Correlation between locally versus centrally processed serum procalcitonin during emergency department research evaluation of febrile infants aged 0-60 days.

Introduction: Procalcitonin (PCT) is a useful biomarker in the initial evaluation of febrile infants for serious bacterial infections (SBIs). However, PCT is not always available locally and must at times be frozen and shipped to a reference laboratory for research studies. We sought to compare PCT measured locally versus centrally at a reference laboratory during a research study. Materials and methods: This was a secondary analysis of a multicenter study of febrile infants ≤60 days evaluated for SBIs from June 2016 to April 2019. A PCT cutoff value of 0.5 ng/mL was used to stratify infants at low-versus high-risk of SBIs. Statistical analyses consisted of Spearman's correlation, Bland-Altman difference plotting, Passing-Bablok regression, Deming regression, and Fisher's exact testing at the 0.5 ng/mL threshold. Results: 241 febrile infants had PCT levels measured both locally and at the reference laboratory. PCT levels measured locally on 5 different platforms and from the frozen research samples demonstrated strong Spearman's correlation (ρ = 0.83) and had similar mean PCT values with an average relative difference of 0.02%. Eleven infants with SBIs had PCT values < 0.5 ng/mL in both the clinical and research samples. Six other infants had differences in SBI prediction based on PCT values at the 0.5 ng/mL threshold between the clinical and research platforms. Conclusions: We found no significant differences in detection of febrile infants at high risk for SBI based on locally (on multiple platforms) versus centrally processed PCT. Testing at a central reference laboratory after freezing and shipping is an accurate and reliable alternative for research studies or when rapid turnaround is not required.

Clinical Course, Laboratory Findings, and Prognosis of SARS-CoV-2 Infection in Infants up to 90 Days of Age: A Single-Center Experience and a Proposal for a Management Pathway.

AIM: To provide a comprehensive description of the clinical features, biochemical characteristics, and outcomes of infants up to 90 days old with COVID-19. Moreover, to assess the severity of the disease and propose an effective management pathway. METHODS: Retrospective single-center study spanning three years. Patient data includes age, sex, symptoms, comorbidities, blood and urine test results, cultures, admission, length of stay, therapies, intensive care unit admission, and mortality. RESULTS: A total of 274 patients were enrolled in the study, comprising 55% males. Among them, 60 patients (22%) were under the age of 29 days, while 214 (78%) fell within the 29 to 90 days age range. The overall incidence of SARS-CoV-2 infections was 0.28 per 10,000 Pediatric Emergency Department admissions. Blood inflammatory markers showed no significant abnormalities, and there were no recorded instances of positive blood cultures. Less than 1% of infants showed urinary tract infections with positive urine cultures, and 1.5% of patients had a concurrent RSV infection. Hospitalization rates were 83% for neonates and 67% for infants, with a median length of stay (LOS) of 48 h for both age groups. None of the patients required admission to the Pediatric or Neonatal Intensive Care Unit, and only one required High Flow Nasal Cannula (HFNC). No secondary serious bacterial infections were observed, and all hospitalized patients were discharged without short-term sequelae. No deaths were reported. DISCUSSION AND CONCLUSIONS: Infants with COVID-19 generally exhibit milder or asymptomatic forms of the disease, making home management a viable option in most cases. Blood tests, indicative of a mild inflammatory response, are recommended primarily for children showing symptoms of illness. Hospitalization precautions for infants without apparent illness or comorbidities are deemed unnecessary. Given the evolving nature of experiences with COVID-19 in infants, maintaining a high level of clinical suspicion remains imperative.

Proportion of Successful Lumbar Punctures in Infants Younger Than Three Months.

It is important to perform lumbar punctures (LPs) without a single traumatic tap in infants younger than three months owing to the risk of serious complications. The proportion of LPs in which clear cerebrospinal fluid (CSF) was obtained has been previously reported, but some of the procedures involved a traumatic tap. The present study aimed to identify the proportion of LPs in which clear CSF was obtained without a single traumatic tap and the factors associated with successful LPs in infants younger than three months. This retrospective, observational study included children younger than three months who underwent an LP in the pediatric emergency department between April 2018 and March 2021. The primary outcome was the proportion of successful LPs, defined as LPs obtaining clear CSF without a single traumatic tap. Multiple logistic regression analysis was used to identify factors related to successful LPs. Of 126 eligible patients, 121 were included. Among these, 83 (69%) were in the successful group. No factors significantly associated with successful LPs were found. Larger studies based on an accurate definition of successful LPs, such as that provided by this study, are needed to investigate related factors to increase the rate of successful LPs in this age group.

Conundrums in the Management of Febrile Infants under Three Months of Age and Future Research.

Febrile infants under three months of age pose a diagnostic challenge to clinicians. Unlike in older children, the rates of invasive bacterial infections (IBIs), such as bacteraemia or meningitis, are high. This greater risk of IBI combined with the practical challenges of assessing young infants results in a cautious approach with many febrile infants receiving parenteral antibiotics "just in case". However, there is a range of validated tailored care guidelines that support targeted investigation and management of febrile infants, with a cohort identified as lower risk suitable for fewer invasive procedures and observation without parenteral antibiotics. This manuscript outlines five common conundrums related to the safe application of tailored-care guidelines for the assessment and management of febrile infants under three months of age. It also explores future research which aims to further refine the management of febrile infants.

Close Canine Contact: A Case of Infantile Pasteurella Meningitis.

This case report presents an interesting and rare cause of meningitis in young infants, Pasteurella multocida. Not only is the organism unusual but the well appearance of the infant made this diagnosis surprising. The 2021 American Academy of Pediatrics (AAP) clinical practice guidelines on well-appearing febrile infants brought a national guideline on the evaluation and management of fever in infants. However, providers should be aware that there is room for shared decision-making and that the guideline will miss a very small percentage of well-appearing infants with invasive bacterial infections.

Visceral Leishmaniasis (Kala-Azar): A Triumph Against a Trickster Disease.

Leishmaniasis, a protozoan parasitic pathology, is caused by infection with a parasite known as Leishmania donovani, which is transmitted to humans through the bite of a sand fly. The disease has various manifestations, including cutaneous leishmaniasis, visceral leishmaniasis (VL), and disseminated cutaneous leishmaniasis. Visceral leishmaniasis (VL), also known as kala-azar, is mostly seen in the Asian and African regions and can be deadly if left untreated. We present the case of a 10-month-old male infant who was brought to the office with the chief complaints of recurrent fever for the past one month, along with generalized fatigue and poor feeding. A comprehensive history, detailed physical examination, and laboratory testing, including bone marrow aspiration, were performed, and visceral leishmaniasis was diagnosed.

Paediatric emergency departments should manage young febrile and afebrile infants the same if they have a fever before presenting.

AIM: Our aim was to evaluate the risk of bacterial meningitis, bacteremia, and urinary tract infection (UTI) in infants ≤60 days who presented to paediatric emergency departments (PEDs) after having fever at home. We also investigated any differences between infants who were afebrile or febrile on presentation. METHODS: This was a multicenter retrospective study of infants ≤60 days presented to four Swedish PEDs during 2014-2020 with reported fever at home. We used relative risks (RR) to compare the prevalence of UTI, bacteremia, and bacterial meningitis between the infants who were afebrile and the infants who were still febrile when they presented to the PED. RESULTS: The cohort comprised 1926 infants, and 702 (36%) were afebrile on presentation. The prevalence of UTI in the afebrile and febrile infants was 6.1% [95% confidence interval (CI) 4.5-8.2] versus 14.2% (95% CI 12.3-16.2), corresponding to an RR of 0.43 (95% CI 0.31-0.59). In infants ≤28 days, the RR for meningitis was 1.05 (95% CI 0.18-6.23) for afebrile versus febrile infants. Five times more febrile infants underwent a lumbar puncture. CONCLUSION: Infants who were afebrile on presentation underwent fewer lumbar punctures, but they had similar rates of bacterial meningitis to febrile infants. Different management approaches are not justified.

Infrared thermometers and infants: The device is hot the baby maybe not.

AIM: The risk of serious illness in febrile infants (<60 days old) is high, and so fever often warrants aggressive management. Infrared thermometers are unreliable in young infants despite their ubiquity. We aim to describe the: (i) frequency of infrared thermometer usage; (ii) progression to documented fever in the emergency department (ED) and (iii) rate of serious illness (meningitis, urinary tract infection and bacteremia). METHODS: In this single-centre retrospective chart review at The Royal Children's Hospital, Melbourne, we audited medical records of infants (<60 days old) presenting to the ED with pre-hospital fever on history over a 12-month period. We described the type of thermometer used at home (tympanic or forehead, 'infrared' vs. axillary or rectal, 'direct') correlated to peak temperature in ED, investigations, treatment and diagnosis. The primary outcome was subsequent fever in ED. RESULTS: Of 159 infants, two of three had infrared temperature measurement at home. Fifty-one (32.1%) developed fever in ED (direct 28/54, 52% vs. infrared 23/105, 22% RR 2.36 (95% CI 1.52-3.69)). Investigations (75%) and admission (60%) were common. Pre-hospital fever alone was less likely to be associated with serious illness, with fever in ED a much stronger predictor. CONCLUSIONS: In young infants, infrared thermometer use is common and less likely to predict subsequent fever. Twenty-two percent of infants with fever via infrared measurement had fever in ED. History of fever without confirmation is less likely to signal serious illness. Education to public and health-care providers is required to avoid usage of infrared devices in this population.

Contribution of Rapid Influenza Antigen Test to Management of Febrile Young Infants without a Focus.

BACKGROUND: The aim of this study was to evaluate the application of the rapid influenza antigen test and the contribution of the test result to patient management in febrile infants aged 29‒90 days. METHODS: The medical records of febrile infants without a focus who presented during influenza seasons from 2017‒2019 were analyzed retrospectively. The study was carried out in the Department of Pediatric Emergency, Dr. Sami Ulus Maternity and Children's Training and Research Hospital. The demographic characteristics, clinical and laboratory findings, and management of the patients were examined. The patients were divided into two groups as 'with' and 'without' testing based on whether a rapid influenza antigen test was performed or not. Test results were categorized as positive or negative. Serious bacterial infection (SBI) risk and patient management were evaluated according to test results. RESULTS: A total of 173 patients (110 males/63 females) were evaluated. The influenza test was performed in 94 (54.3%) patients, and 31.9% were positive. SBI was present in 8.7% of all patients. The mean values of white blood cell (WBC), absolute neutrophil, platelet count, C-reactive protein (CRP) and, lumbar puncture, hospitalization, and initiation of antibiotic therapy were significantly lower in the positive group compared to the negative and without testing groups (P<0.05). CONCLUSION: This study showed that using the influenza test in the emergency department in young febrile infants significantly reduced the use of antibiotics, hospitalization and the implementation of invasive procedures such as lumbar puncture, and the risk of SBI was not increased.

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.

Clinical utility of procalcitonin in febrile infants younger than 3 months of age visiting a pediatric emergency room: a retrospective single-center study.

BACKGROUND: Fever in infants under 90 days of age is highly likely to be caused by a severe bacterial infection (SBI) and it accounts for a large number of patients visiting the pediatric emergency room. In order to predict the bacterial infection and reduce unnecessary treatment, the classic classification system is based on white blood cell (WBC) count, urinalysis, and x-ray, and it is modified and applied at each center by incorporating recently studied biomarkers such as c-reactive protein (CRP) or procalcitonin (PCT). This study analyzed the usefulness of PCT in predicting SBI when applied along with the existing classification system, including CRP, among infants less than 90 days old who visited with a fever at a single institution pediatric emergency center. METHODS: We retrospectively reviewed the medical records of patients younger than 3 months of age who presented with fever at the Seoul Asan Medical Center pediatric emergency room between July 2017 and October 2018. RESULTS: A total of 317 patients were analyzed, and 61 were diagnosed with SBI, among which urinary tract infection (UTI) accounted for the largest proportion (55/61, 90.2%). There were differences in WBC, neutrophil proportion, CRP, and PCT between the SBI group and the non-SBI group, and the AUC values of WBC, CRP, and PCT were 0.651, 0.804, and 0.746, respectively. When using the cut-off values of CRP and PCTs as 2.0 mg/dL and 0.3 ng/mL, respectively, the sensitivity and specificity for SBI were 49.2/89.5, and 54.1/87.5, respectively. WBC, CRP, and PCT were statistically significant for predicting SBI in multivariate analysis (odds ratios 1.066, 1.377, and 1.291, respectively). When the subjects were classified using the existing classification criteria, WBC and CRP, the positive predictive value (PPV) and negative predictive value (NPV) were 29.3 and 88.7%, respectively, and when PCT was added, the PPV and NPV were 30.7 and 92%, respectively, both increased. CONCLUSION: PCT is useful for predicting SBI in children aged 3 months or less who visit the emergency room with a fever. It is useful as a single biomarker, and when used in conjunction with classic biomarkers, its diagnostic accuracy is further increased.

The prevalence of serious bacterial infections in neutropenic immunocompetent febrile children.

CONTEXT: Febrile neutropenic immunocompromised children are at a high risk of Serious Bacterial Infections (SBI). OBJECTIVE: This systematic review and meta-analysis report the prevalence of SBI in healthy children with febrile neutropenia. DATA SOURCE: PubMed, EMBASE, and Web of Science from their inception to August 2020. STUDY SELECTION: Patients with an Absolute Neutrophil Count (ANC) <1000 cells/mm3 up to 18 years of age presenting to the ED with a chief complaint of fever (temperature > 38°C) and who had a workup for SBI as defined by each study. DATA ABSTRACTION: Data from individual studies was abstracted by a subset of the authors and checked independently by the senior author. Any discrepancies were adjudicated by the joint agreement of all the authors. We calculated the prevalence of SBI by using the number of SBI's as the numerator and the total number of febrile events in patients as the denominator. Bias in our studies was quantified by the Newcastle Ottawa Scale. RESULTS: We identified 2066 citations of which five studies (1693 patients) our inclusion criteria. None of our reviewed studies consistently tested every included patient for SBI. Spectrum bias in every study resulted in a wide range of the SBI prevalence of 1.9% (<0.01% - 11%) similar to non-neutropenic children. LIMITATIONS: All of our studies were retrospective and many did not consistently screen all subjects for SBI. CONCLUSION: If the clinical suspicion is low, the risk for SBI is similar between febrile healthy neutropenic and non-neutropenic children.

Outcomes of Young Infants with Hypothermia Evaluated in the Emergency Department.

OBJECTIVE: To assess the prevalence of serious infections and mortality among infants ≤90 days of age presenting to the emergency department with hypothermia. STUDY DESIGN: We performed a cross-sectional cohort study of infants ≤90 days presenting to any of 40 EDs in the Pediatric Health Information Systems between January 1, 2009, and December 31, 2018. Infants with an International Classification of Diseases, ninth or tenth edition, admission/discharge diagnosis code of hypothermia were included. We determined the prevalence of serious bacterial infection (urinary tract infection, bacteremia, and/or bacterial meningitis), pneumonia, herpes simplex virus (HSV) infection, and emergency department/hospital mortality. RESULTS: We included 3565 infants (1633 male [50.9%] and 3225 ≤30 days of age [90.5%]). Most (65.0%) presented in the first week of life. There were 389 infants (10.8%) with a complex chronic condition. The prevalence of serious bacterial infection was 8.0% (n = 284), including 2.4% (n = 87) with urinary tract infection, 5.6% (n = 199) with bacteremia, and 0.3% (n = 11) with bacterial meningitis. There were 7 patients (0.2%) with neonatal HSV and 9 (0.3%) with pneumonia; 0.2% (n = 6) died. The presence of a complex chronic condition was associated with the presence of serious bacterial infection (P < .001) and was present in 3 of 6 patients who died. In a sensitivity analysis including patients with any diagnosis code of hypothermia (n = 8122), 14.9% had serious bacterial infection, 0.6% had HSV, and 3.3% had pneumonia; 2.0% died. CONCLUSIONS: Of infants with hypothermia ≤90 days of age, 8.3% had serious bacterial infections or HSV. Compared with literature from febrile infants, hypothermia is associated with a high mortality rate. Complex chronic conditions were particularly associated with poor outcomes. Additional research is required to risk stratify young infants with hypothermia.

Automated Versus Manual Band Counts for the Diagnosis of Invasive Bacterial Infections in Infants Who Are Febrile.

We conducted a secondary analysis of a prospective study of infants ≤60 days of age who were febrile to assess the diagnostic accuracy of automated vs manual immature neutrophils for invasive bacterial infections. Although manual counts were superior compared with automated counts, bands had suboptimal accuracy overall and had significant variability in test characteristics based on methodology.

A positive nitrite test was an independent risk factor for invasive bacterial infections in infants under 90 days of age with fever without source.

AIM: This study analysed the association between a positive nitrite dipstick test and an invasive bacterial infection (IBI) in infants younger than 90 days of age with fever without source (FWS). METHODS: We performed a secondary analysis of data from a prospective multicentre study of infants up to 90 days of age with FWS undergoing care in 19 paediatric EDs between October 2011 and September 2013. Invasive bacterial infection was defined as a positive blood or cerebrospinal fluid culture. RESULTS: The dipstick urinalysis was positive for nitrite or leucocyte esterase in 766 (22.5%) of the 3401 infants we studied, and 270 (35.2%) had a dipstick test that was just positive for nitrite. Overall, 107 were diagnosed with an IBI (3.1%). The IBI prevalence was 2.2% among patients with a normal urine dipstick, 4.4% if they had positive leucocyte esterase test results, 8.3% where the nitrite test was positive and 10.6% when both tests were positive. After multivariate analysis, a positive nitrite test remained an independent risk factor for IBI (odds ratio 2.7, 95% confidence interval 1.4-4.9). CONCLUSION: In infants under 90 days of age with FWS, a positive nitrite urine dipstick test was an independent risk factor for IBI.

Definite bacterial infection in recently vaccinated febrile infants.

AIM: There is insufficient evidence regarding the best approach to evaluating recently vaccinated (RV) infants presenting to the paediatric emergency department with fever. The aim of the present study is to determine the prevalence of bacterial infections in infants presenting with fever within 72 h after vaccination. METHODS: We retrospectively reviewed the electronic medical record of infants aged between 6 and 12 weeks who presented with a fever ≥38°C to the emergency department from January 2016 to December 2018. Febrile infants who were vaccinated within 72 h prior to their emergency department presentation were matched to those who had not received their vaccines in the previous 72 h. Definite serious bacterial infection was diagnosed based on culture results. RESULTS: A total of 198 infants (age: 9 ± 1.84 weeks, male: 119 (60.1%)) were enrolled in this study. Overall, 60 of 138 (30.3%) had received their vaccines within the previous 72 h. The prevalence of bacterial infection in RV infants was 5% compared to 15.2% in non-RV infants (P = 0.056). Interestingly, all vaccinated infants who had proven bacterial infection presented to the emergency department with fever within 24 h of vaccination, and all bacterial infections in that group were urinary tract infections. CONCLUSIONS: The prevalence of bacterial infection among non-RV febrile infants is relatively higher than those RV. However, fever should not be attributed only to the vaccinations, and all febrile RV infants should be carefully evaluated, and at least urine testing should be performed regardless of the time of vaccination.

Reporting and Categorization of Blood Culture Contaminants in Infants and Young Children: A Scoping Review.

BACKGROUND: Blood cultures are obtained routinely for infants and young children for the evaluation for serious bacterial infection. Isolation of organisms that represent possible contaminants poses a management challenge. The prevalence of bacteremia reported in this population is potentially biased by inconsistent contaminant categorization reported in the literature. Our aim was to systematically review the definition and reporting of contaminants within the literature regarding infant bacteremia. METHODS: A search of studies published between 1986 and mid-September 2016 was conducted using Medline/PubMed. Included studies examined children aged 0 to 36 months for whom blood culture was performed as part of a serious bacterial infection evaluation. Studies that involved children in an intensive care unit, prematurely born children, and immunocompromised children or those with an indwelling catheter/device were excluded. Data extracted included contaminant designation methodology, organisms classified as contaminants and pathogens, and contamination and bacteremia rates. DISCUSSION: Our search yielded 1335 articles, and 69 of them met our inclusion criteria. The methodology used to define contaminants was described in 37 (54%) study reports, and 16 (23%) reported contamination rates, which ranged from 0.5% to 22.8%. Studies defined contaminants according to organism species (n = 22), according to the patient's clinical management (n = 4), and using multifactorial approaches (n = 11). Many common organisms, particularly Gram-positive cocci, were inconsistently categorized as pathogens or contaminants. CONCLUSIONS: Reporting and categorization of blood culture contamination are inconsistent within the pediatric bacteremia literature, which limits our ability to estimate the prevalence of bacteremia. Although contaminants are characterized most frequently according to organism, we found inconsistency regarding the classification of certain common organisms. A standardized approach to contaminant reporting is needed.

Risk of Meningitis in Infants Aged 29 to 90 Days with Urinary Tract Infection: A Systematic Review and Meta-Analysis.

OBJECTIVE: To determine the risk of bacterial meningitis in infants aged 29-90 days with evidence of urinary tract infection (UTI). METHODS: PubMed (MEDLINE), Embase, and the Cochrane Library were systematically searched for studies reporting rates of meningitis in infants aged 29-90 days with abnormal urinalysis or urine culture. Observational studies in infants with evidence of UTI who underwent lumbar puncture (LP) reporting age-specific event rates of bacterial meningitis and sterile cerebrospinal fluid pleocytosis were included. Prevalence estimates for bacterial meningitis in infants with UTI were pooled in a random effects meta-analysis. RESULTS: Three prospective and 17 retrospective cohort studies were included in the meta-analysis. The pooled prevalence of concomitant bacterial meningitis in infants with UTI was 0.25% (95% CI, 0.09%-0.70%). Rates of sterile pleocytosis ranged from 0% to 29%. Variation in study methods precluded calculation of a pooled estimate for sterile pleocytosis. In most studies, the decision to perform a LP was up to the provider, introducing selection bias into the prevalence estimate. CONCLUSIONS: The risk of bacterial meningitis in infants aged 29-90 days with evidence of UTI is low. A selective approach to LP in infants identified as low risk for meningitis by other clinical criteria may be indicated.

Impact of Mobile Device-Based Clinical Decision Support Tool on Guideline Adherence and Mental Workload.

OBJECTIVE: To evaluate the individual-level impact of an electronic clinical decision support (ECDS) tool, PedsGuide, on febrile infant clinical decision making and cognitive load. METHODS: A counterbalanced, prospective, crossover simulation study was performed among attending and trainee physicians. Participants performed simulated febrile infant cases with use of PedsGuide and with standard reference text. Cognitive load was assessed using the NASA-Task Load Index (NASA-TLX), which determines mental, physical, temporal demand, effort, frustration, and performance. Usability was assessed with the System Usability Scale (SUS). Scores on cases and NASA-TLX scores were compared between condition states. RESULTS: A total of 32 participants completed the study. Scores on febrile infant cases using PedsGuide were greater compared with standard reference text (89% vs 72%, P = .001). NASA-TLX scores were lower (ie, more optimal) with use of PedsGuide versus control (mental 6.34 vs 11.8, P < .001; physical 2.6 vs 6.1, P = .001; temporal demand 4.6 vs 8.0, P = .003; performance 4.5 vs 8.3, P < .001; effort 5.8 vs 10.7, P < .001; frustration 3.9 vs 10, P < .001). The SUS had an overall score of 88 of 100 with rating of acceptable on the acceptability scale. CONCLUSIONS: Use of PedsGuide led to increased adherence to guidelines and decreased cognitive load in febrile infant management when compared with the use of a standard reference tool. This study employs a rarely used method of assessing ECDS tools using a multifaceted approach (medical decision-making, assessing usability, and cognitive workload,) that may be used to assess other ECDS tools in the future.