics and Pediatric Emergency Care Applied Research Network rules (83.3% and 58.3%), respectively.

CONCLUSIONS

The performance of blood biomarkers, except for procalcitonin, in febrile young infants is lower in fever of very short duration, decreasing the accuracy of the clinical decision rules.

Approach to the Febrile Infant (<3 Months)

ABSTRACT

Evaluation and management of the febrile infant has long been an area of variability. Recent guidelines were released by the American Academy of Pediatrics in August 2021 to help provide evidence-based clinical guidelines to decrease variability and improve outcomes.1 These guidelines largely focus on management and treatment guidelines for 3 age groups: 8 to 21 days, 22 to 28 days, and 29 to 60 days. The inclusion criteria for these guidelines are previously healthy, term infants born at 37 weeks gestation or later, with a temperature of 100.4°F (38°C) or higher. The most significant changes to historical practice are in the 22- to 28-day and 29- to 60-day age groups. If initial laboratory work is reassuring, patients may not need cerebrospinal fluid studies, and patients may be monitored at home or at the hospital using shared decision-making with the family.

Outpatient parenteral antimicrobial therapy: how young is too young?

OBJECTIVE

To report the use, and assess the efficacy and outcomes of outpatient parenteral antimicrobial therapy (OPAT) in neonates (≤28 days of age), compared with older infants (1-12 months of age).

DESIGN

A prospective 8-year observational study from September 2012 to September 2020.

SETTING

The Hospital-in-the-Home (HITH) programme of the Royal Children's Hospital Melbourne.

PATIENTS

Neonatal patients (≤28 days of age) were compared with older infants (1-12 months of age) receiving OPAT.

INTERVENTIONS

Data were collected including demographics, diagnosis, type of venous access and antibiotic choice.

MAIN OUTCOME MEASURES

Success of OPAT, antibiotic appropriateness, complications and readmission rate.

RESULTS

There were 76 episodes for which neonates were admitted to HITH for OPAT, and 405 episodes for older infants. Meningitis was the most common diagnosis in both groups (59% and 35%, respectively); the most frequently prescribed antibiotic was ceftriaxone for both groups (61% and 49%). A positive bacterial culture was less frequent in neonates (38% vs 53%, p=0.02). Vascular access complication rate was 19% in neonates compared with 13% in older infants (p=0.2) with no central line-associated bloodstream infection in either group. Rates of appropriate antibiotic prescribing were similarly high between groups (93% vs 90%, p=0.3). The OPAT course was successfully completed in 74 of 74 (100%) neonates and 380 of 396 (96%) older infants (p=0.09). The unplanned readmission rate was low: 4 of 76 (5%) neonates and 27 of 405 (7%) older infants.

CONCLUSIONS

OPAT is a safe and effective way of providing antibiotics to selected clinically stable neonatal patients. While appropriate antibiotic use was common, improvements can still be made.

Management and Outcome of Febrile Infants ≤60 days, With Emphasis on Infants ≤21 Days Old, in Swedish Pediatric Emergency Departments

BACKGROUND

Management of febrile infants ≤60 days of age varies, and the age for routine investigations and antibiotic-treatment is debated. The American Academy of Pediatrics recommended age threshold for lumbar puncture (LP) is 21 days and for blood culture 60 days. We describe management and adverse outcome of febrile infants ≤60 days old, in Sweden.

METHODS

Retrospective cross-sectional study of infants ≤60 days of age with fever without source evaluated in 4 University pediatric emergency departments, between 2014 and 2017. Adverse outcome was defined as delayed-treated invasive bacterial infection (IBI: meningitis or bacteremia).

RESULTS

We included 1701 infants. In infants ≤21 days old, LP was performed in 16% (95% CI: 12-20) and blood culture in 43% (95% CI: 38-48). Meningitis was diagnosed in 5 (1.3%; 95% CI: 0.4-3.0) and bacteremia in 12 (4.5%; 95% CI: 2.6-7.0) infants. Broad-spectrum antibiotics were not administered to 66% (95% CI: 61-71), of which 2 (0.8%; 95% CI: 0.1-2.8) diagnosed with IBI (1 meningitis and 1 bacteremia). In the 29-60 days age group, blood culture was performed in 21% (95% CI: 19-24), and broad-spectrum antibiotics were not administered to 84% (95% CI: 82-86), with no case of delayed-treated bacteremia.

CONCLUSIONS

The rates of LP, blood culture and broad-spectrum antibiotics were low. Despite that, there were few delayed-treated IBIs, but 2 of the 17 infants ≤21 days of age with IBI were not timely treated, which prompts the need for a safer approach for this age group. Also, the utility of routine blood culture for all febrile infants 29-60 days old could be questioned.

Rochester Criteria and Yale Observation Scale Score to Evaluate Febrile Neonates with Invasive Bacterial Infection

BACKGROUND

Febrile neonates undergo lumbar puncture (LP), empiric antibiotic administration, and admission for increased risk of invasive bacterial infection (IBI), defined as bacteremia and meningitis.

OBJECTIVE

Measure IBI prevalence in febrile neonates, and operating characteristics of Rochester Criteria (RC), Yale Observation Scale (YOS) score, and demographics as a low-risk screening tool.

METHODS

Secondary analysis of healthy febrile infants < 60 days old presenting to any of 26 emergency departments in the Pediatric Emergency Care Applied Research Network between December 2008 and May 2013. Of 7334 infants, 1524 met our inclusion criteria of age ≤ 28 days. All had fevers and underwent evaluation for IBI. Receiver operator characteristic (ROC) curve and transparent decision tree analysis were used to determine the applicability of reassuring RC, YOS, and age parameters as an IBI low-risk screening tool.

RESULTS

Of 1524 neonates, 2.9% had bacteremia and 1.5% had meningitis. After applying RC and YOS, 15 neonates were incorrectly identified as low risk for IBI (10 bacteremia, 4 meningitis, 1 bacteremia, and meningitis). Age ≤ 18 days was a statistically significant variable ROC (area under curve 0.63, p < 0.05). Incorporating age > 18 days as low-risk criteria with reassuring RC and YOS misclassified 7 IBI patients (6 bacteremia, 1 meningitis).

CONCLUSION

Thirty percent of febrile neonates met low-risk criteria, age > 18 days, reassuring RC and YOS, and could avoid LP and empiric antibiotics. Our low-risk guidelines may improve patient safety and reduce health care costs by decreasing lab testing for cerebrospinal fluid, empiric antibiotic administration, and prolonged hospitalization. These results are hypothesis-generating and should be verified with a randomized prospective study.

Age- and sex-specific prevalence of serious bacterial infections in febrile infants ≤60 days, in Sweden

AIM

The aim of the study was to describe age- and sex-specific prevalence of serious bacterial infections (SBI: urinary tract infection, bacteraemia, meningitis) among febrile infants ≤60 days in Sweden.

METHODS

This is a retrospective study in 4 Pediatric Emergency Departments from 2014 to 2017, in previously healthy, full-term infants ≤60 days with fever without a source.

RESULTS

Of the 1,701 included infants, 214 (12.6%; 95% CI, 11.1-14.3) had an SBI. Urinary tract infection (UTI) was diagnosed in 196 (11.5%; 95% CI, 10.0-13.1) patients. In the ≤28 and 29-60 days age-groups, meningitis prevalence was 0.9% (95% CI, 0.3-2.0) and 0.3% (95% CI, 0.1-0.8), whereas bacteraemia prevalence was 3.2% (95% CI, 1.9-4.9) and 0.6% (95% CI, 0.2-1.3). The SBI prevalence was higher in boys 16.0% (95% CI, 13.8-18.5) than girls 8.0% (95% CI, 6.2-10.2; p<0.001), due to 2-fold higher UTI risk. The prevalence of meningitis in boys was 0.3% (95% CI, 0.1- 0.9) vs. 0.7% (95% CI, 0.2-1.6) in girls and of bacteraemia 1.8% (95% CI, 1.0-2.8) vs. 1.0% (95% CI, 0.4-2.0), respectively.

CONCLUSIONS

The total SBI prevalence was 12.6%, and UTI represented the vast majority. The prevalence of bacteraemia and meningitis was low, particularly in the 29-60 days age group, without significant difference between boys and girls.

Prevalence of Bacterial Meningitis Among Febrile Infants Aged 29-60 Days With Positive Urinalysis Results: A Systematic Review and Meta-analysis

IMPORTANCE

Fever in the first months of life remains one of the most common pediatric problems. Urinary tract infections are the most frequent serious bacterial infections in this population. All published guidelines and quality initiatives for febrile young infants recommend lumbar puncture (LP) and cerebrospinal fluid (CSF) testing on the basis of a positive urinalysis result to exclude bacterial meningitis as a cause. For well infants older than 28 days with an abnormal urinalysis result, LP remains controversial.

OBJECTIVE

To assess the prevalence of bacterial meningitis among febrile infants 29 to 60 days of age with a positive urinalysis result to evaluate whether LP is routinely required.

DATA SOURCES

MEDLINE and Embase were searched for articles published from January 1, 2000, to July 25, 2018, with deliberate limitation to recent studies. Before analysis, the search was repeated (October 6, 2019) to ensure that new studies were included.

STUDY SELECTION

Studies that reported on healthy, full-term, well-appearing febrile infants 29 to 60 days of age for whom patient-level data could be ascertained for urinalysis results and meningitis status were included.

DATA EXTRACTION AND SYNTHESIS

Data were extracted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and used the Newcastle-Ottawa Scale to assess bias. Pooled prevalences and odds ratios (ORs) were estimated using random-effect models.

MAIN OUTCOMES AND MEASURES

The primary outcome was the prevalence of culture-proven bacterial meningitis among infants with positive urinalysis results. The secondary outcome was the prevalence of bacterial meningitis, defined by CSF testing or suggestive history at clinical follow-up.

RESULTS

The parent search yielded 3227 records; 48 studies were included (17 distinct data sets of 25 374 infants). The prevalence of culture-proven meningitis was 0.44% (95% CI, 0.25%-0.78%) among 2703 infants with positive urinalysis results compared with 0.50% (95% CI, 0.33%-0.76%) among 10 032 infants with negative urinalysis results (OR, 0.74; 95% CI, 0.39-1.38). The prevalence of bacterial meningitis was 0.25% (95% CI, 0.14%-0.45%) among 4737 infants with meningitis status ascertained by CSF testing or clinical follow-up and 0.28% (95% CI, 0.21%-0.36%) among 20 637 infants with positive and negative urinalysis results (OR, 0.89; 95% CI, 0.48-1.68).

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, the prevalence of bacterial meningitis in well-appearing febrile infants 29 to 60 days of age with positive urinalysis results ranged from 0.25% to 0.44% and was not higher than that in infants with negative urinalysis results. These results suggest that for these infants, the decision to use LP should not be guided by urinalysis results alone.

Hypothermia: A Sign of Sepsis in Young Infants in the Emergency Department?

OBJECTIVES

Diagnosis of sepsis in young infants can be challenging due to the nonspecific signs, which can include hypothermia. Whether the presence of hypothermia in young infants should prompt evaluation for serious infection is unclear. The objectives were to measure the prevalence of serious infection among infants ≤60 days of age with hypothermia in the emergency department (ED) and determine other clinical features of hypothermic infants who have serious infection.

METHODS

This is a retrospective analysis of all infants ≤60 days seen in a children's hospital ED from April 2014 to February 2017. Primary outcome was presence of serious infection, defined as urinary tract infection, bacteremia, meningitis, pneumonia, or herpes virus infection. Hypothermia was defined as a rectal temperature of 36.0°C or less.

RESULTS

Of 4797 infants ≤60 days of age seen in the ED, 116 had hypothermia. The prevalence of serious infection was 2.6% (3/116) in hypothermic infants compared with 15.2% (61/401) in febrile infants (P < 0.01). Hypothermic infants with serious infections were more likely to have a history of prematurity, apnea, poor feeding, lethargy, ill-appearance, and respiratory signs than hypothermic infants without serious infection. All 3 hypothermic infants with serious infection had other concerning features.

CONCLUSIONS

The prevalence of serious infection in hypothermic young infants in the ED is low. Serious infection is unlikely in infants with isolated hypothermia.

Fever Without an Apparent Source in Young Infants: A Multicenter Retrospective Evaluation of Adherence to the Dutch Guidelines

BACKGROUND

The Dutch fever without an apparent source (FWS) guidelines were published to timely recognize and treat serious infections. We determined the adherence to the Dutch FWS guidelines and the percentage of serious infections in infants younger than 3 months of age. Second, we identified which clinical criteria, diagnostic tests, and management were associated with nonadherence to the guidelines.

METHODS

A retrospective cohort study was performed in 2 Dutch teaching hospitals. We assessed the charts of all infants with FWS who presented at the emergency departments from September 30, 2017, to October 1, 2019. Diagnostic and therapeutic decisions were compared with the recommendations, as published in the Dutch guidelines. Infants were categorized into the nonadherence group in case 1 or more recommendations were not adhered to.

RESULTS

Data on 231 infants were studied; 51.5% of the cases adhered to the Dutch guidelines and 16.0% suffered from a serious infection. The percentage of infants with a serious infection was higher in the adherence compared with the nonadherence group. We observed no relevant differences in clinical outcomes. Univariate regression analysis showed that an abnormal white blood cell count was associated with nonadherence (OR 0.4, P = 0.049). Not obtaining a urine and blood culture and not starting intravenous antibiotic treatment were the most frequent reasons for nonadherence to the guidelines.

CONCLUSIONS

Our study indicates that there was nonadherence in a large proportion of FWS cases. The guidelines may need to be adjusted to increase adherence.

Management of febrile infants aged 1 month and less than 3 months in a French university hospital: Clinical practice evaluation

BACKGROUND

Management of febrile infants is challenging due to the increased risk of serious bacterial infections and it varies among physicians and hospitals. The goals of this study were to describe and compare the management of febrile infants aged 1-2 months in a hospital in 2011 and 2016.

METHODS

We conducted a retrospective study in the Bordeaux Pellegrin University Hospital, France, in 2011 and 2016. All infants aged 1-2 months with diagnosis codes referring to fever were included. Data on infant characteristics, fever episodes, clinical symptoms, and management were collected from medical charts. Univariate analyses and multivariate logistic models were used.

RESULTS

A total of 530 infants were included; 89.2% had blood testing and 81.1% urine testing; 79.6% of the infants were hospitalized, three of them in the pediatric intensive care unit. The median hospitalization duration was 3 days. In the sample investigated, 59.8% of the infants received antibiotic therapy and 128 (24.1%) had bacterial infections with no difference between 2011 and 2016. The main bacterial infection was pyelonephritis (86.7%). Urethral catheterization was implemented in 2016, whereas a urine bag was utilized for 174 out of 177 infants in 2011. The percentage of contaminated urine cultures was higher in 2011 (35.9%) than in 2016 (19.6%, P<0.001). The hospitalization rate was higher in 2016.

CONCLUSIONS

Management of febrile infants changed between 2011 and 2016. The hospitalization rate and antibiotic therapy use remained high regarding the rate of bacterial infection. Use of urethral catheterization decreased the level of contamination.

Performance of blood biomarkers to rule out invasive bacterial infection in febrile infants under 21 days old

OBJECTIVES

To determine the performance of procalcitonin (PCT), C reactive protein (CRP) and absolute neutrophil count (ANC) in identifying invasive bacterial infection (IBI) among well-appearing infants ≤21 days old with fever without source and no leukocyturia. To compare this performance with that in those 22-90 days old.

DESIGN

Substudy of a prospective single-centre registry performed between September 2008 and August 2017.

SETTING

Paediatric emergency department of a tertiary teaching hospital.

PATIENTS

196 infants ≤21 days old and 1331 infants 22-90 days old.

MAIN OUTCOME MEASURES

Sensitivity and negative likelihood ratio of blood tests for ruling out IBI (positive blood or cerebrospinal fluid culture). Abnormal blood test results: PCT ≥0.5 ng/mL, CRP >20 mg/L and ANC >10 000/µL.

RESULTS

Prevalence of IBI in infants ≤21 days old with normal or any abnormal blood test result was 3.6% and 6.8%, respectively (OR 0.52 (95% CI 0.13 to 2.01)), compared with 0.2% and 4.5% in older infants (OR 0.03 (95% CI 0 to 0.17)). Sensitivity and negative likelihood ratio of the blood tests for ruling out IBI in infants ≤21 days were 44.4% (95% CI 18.9% to 73.3%) and 0.79 (95% CI 0.43 to 1.44), respectively (vs 84.6% (95% CI 57.8% to 95.7%)%) and 0.19 (95% CI 0.05 to 0.67) in older infants). The values improved in infants with fever ≥6 hours aged 22-90 days, but not in those ≤21 days.

CONCLUSIONS

PCT, CRP and ANC are not useful for ruling out IBI in febrile infants ≤21 days old. It is still recommended that these patients are admitted and given empirical antibiotic therapy, regardless of their general appearance or blood test results.

Prevalence of Bacteremia and Bacterial Meningitis in Febrile Neonates and Infants in the Second Month of Life: A Systematic Review and Meta-analysis

IMPORTANCE

Febrile neonates (persons in the first month of life) are believed to be at higher risk for bacteremia or bacterial meningitis than infants in their second month of life. However, the true prevalence is unclear.

OBJECTIVE

To determine modern rates of bacteremia and bacterial meningitis in febrile neonates and infants in the second month of life presenting to an ambulatory setting.

DATA SOURCES

A comprehensive, no-limit search was conducted in PubMed using previously published search terms in February 2015 and repeated in September 2016.

STUDY SELECTION

Abstracts and full texts were reviewed independently by several investigators. Studies were included if data regarding blood cultures or cerebrospinal fluid cultures from consecutive febrile infants in an ambulatory setting could be extrapolated within the age groups. To limit the analysis to the period after the availability of the Haemophilus influenzae type b vaccination, studies that collected data before 1990 were excluded.

DATA EXTRACTION AND SYNTHESIS

Data were extracted in accordance with the Meta-analyses of Observational Studies in Epidemiology (MOOSE) reporting guidelines via independent abstraction by several investigators. The Newcastle-Ottawa Scale was used to assess bias.

MAIN OUTCOMES AND MEASURES

The primary outcomes were prevalence rates of bacteremia and bacterial meningitis in febrile neonates and infants in the second month of life. In neonates, prevalence rates were also estimated in the era of group B Streptococcus intrapartum antibiotic prophylaxis (after 1996).

RESULTS

In total, 7264 abstracts were screened, resulting in 188 full-text manuscripts reviewed, with 12 meeting inclusion criteria (with 15 713 culture results). For febrile neonates, the prevalence of bacteremia was 2.9% (95% CI, 2.3%-3.7%; I2 = 50%; n = 5145) and the prevalence of bacterial meningitis was 1.2% (95% CI, 0.8%-1.9%; I2 = 27%; n = 3288). In neonates in the era after group B Streptococcus prophylaxis, the prevalence of bacteremia was 3.0% (95% CI, 2.3%-3.9%; I2 = 6%; n = 2055) and the prevalence of meningitis was 1.0% (95% CI, 0.4%-2.1%; I2 = 28%; n = 1739). For febrile infants in the second month of life, the prevalence of bacteremia was 1.6% (95% CI, 0.9%-2.7%; I2 = 78%; n = 4778) and the prevalence of meningitis was 0.4% (95% CI, 0.2%-1.0%; I2 = 33%; n = 2502).

CONCLUSIONS AND RELEVANCE

These findings suggest that febrile neonates have approximately twice the rate of bacteremia and meningitis as febrile infants in their second month of life.

Associations of Neighborhood-Level Social Determinants of Health with Bacterial Infections in Young, Febrile Infants

OBJECTIVE

To examine the sociodemographic characteristics of one population of young, febrile infants and identify associations between neighborhood-level social determinants of health (SDHs) with bacterial infections.

STUDY DESIGN

This was a retrospective cross sectional study of all infants ≤90 days old with a temperature of ≥38°C who presented in 2014 to the emergency department of an urban children's hospital in a large east coast city. The primary outcome was the presence of a bacterial infection, defined as a positive urine, blood, or cerebrospinal fluid culture that was treated clinically as a pathogen. The home address of each infant was geocoded and linked to neighborhood data based on census tract. Neighborhood-level SDHs included deprivation index, median household income, poverty, childhood poverty, social capital, and crowded housing. Associations were estimated using generalized estimating equations and negative binomial regression analysis. Models were adjusted for age, prematurity, and race/ethnicity.

RESULTS

Of 232 febrile infants, the median age was 54 days, 58% were male, 49% were Hispanic, and 88% had public health insurance; 31 infants (13.4%) had a bacterial infection. In the adjusted analyses, the risk of bacterial infection among infants from neighborhoods with high rates of childhood poverty was >3 times higher (relative risk, 3.16; 95% CI, 1.04-9.6) compared with infants from neighborhoods with low rates of childhood poverty.

CONCLUSIONS

Our findings suggest that SDHs may be associated with bacterial infections in young, febrile infants. If confirmed in subsequent studies, the inclusion of SDHs in predictive tools may improve accuracy in detecting bacterial infections among young, febrile infants.

Clinical prediction models for young febrile infants at the emergency department: an international validation study

OBJECTIVE

To assess the diagnostic value of existing clinical prediction models (CPM; ie, statistically derived) in febrile young infants at risk for serious bacterial infections.

METHODS

A systematic literature review identified eight CPMs for predicting serious bacterial infections in febrile children. We validated these CPMs on four validation cohorts of febrile children in Spain (age <3 months), France (age <3 months) and two cohorts in the Netherlands (age 1-3 months and >3-12 months). We evaluated the performance of the CPMs by sensitivity/specificity, area under the receiver operating characteristic curve (AUC) and calibration studies.

RESULTS

The original cohorts in which the prediction rules were developed (derivation cohorts) ranged from 381 to 15 781 children, with a prevalence of serious bacterial infections varying from 0.8% to 27% and spanned an age range of 0-16 years. All CPMs originally performed moderately to very well (AUC 0.60-0.93). The four validation cohorts included 159-2204 febrile children, with a median age range of 1.8 (1.2-2.4) months for the three cohorts <3 months and 8.4 (6.0-9.6) months for the cohort >3-12 months of age. The prevalence of serious bacterial infections varied between 15.1% and 17.2% in the three cohorts <3 months and was 9.8% for the cohort >3-12 months of age. Although discriminative values varied greatly, best performance was observed for four CPMs including clinical signs and symptoms, urine dipstick analyses and laboratory markers with AUC ranging from 0.68 to 0.94 in the three cohorts <3 months (ranges sensitivity: 0.48-0.94 and specificity: 0.71-0.97). For the >3-12 months' cohort AUC ranges from 0.80 to 0.89 (ranges sensitivity: 0.70-0.82 and specificity: 0.78-0.90). In general, the specificities exceeded sensitivities in our cohorts, in contrast to derivation cohorts with high sensitivities, although this effect was stronger in infants <3 months than in infants >3-12 months.

CONCLUSION

We identified four CPMs, including clinical signs and symptoms, urine dipstick analysis and laboratory markers, which can aid clinicians in identifying serious bacterial infections. We suggest clinicians should use CPMs as an adjunctive clinical tool when assessing the risk of serious bacterial infections in febrile young infants.

Invasive bacterial infections in young afebrile infants with a history of fever

OBJECTIVE

To determine the prevalence of invasive bacterial infections (IBI, pathogenic bacteria in blood or cerebrospinal fluid) in infants less than 90 days old with fever without a source related to the presence or absence of fever on arrival to the emergency department (ED).

DESIGN

Prospective registry-based cohort study.

SETTING

Paediatric ED of a tertiary teaching hospital.

PATIENTS

We included infants less than 90 days old with a history of fever evaluated in the ED from 2003 to 2016.

MAIN OUTCOMES AND MEASURES

The prevalence of IBI in patients with a history of fever who were febrile and afebrile on arrival to the ED.

RESULTS

We included 2470 infants: 678 afebrile and 1792 febrile when evaluated in the ED. Fifty-nine (2.4%) were diagnosed with an IBI (bacteraemia 46, meningitis 7 and sepsis 6): 16 in the group of afebrile infants with a history of fever (2.4%, 95% CI 1.4 to 3.8 vs 43 in the febrile group, 2.4%, 95% CI 1.8 to 3.2). Of the 16 afebrile infants with a history of fever diagnosed with an IBI, 14 were well appearing. The rate of non-IBI (pathogenic bacteria in urine or stools) was similar in both groups (15.5% and 16.7%).

CONCLUSIONS

The prevalence of IBI in infants ≤90 days with a history of fever is similar regardless of the presence of fever on the arrival at the ED. The approach to infants with a history of fever who are afebrile in the ED should not differ from that recommended for infants who are febrile in the ED.

Serious Bacterial Infections in Hospitalized Febrile Infants in the First and Second Months of Life

OBJECTIVE

Most protocols evaluating serious bacterial infection (SBI) risk in febrile infants classify neonates <30 days of age as high risk (HR), while other protocols do not distinguish between infants <30 and 30-60 days of age. We compared SBI rates in febrile infants at the first and the second months of life.

METHODS

This was a retrospective, population-based, cohort study. All febrile infants ≤60 days of age hospitalized in southern Israel, January 2013 through May 2014, were included. SBI risk assessment included medical history, physical examination, blood count and dipstick urine analysis.

RESULTS

Overall, 623 infants were identified; 142 HR infants <30 days of age, 95 low-risk (LR) infants <30 days of age, 232 HR infants 30-60 days of age and 154 LR infants 30-60 days of age. Urinary tract infection comprised 84.7% (133/157) of all SBIs. Among HR infants, higher SBI rates were observed in <30 versus 30-60 days (45.0% vs. 29.3%; P = 0.003), while respective rates were similar among LR infants (8.4% vs. 11.0%; P = 0.66). SBI rates in HR infants 0-14 versus 15-60 days of age were 45.3% versus 33.6% (P = 0.12), and 19.2% versus 8.9% (P = 0.15) in LR infants. Among HR infants, SBI rates were 52.8% and 39.5% in infants <30 days of age with temperature ≥39°C and <39°C, respectively, while in infants ≥30 days of age, respective rates were 31.2% and 26.7% (P = 0.005, comparing the 4 groups). Among LR infants, rates were not affected by temperature degree. Thrombocytopenia was associated with higher SBI rates in HR, but not in LR.

CONCLUSIONS

In HR infants, higher SBI rates were associated with younger age, higher body temperature and thrombocytopenia. In contrast, SBI (mostly urinary tract infection) rates among LR infants (approximately 10%) were not associated with these factors.

Prevalence of Concomitant Acute Bacterial Meningitis in Neonates with Febrile Urinary Tract Infection: A Retrospective Cross-Sectional Study

OBJECTIVE

To describe the frequency of concomitant acute bacterial meningitis (ABM) in neonates with febrile urinary tract infection (UTI).

STUDY DESIGN

This was a retrospective cross-sectional study from 2005 to 2013 of infants ≤30 days old evaluated in the emergency department of a quaternary care children's hospital with fever and laboratory-confirmed UTI. Definite ABM was defined as cerebrospinal fluid (CSF) culture with growth of pathogenic bacteria and probable ABM if pleocytosis with ≥ 20 white blood cell was present in an antibiotic-pretreated patient. The timing of lumbar puncture and first antibiotic dose was recorded to assess for antibiotic pretreatment.

RESULTS

A total of 236 neonates with UTI were included. Mean age was 18.6 days (SD 6.2); 79% were male infants. Twenty-three (9.7%) had bacteremia. Fourteen (6%) were pretreated. No neonate (0%; 95% CI 0%-1.6%) had definite ABM and 2 (0.8%; 95% CI 0.1%-3.0%) neonates with bloody CSF had probable ABM. CSF white blood cell count was 25 and 183 for these 2 infants, and CSF red blood cell count was 3100 and 61 932, respectively. Another neonate had herpes simplex virus meningoencephalitis.

CONCLUSIONS

The frequency of ABM in neonates with febrile UTI is low. Further prospective studies are needed to evaluate the safety of a tiered approach to evaluate for serious bacterial infection, in which lumbar puncture potentially could be avoided in well-appearing febrile neonates with suspected UTI.

Outpatient management of selected young febrile infants without antibiotics

OBJECTIVE

To analyse the outpatient management of selected febrile infants younger than 90 days without systematic lumbar puncture and antibiotics.

METHODS

A prospective registry-based cohort study including all the infants ≤90 days with fever without a source (FWS) who were evaluated in a paediatric emergency department (ED) over a 7-year period (September 2007-August 2014). We analysed the outcome of those infants with low-risk criteria for serious bacterial infection (SBI) managed as outpatients without antibiotics and without undergoing a lumbar puncture. Low-risk criteria: Well appearing, older than 21 days of age, no leucocyturia, absolute neutrophil count ≤10 000, serum C reactive protein ≤20 mg/L, procalcitonin <0.5 ng/mL and no clinical deterioration during the stay in the ED (always <24 hours).

RESULTS

1472 infants with FWS attended the ED. Of these, 676 were classified to be at low risk for SBI without performing a lumbar puncture. After staying <24 hours in the short-stay unit of the ED, 586 (86.6%) were managed as outpatients without antibiotics. Two patients were diagnosed with SBI: one occult bacteraemia and one bacterial gastroenteritis. Both were afebrile when evaluated again and did well. No patient returned to the ED due to clinical deterioration. Fifty-one infants (8.7%) returned to the ED mainly due to persistence of fever or irritability. None was diagnosed with definite SBI or non-bacterial meningitis.

CONCLUSIONS

Outpatient management without antibiotics and systematic lumbar puncture is appropriate for selected febrile infants younger than 3 months of age with close follow-up.

Importance of Urine Dipstick in Evaluation of Young Febrile Infants With Positive Urine Culture: A Spanish Pediatric Emergency Research Group Study

BACKGROUND AND OBJECTIVES

Guidelines from the American Academy of Pediatrics define urinary tract infection (UTI) as the growth of greater than 50,000 ufc/mL of a single bacterium in a urine culture with a positive urine dipstick or with a urinalysis associated. Our objective was to evaluate the adequacy of this cutoff point for the diagnosis of UTI in young febrile infants.

METHODS

Subanalysis of a prospective multicenter study developed in RISeuP-SPERG Network between October 11 and September 13. To carry out the study, it was performed a comparison of analytical and microbiological characteristics of patients younger than 90 days with fever without focus, taking into account the results of urine dipstick and urine culture.

RESULTS

Of a total of 3333 infants younger than 90 days with fever without focus which were included in the study, 538 were classified as UTI in accordance with American Academy of Pediatrics' guidelines. These patients were similar to those who had a positive urine dipstick and a urine culture yielding of 10,000 to 50,000 ufc/mL, and they were different from those who had a normal urine dipstick and a urine culture >50,000 ufc/mL, being focused on the isolated bacteria and blood biomarkers values. Forty-five invasive bacterial infections were diagnosed (5.9% of the 756 with a urine culture >10,000 ufc/mL). Half of the infants with a normal urine dipstick diagnosed with invasive bacterial infections were younger than 15 days.

CONCLUSIONS

It might be inadequate to use a threshold of 50,000 cfu/mL to consider a urine culture as positive in young febrile infants given the fact that it would misdiagnose several UTIs.

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

BACKGROUND

A sequential approach to young febrile infants on the basis of clinical and laboratory parameters, including procalcitonin, was recently described as an accurate tool in identifying patients at risk for invasive bacterial infection (IBI). Our aim was to prospectively validate the Step-by-Step approach and compare it with the Rochester criteria and the Lab-score.

METHODS

Prospective study including infants ≤90 days with fever without source presenting in 11 European pediatric emergency departments between September 2012 and August 2014. The accuracy of the Step-by-Step approach, the Rochester criteria, and the Lab-score in identifying patients at low risk of IBI (isolation of a bacterial pathogen in a blood or cerebrospinal fluid culture) was compared.

RESULTS

Eighty-seven of 2185 infants (4.0%) were diagnosed with an IBI. The prevalence of IBI was significantly higher in infants classified as high risk or intermediate risk according to the Step by Step than in low risk patients. Sensitivity and negative predictive value for ruling out an IBI were 92.0% and 99.3% for the Step by Step, 81.6% and 98.3% for the Rochester criteria, and 59.8% and 98.1% for the Lab-score. Seven infants with an IBI were misclassified by the Step by Step, 16 by Rochester criteria, and 35 by the Lab-score.

CONCLUSIONS

We validated the Step by Step as a valuable tool for the management of infants with fever without source in the emergency department and confirmed its superior accuracy in identifying patients at low risk of IBI, compared with the Rochester criteria and the Lab-score.

Accuracy of diagnosis codes to identify febrile young infants using administrative data

BACKGROUND

Administrative data can be used to determine optimal management of febrile infants and aid clinical practice guideline development.

OBJECTIVE

Determine the most accurate International Classification of Diseases, Ninth Revision (ICD-9) diagnosis coding strategies for identification of febrile infants.

DESIGN

Retrospective cross-sectional study.

SETTING

Eight emergency departments in the Pediatric Health Information System.

PATIENTS

Infants aged <90 days evaluated between July 1, 2012 and June 30, 2013 were randomly selected for medical record review from 1 of 4 ICD-9 diagnosis code groups: (1) discharge diagnosis of fever, (2) admission diagnosis of fever without discharge diagnosis of fever, (3) discharge diagnosis of serious infection without diagnosis of fever, and (4) no diagnosis of fever or serious infection.

EXPOSURE

The ICD-9 diagnosis code groups were compared in 4 case-identification algorithms to a reference standard of fever ≥100.4°F documented in the medical record.

MEASUREMENTS

Algorithm predictive accuracy was measured using sensitivity, specificity, and negative and positive predictive values.

RESULTS

Among 1790 medical records reviewed, 766 (42.8%) infants had fever. Discharge diagnosis of fever demonstrated high specificity (98.2%, 95% confidence interval [CI]: 97.8-98.6) but low sensitivity (53.2%, 95% CI: 50.0-56.4). A case-identification algorithm of admission or discharge diagnosis of fever exhibited higher sensitivity (71.1%, 95% CI: 68.2-74.0), similar specificity (97.7%, 95% CI: 97.3-98.1), and the highest positive predictive value (86.9%, 95% CI: 84.5-89.3).

CONCLUSIONS

A case-identification strategy that includes admission or discharge diagnosis of fever should be considered for febrile infant studies using administrative data, though underclassification of patients is a potential limitation.

Association of clinical practice guidelines with emergency department management of febrile infants ≤56 days of age

BACKGROUND

Differences among febrile infant institutional clinical practice guidelines (CPGs) may contribute to practice variation and increased healthcare costs.

OBJECTIVE

Determine the association between pediatric emergency department (ED) CPGs and laboratory testing, hospitalization, ceftriaxone use, and costs in febrile infants.

DESIGN

Retrospective cross-sectional study in 2013.

SETTING

Thirty-three hospitals in the Pediatric Health Information System.

PATIENTS

Infants aged ≤56 days with a diagnosis of fever.

EXPOSURES

The presence and content of ED-based febrile infant CPGs assessed by electronic survey.

MEASUREMENTS

Using generalized estimating equations, we evaluated the association between CPG recommendations and rates of urine, blood, cerebrospinal fluid (CSF) testing, hospitalization, and ceftriaxone use at ED discharge in 2 age groups: ≤28 days and 29 to 56 days. We also assessed CPG impact on healthcare costs.

RESULTS

We included 9377 ED visits; 21 of 33 EDs (63.6%) had a CPG. For neonates ≤28 days, CPG recommendations did not vary and were not associated with differences in testing, hospitalization, or costs. Among infants 29 to 56 days, CPG recommendations for CSF testing and ceftriaxone use varied. CSF testing occurred less often at EDs with CPGs recommending limited testing compared to hospitals without CPGs (adjusted odds ratio: 0.5, 95% confidence interval: 0.3-0.8). Ceftriaxone use at ED discharge varied significantly based on CPG recommendations. Costs were higher for admitted and discharged infants 29 to 56 days old at hospitals with CPGs.

CONCLUSIONS

CPG recommendations for febrile infants 29 to 56 days old vary across institutions for CSF testing and ceftriaxone use, correlating with observed practice variation. CPGs were not associated with lower healthcare costs.

Comparison of pediatric and general emergency medicine practice patterns in infants with fever

OBJECTIVES

To evaluate and compare the management approaches of pediatric and general emergency medicine physicians in infants presenting to the emergency department (ED) with complaint of fever.

METHODS

Infants 90 days of age or younger with a chief complaint of fever were included for review. Vital signs, laboratory workup, disposition, and final diagnosis were collected. Compliance with guidelines was assessed and compared between EDs.

RESULTS

Compliance with admission guidelines was not significantly different in any of the 3 age groups evaluated between the pediatric and general ED (PED and GED). Compliance with guideline recommendations for laboratory workup was not significantly different between the 2 EDs, nor was overall compliance with guideline recommendations.

CONCLUSIONS

No significant variations in the management of febrile infants or compliance with published guidelines between PED and GED physicians were observed. Young infants can be safely treated for fever in the PED or GED.

Management of febrile neonates in US pediatric emergency departments

BACKGROUND

Blood, urine, and cerebrospinal fluid cultures and admission for antibiotics are considered standard management of febrile neonates (0-28 days). We examined variation in adherence to these recommendations across US pediatric emergency departments (PEDs) and incidence of serious infections (SIs) in febrile neonates.

METHODS

Cross-sectional study of neonates with a diagnosis of fever evaluated in 36 PEDs in the 2010 Pediatric Health Information System database. We analyzed performance of recommended management (laboratory testing, antibiotic use, admission to hospital), 48-hour return visits to PED, and diagnoses of SI.

RESULTS

Of 2253 neonates meeting study criteria, 369 (16.4%) were evaluated and discharged from the PED; 1884 (83.6%) were admitted. Recommended management occurred in 1497 of 2253 (66.4%; 95% confidence interval, 64.5-68.4) febrile neonates. There was more than twofold variation across the 36 PEDs in adherence to recommended management, recommended testing, and recommended treatment of febrile neonates. There was significant variation in testing and treatment between admitted and discharged neonates (P < .001). A total of 269 in 2253 (11.9%) neonates had SI, of whom 223 (82.9%; 95% confidence interval, 77.9-86.9) received recommended management.

CONCLUSIONS

There was wide variation across US PEDs in adherence to recommended management of febrile neonates. One in 6 febrile neonates was discharged from the PED; discharged patients were less likely to receive testing or antibiotic therapy than admitted patients. A majority of neonates with SI received recommended evaluation and management. High rates of SI in admitted patients but low return rates for missed infections in discharged patients suggest a need for additional studies to understand variation from the current recommendations.

Accuracy of a sequential approach to identify young febrile infants at low risk for invasive bacterial infection

INTRODUCTION

Much effort has been put in the past years to create and assess accurate tools for the management of febrile infants. However, no optimal strategy has been so far identified. A sequential approach evaluating, first, the appearance of the infant, second, the age and result of the urinanalysis and, finally, the results of the blood biomarkers, including procalcitonin, may better identify low risk febrile infants suitable for outpatient management.

OBJECTIVE

To assess the value of a sequential approach ('step by step') to febrile young infants in order to identify patients at a low risk for invasive bacterial infections (IBI) who are suitable for outpatient management and compare it with other previously described strategies such as the Rochester criteria and the Lab-score.

METHODS

A retrospective comparison of three different approaches (step by step, Lab-score and Rochester criteria) was carried out in 1123 febrile infants less than 3 months of age attended in seven European paediatric emergency departments. IBI was defined as isolation of a bacterial pathogen from the blood or cerebrospinal fluid.

RESULTS

Of the 1123 infants (IBI 48; 4.2%), 488 (43.4%) were classified as low-risk criteria according to the step by step approach (vs 693 (61.7%) with the Lab-score and 458 (40.7%) with the Rochester criteria). The prevalence of IBI in the low-risk criteria patients was 0.2% (95% CI 0% to 0.6%) using the step by step approach; 0.7% (95% CI 0.1% to 1.3%) using the Lab-score; and 1.1% (95% CI 0.1% to 2%) using the Rochester criteria. Using the step by step approach, one patient with IBI was not correctly classified (2.0%, 95% CI 0% to 6.12%) versus five using the Lab-score or Rochester criteria (10.4%, 95% CI 1.76% to 19.04%).

CONCLUSIONS

A sequential approach to young febrile infants based on clinical and laboratory parameters, including procalcitonin, identifies better patients more suitable for outpatient management.