Serious bacterial infections in febrile infants in the post-pneumococcal conjugate vaccine era

Serious bacterial infection risk in recently immunized febrile infants in the emergency department

STUDY OBJECTIVES

Fever following immunizations is a common presenting chiefcomplaint among infants. The 2021 American Academy of Pediatrics (AAP) febrile infant clinical practice guidelines exclude recently immunized (RI) infants. This is a challenge for clinicians in the management of the febrile RI young infant. The objective of this study was to assess the prevalence of SBI in RI febrile young infants between 6 and 12 weeks of age.

METHODS

This was a retrospective chart review of infants 6-12 weeks who presented with a fever ≥38 °C to two U.S. military academic Emergency Departments over a four-year period. Infants were considered recently immunized (RI) if they had received immunizations in the preceding 72 h prior to evaluation and not recently immunized (NRI) if they had not received immunizations during this time period. The primary outcome was prevalence of serious bacterial infection (SBI) further delineated into invasive-bacterial infection (IBI) and non-invasive bacterial infection (non-IBI) based on culture and/or radiograph reports.

RESULTS

Of the 508 febrile infants identified, 114 had received recent immunizations in the preceding 72 h. The overall prevalence of SBI was 11.4% (95% CI = 8.9-14.6) in our study population. The prevalence of SBI in NRI infants was 13.7% (95% CI = 10.6-17.6) compared to 3.5% (95% CI = 1.1-9.3) in RI infants. The relative risk of SBI in the setting of recent immunizations was 0.3 (95% CI = 0.1-0.7). There were no cases of invasive-bacterial infections (IBI) in the RI group with all but one of the SBI being urinary tract infections (UTI). The single non-UTI was a case of pneumonia in an infant who presented with respiratory symptoms within 24 h of immunizations.

CONCLUSION

The risk of IBI (meningitis or bacteremia) in RI infants aged 6 to 12 weeks is low. Non-IBI within the first 24 h following immunization was significantly lower than in febrile NRI infants. UTIs remain a risk in the RI population and investigation with urinalysis and urine culture should be encouraged. Shared decision making with families guide a less invasive approach to the care of these children. Future research utilizing a large prospective multi-center data registry would aid in further defining the risk of both IBI and non-IBI among RI infants.

Incidence of Bacteremia and Serious Bacterial Infections in Hyperpyrexic Infants Offered Universal Pneumococcal Conjugate Vaccine 13 and Haemophilus influenzae B Immunization

BACKGROUND

High fevers, especially in young children, often alarm clinicians and prompt extensive evaluation based on perceptions of increased risk of serious bacterial infection (SBI), and even brain damage or seizure disorders.

OBJECTIVE

The aim of this study was to determine the prevalence of SBI in infants aged 3-36 months with fever ≥40.5°C in a population of infants offered universal pneumococcal conjugate vaccine 13 and Haemophilus influenzae B immunization.

METHODS

This study is a retrospective review of all infants aged 3-36 months with temperature ≥40.5°C presenting to a tertiary care pediatric emergency department over a 30-month period in an era of universal pneumococcal conjugate 13 and H. influenzae B immunization.

RESULTS

SBI was recorded in 54 (21.8%) of 247 study infants, most commonly pneumonia 30 patients (12.1%) and urinary tract infection 16 patients (6.5%). Two patients had positive blood cultures, yielding a bacteremia rate of 0.8%. Patients with SBI had a significantly higher WBC count (P < 0.0001) and C-reactive protein levels (P < 0.0001), and were significantly more likely to be hospitalized (P < 0.0001).

DISCUSSION

Although SBI was common (21.8%) in our cohort of hyperpyrexic infants universally offered vaccination with pneumococcal conjugate 13 and H. influenzae B vaccines, bacteremia was a rare finding (0.8%).

Monitoring the efficacy of antibiotic therapy in febrile pediatric oncology patients with bacteremia using infrared spectroscopy of white blood cells-based machine learning

Bacteremia refers to the presence of bacteria in the bloodstream, which can lead to a serious and potentially life-threatening condition. In oncology patients, individuals undergoing cancer treatment have a higher risk of developing bacteremia due to a weakened immune system resulting from the disease itself or the treatments they receive. Prompt and accurate detection of bacterial infections and monitoring the effectiveness of antibiotic therapy are essential for enhancing patient outcomes and preventing the development and dissemination of multidrug-resistant bacteria. Traditional methods of infection monitoring, such as blood cultures and clinical observations, are time-consuming, labor-intensive, and often subject to limitations. This manuscript presents an innovative application of infrared spectroscopy of leucocytes of pediatric oncology patients with bacteremia combined with machine learning to diagnose the etiology of infection as bacterial and simultaneously monitor the efficacy of the antibiotic therapy in febrile pediatric oncology patients with bacteremia infections. Through the implementation of effective monitoring, it becomes possible to promptly identify any indications of treatment failure. This, in turn, indirectly serves to limit the progression of antibiotic resistance. The logistic regression (LR) classifier was able to differentiate the samples as bacterial or control within an hour, after receiving the blood samples with a success rate of over 95 %. Additionally, initial findings indicate that employing infrared spectroscopy of white blood cells (WBCs) along with machine learning is viable for monitoring the success of antibiotic therapy. Our follow up results demonstrate an accuracy of 87.5 % in assessing the effectiveness of the antibiotic treatment.

Pediatric Discharge From the Emergency Department Against Medical Advice

In this Ethics Rounds we present a conflict regarding discharge planning for a febrile infant in the emergency department. The physician believes discharge would be unsafe and would constitute a discharge against medical advice. The child's mother believes her son has been through an already extensive and painful evaluation and would prefer to monitor her well-appearing son closely at home with a safety plan and a next-day outpatient visit. Commentators assess this case from the perspective of best interest, harm-benefit, conflict management, and nondiscriminatory care principles and prioritize a high-quality informed consent process. They characterize the formalization of discharge against medical advice as problematic. Pediatricians, a pediatric resident, ethicists, an attorney, and mediator provide a range of perspectives to inform ethically justifiable options and conflict resolution practices.

A retrospective review of serious infections in febrile infants 0–90 days old

Background:

Fever without source in infants is a common clinical problem that accounts for many ambulatory care visits and hospitalisations. Currently, there is no reliable method of identifying those at risk of serious infection (SI).

Objective:

The goal of this study was to determine the incidence and identify the predictors of SI in febrile infants who presented to the emergency department (ED).

Methods:

This was a single-centre retrospective cohort study of children presenting to a Singapore tertiary hospital paediatric unit between 1 July 2018 and 31 December 2018. Children were included if they were aged 0–90 days and presented to the ED with a fever. SI was defined as urinary tract infection (UTI), sepsis, bacteraemia, meningitis (viral and bacterial), enterocolitis, osteomyelitis, abscess or pneumonia.

Results:

Of the 659 infants, 161 (24.4%) were diagnosed with SI. Meningitis (49.7%) was the most common SI, followed by UTI (45.3%), enterocolitis (5.6%), sepsis (3.1%) and bacteraemia (2.5%). Factors significantly associated with SI were aged 29–60 days, male sex, Severity Index Score (SIS) <10, absolute neutrophil counts >10×109/L, C-reactive protein (CRP) >20 mg/L and procalcitonin >0.5 ng/mL. Multivariate analysis entering all these items retained only male sex, SIS <10 and CRP >20.

Conclusion:

Among hospitalised infants aged 0–90 days, the incidence of SI was 24.4%, and invasive bacterial infection was 0.6%. Meningitis was the most common SI followed by UTI. SIS and CRP can be used to predict SI in infants <90 days old.

Radiographic Pneumonia in Febrile Infants 60 Days and Younger

OBJECTIVE

Few prospective studies have assessed the occurrence of radiographic pneumonia in young febrile infants. We analyzed factors associated with radiographic pneumonias in febrile infants 60 days or younger evaluated in pediatric emergency departments.

STUDY DESIGN

We conducted a planned secondary analysis of a prospective cohort study within 26 emergency departments in a pediatric research network from 2008 to 2013. Febrile (≥38°C) infants 60 days or younger who received chest radiographs were included. Chest radiograph reports were categorized as "no," "possible," or "definite" pneumonia. We compared demographics, Yale Observation Scale scores (>10 implying ill appearance), laboratory markers, blood cultures, and viral testing among groups.

RESULTS

Of 4778 infants, 1724 (36.1%) had chest radiographs performed; 2.7% (n = 46) had definite pneumonias, and 3.9% (n = 67) had possible pneumonias. Patients with definite (13/46 [28.3%]) or possible (15/67 [22.7%]) pneumonias more frequently had Yale Observation Scale score >10 compared with those without pneumonias (210/1611 [13.2%], P = 0.002) in univariable and multivariable analyses. Median white blood cell count (WBC), absolute neutrophil count (ANC), and procalcitonin (PCT) were higher in the definite (WBC, 11.5 [interquartile range, 9.8-15.5]; ANC, 5.0 [3.2-7.6]; PCT, 0.4 [0.2-2.1]) versus no pneumonia (WBC, 10.0 [7.6-13.3]; ANC, 3.4 [2.1-5.4]; PCT, 0.2 [0.2-0.3]; WBC, P = 0.006; ANC, P = 0.002; PCT, P = 0.046) groups, but of unclear clinical significance. There were no cases of bacteremia in the definite pneumonia group. Viral infections were more frequent in groups with definite (25/38 [65.8%]) and possible (28/55 [50.9%]) pneumonias than no pneumonias (534/1185 [45.1%], P = 0.02).

CONCLUSIONS

Radiographic pneumonias were uncommon, often had viruses detected, and were associated with ill appearance, but few other predictors, in febrile infants 60 days or younger.

Direct and indirect effect of 10 valent pneumococcal vaccine on nasopharyngeal carriage in children under 2 years of age in Matiari, Pakistan

Background

Pakistan introduced Ten-valent pneumococcal-conjugate-vaccine PCV10 in 2012 as a 3 + 0 schedule without catch-up.

Methods

Children <2 years old in Matiari, Sindh provided nasopharyngeal swabs between 2014 and 2018, which were cultured for pneumococcus and serotyped through multiplex PCR at the Aga Khan University Hospital. Carriage rates over time for Vaccine-Type (VT) and Non-VT (NVT) serotypes were used to estimate direct, indirect, total and overall effects of vaccination. Regression analysis was used to determine factors associated with VT carriage.

Results

Pneumococcus was detected in 2370/3140 (75%). VT carriage decreased overall, 16.1–9.6% (p-trend <0.001); vaccinated (all 3 doses of PCV10 received) 11.3–8.1% (p-trend 0.031) and unvaccinated (no PCV10 dose received) 17.4–10.3% (p-trend 0.003) with a decline in serotypes 6B, 9V/9A and 19F. Immunization increased from 41.0% to 68.4% (p-trend 0.001). Direct effect of vaccine was 32.8% (95% CI 14.7–47.0%) and indirect effect 44.6%(95% CI 40.6–48.6%). Factors associated with decreased VT colonization were education 1–5 years (aOR 0.7, 95%CI 0.6–1.0), history of difficulty breathing (aOR 0.7, 95%CI 0.5–1.0), exposure to smoke (aOR 0.8, 95% CI 0.6–1.0), child fully immunized (aOR 0.7, 95%CI 0.5–1.0) and enrolled in 3rd (aOR 0.6, 95%CI 0.4–0.8) and 4th (aOR 0.6, 95%CI 0.5–0.9) year of the study whereas history of runny nose (aOR 1.5, 95% CI 1.2–1.9) was positively associated.

Conclusions

Decrease in VT pneumococcal carriage in vaccinated and unvaccinated children indicates herd immunity. Sustained increase in vaccine coverage and close long-term surveillance is warranted.

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.

Diagnosis of inaccessible infections using infrared microscopy of white blood cells and machine learning algorithms

Physicians diagnose subjectively the etiology of inaccessible infections where sampling is not feasible (such as, pneumonia, sinusitis, cholecystitis, peritonitis), as bacterial or viral. The diagnosis is based on their experience with some medical markers like blood counts and medical symptoms since it is harder to obtain swabs and reliable laboratory results for most cases. In this study, infrared spectroscopy with machine learning algorithms was used for the rapid and objective diagnosis of the etiology of inaccessible infections and enables an assessment of the error for the subjective diagnosis of the etiology of these infections by physicians. Our approach allows for diagnoses of the etiology of both accessible and inaccessible infections as based on an analysis of the innate immune system response through infrared spectroscopy measurements of white blood cell (WBC) samples. In the present study, we examined 343 individuals involving 113 controls, 89 inaccessible bacterial infections, 54 accessible bacterial infections, 60 inaccessible viral infections, and 27 accessible viral infections. Using our approach, the results show that it is possible to differentiate between controls and infections (combined bacterial and viral) with 95% accuracy, and enabling the diagnosis of the etiology of accessible infections as bacterial or viral with >94% sensitivity and > 90% specificity within one hour after the collection of the blood sample with error rate <6%. Based on our approach, the error rate of the physicians' subjective diagnosis of the etiology of inaccessible infections was found to be >23%.

Risk factors for urinary tract infections in children aged 0-36months presenting with fever without source and evaluated for risk of serious bacterial infections

BACKGROUND

Children younger than 36 months with fever without a source (FWS) are at risk of serious bacterial infections (SBI). The risk of occult bacteremia (OB) has been greatly reduced in vaccinated children. The aim of this study is to describe the epidemiology of SBI in children with FWS in our setting and to evaluate the performance of our management algorithm.

METHODS

We designed a prospective cohort study. We included children aged 0-36 months presenting with FWS in our emergency unit. Demographic and clinical characteristics, investigations, and management procedures were recorded at the time of inclusion. Information on clinical evolution, final diagnosis, and immunization history were obtained after 10 days. Potential predictors of SBI were compared between patients with and without SBI.

RESULTS

Between October 2015 and September 2017, 173 children were recruited, with a median age of 4.4 months (2.1-1). Of these children, 166 (96%) were up to date with their vaccinations. A total of 47 children (27%) had a final diagnosis of SBI, which were all urinary tract infections (UTI). Presence of chills (odds ratio [OR] 5.6, 95% confidence interval [CI] 1.3-24.3), fever for>2 days (OR 29.1, 95% CI 3.5-243.5), and age<9 months (OR: 45.3, 95% CI: 4.9-415.7) were statistically significant predictors of UTI in a multivariate logistic regression. The sensitivity and specificity of our management algorithm were 100% (95% CI: 92.4-100%) and 21.4% (14.6-29.6%), respectively.

CONCLUSIONS

In the setting of high vaccination coverage, we only identified SBI related to UTIs. We could not identify any OB. Our management algorithm was able to identify all SBI, but specificity was low. Refined criteria for screening of UTI could slightly increase this.

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.

Incidence, clinical profile, and risk factors for serious bacterial infections in children hospitalized with fever in Ujjain, India

Background

Fever is a cause for concern for both parents and the treating pediatrician and a common reason for antibiotic overuse. However, the proportion of children hospitalized for fever with serious bacterial infection (SBI) is uncertain. We aimed to evaluate the epidemiological, clinical, hematological, and biochemical risks for SBI among the children admitted with fever.

Method

This prospective study was conducted in a rural teaching hospital in India on consecutive children, aged 3 months–12 years, presenting with fever 100 °F (37.7 °C) or higher. The presence of SBI was confirmed with one of the following criteria: (a) a positive blood culture; (b) roentgenographically confirmed pneumonia with high titres of C-reactive protein; (c) a culture-confirmed urinary tract infection; (d) enteric fever diagnosed clinically in addition to either a positive blood culture or high Widal titers; and (e) meningitis diagnosed clinically in addition to either a positive blood culture or cerebrospinal fluid culture. A predefined questionnaire was filled.

Results

A total of 302 children were included in the study, out of which 47% (95% CI 41.4–52.7%) presented with SBI. The factors associated with confirmed SBI in bivariate analysis were history of previous hospitalization, history of chronic illness, history of medication in the previous 1 week, a partially immunized child, history of common cold, moderate-grade fever, toxic look, significant lymphadenopathy, absence of BCG scar, delayed development, irritability, breathlessness, respiratory distress, poor feeding, significant weight loss, suspected urinary tract infection, hyponatremia, hypokalemia, and abnormal leucocyte count. The final generalized logistic regression model revealed partially immunized child (RR 4.26), breathlessness (RR 1.80), weight loss (RR 2.28), and suspected urinary tract infection (RR 1.95) as risk factors for the increased risk of SBI.

Conclusion

The study identified multiple risk factors for SBI. Pediatricians can be made aware of these risk factors. Further studies are warranted to identify age-specific risk factors for SBI because most clinicians depend on clinical signs and symptoms to identify SBI.

Rapid diagnosis of infection etiology in febrile pediatric oncology patients using infrared spectroscopy of leukocytes

Rapid diagnosis of the etiology of infection is highly important for an effective treatment of the infected patients. Bacterial and viral infections are serious diseases that can cause death in many cases. The human immune system deals with many viral and bacterial infections that cause no symptoms and pass quietly without treatment. However, oncology patients undergoing chemotherapy have a very weak immune system caused by leukopenia, and even minor pathogen infection threatens their lives. For this reason, physicians tend to prescribe immediately several types of antibiotics for febrile pediatric oncology patients (FPOPs). Uncontrolled use of antibiotics is one of the major contributors to the development of resistant bacteria. Therefore, for oncology patients, a rapid and objective diagnosis of the etiology of the infection is extremely critical. Current identification methods are time-consuming (>24 h). In this study, the potential of midinfrared spectroscopy in tandem with machine learning algorithms is evaluated for rapid and objective diagnosis of the etiology of infections in FPOPs using simple peripheral blood samples. Our results show that infrared spectroscopy enables the diagnosis of the etiology of infection as bacterial or viral within 70 minutes after the collection of the blood sample with 93% sensitivity and 88% specificity.

Differential Diagnosis of the Etiologies of Bacterial and Viral Infections Using Infrared Microscopy of Peripheral Human Blood Samples and Multivariate Analysis

Human viral and bacterial infections are responsible for a variety of diseases that are still the main causes of death and economic burden for society across the globe. Despite the different responses of the immune system to these infections, some of them have similar symptoms, such as fever, sneezing, inflammation, vomiting, diarrhea, and fatigue. Thus, physicians usually encounter difficulties in distinguishing between viral and bacterial infections on the basis of these symptoms. Rapid identification of the etiology of infection is highly important for effective treatment and can save lives in some cases. The current methods used for the identification of the nature of the infection are mainly based on growing the infective agent in culture, which is a time-consuming (over 24 h) and usually expensive process. The main objective of this study was to evaluate the potential of the mid-infrared spectroscopic method for rapid and reliable identification of bacterial and viral infections based on simple peripheral blood samples. For this purpose, white blood cells (WBCs) and plasma were isolated from the peripheral blood samples of patients with confirmed viral or bacterial infections. The obtained spectra were analyzed by multivariate analysis: principle component analysis (PCA) followed by linear discriminant analysis (LDA), to identify the infectious agent type as bacterial or viral in a time span of about 1 h after the collection of the blood sample. Our preliminary results showed that it is possible to determine the infectious agent with high success rates of 82% for sensitivity and 80% for specificity, based on the WBC data.

Occult bacteremia etiology following the introduction of 13-valent pneumococcal conjugate vaccine: a multicenter study in Spain

Little is known about occult bacteremia (OB) in Spain following the introduction of the 13-valent pneumococcal conjugated vaccine (PCV13). Our aim was to describe the microbiologic characteristics and management of OB among children aged 3-36 months in Spain in the era of PCV13. Data were obtained from a multicenter registry of positive blood cultures collected at 22 Spanish emergency departments (ED). Positive blood cultures performed on patients aged 3-36 months from 2011 to 2015 were retrospectively identified. Immunocompetent infants with a final diagnosis of OB were included. Non-well-appearing patients and patients with fever > 72 h were excluded. We analyzed 67 cases (median age 12.5 months [IQR 8.7-19.4]). Thirty-seven (54.4%) had received ≥ 1 dose of PCV. Overall, 47 (70.1%) were initially managed as outpatients (38.3% of them with antibiotic treatment). Phone contact was established with 43 (91.5%) of them after receiving the blood culture result and 11 (23.4%) were hospitalized with parenteral antibiotic. All patients did well. Streptococcus pneumoniae was isolated in 79.1% of the patients (42.2% of the isolated serotypes were included in the PCV13). S. pneumoniae remains the first cause of OB in patients attended in the ED, mainly with non-PCV13 serotypes. Most of the patients with OB were initially managed as outpatients with no adverse outcome.

Central Line-Associated Bloodstream Infection among Children with Intestinal Failure Presenting to the Emergency Department with Fever

OBJECTIVES

To determine which factors confer the greatest risk of central line-associated bloodstream infection (CLABSI) in children with intestinal failure and fever presenting to an emergency department (ED), and to assess whether a low-risk group exists that may not require the standard treatment of admission for 48 hours on intravenous antibiotics pending culture results.

STUDY DESIGN

This retrospective cohort study included children with intestinal failure and fever presenting to an ED over a 6-year period. Multivariable models were created using risk factors selected a priori to be associated with CLABSI as well as univariate predictors with P < .2.

RESULTS

Among 81 patients with 278 ED encounters, 132 (47.5%) CLABSI episodes were identified. Multivariable models showed higher initial temperature in the ED (aOR, 1.99; 95% CI, 1.25-3.17) and low white blood cell count (aOR, 2.65; 95% CI, 1.03-6.79) and platelet count (aOR, 2.65; 95% CI, 1.20-5.87) relative to age-specific reference ranges were strongly associated with CLABSI. Among the 63 encounters in which the patient had none of these risk factors, the rate of CLABSI was 25.4%.

CONCLUSIONS

Children with intestinal failure who present to the ED with fever have high rates of CLABSI. Although higher temperature in the ED, lower white blood cell count, and lower platelet count are strongly associated with CLABSI, patients without these risk factors frequently have positive blood cultures as well. Antibiotics should, therefore, be given to all children with intestinal failure and fever until CLABSI is ruled out.

Post-immunization leucocytosis and its implications for the management of febrile infants

Aims

Clinical guidelines for management of infants with fever but no evident focus of infection recommend that those aged 1–3 months with a white cell count >15 × 10⁹/l have a full septic screen and be admitted for parenteral antibiotics. However, there is limited information about leucocyte changes following routine immunization, a common cause of fever. We investigated white cell counts shortly after routine immunization in Ugandan infants under 3 months of age.

Methods

White cell counts were measured in 212 healthy infants following routine immunizations (DTwP-HepB-Hib, oral polio and pneumococcal conjugate 7 vaccines) received prior to 3 months of age.

Results

Mean leucocyte counts increased from 9.03 × 10⁹/l (95% confidence interval 8.59–9.47 × 10⁹/l) pre-immunizations to 16.46 × 10⁹/l (15.4–17.52 × 10⁹/l) at one-day post-immunizations at 6 weeks of age, and 15.21 × 10⁹/l (14.07–16.36 × 10⁹/l) at one-day post-immunizations at 10 weeks of age. The leucocytosis was primarily a neutrophilia, with neutrophil percentages one-day post-immunization of 49% at 6 weeks of age and 46% at 10 weeks of age. White cell parameters returned to baseline by two-days post-immunization. No participant received antibiotics when presenting with isolated fever post-immunization and all remained well at follow-up.

Conclusions

In our study almost half the children <3 months old presenting with fever but no evident focus of infection at one-day post-immunization met commonly used criteria for full septic screen and admission for parenteral antibiotics, despite having no serious bacterial infection. These findings add to the growing body of literature that questions the utility of white blood cell measurement in identification of young infants at risk of serious bacterial infections, particularly in the context of recent immunizations, and suggest that further exploration of the effect of different immunization regimes on white cell counts is needed.

This observational work was nested within a clinical trial, registration number ISRCTN59683017.

Hyperpyrexia and high fever as a predictor for serious bacterial infection (SBI) in children-a systematic review

It is not clear if children with high fever are at increased risk for serious bacterial infection (SBI). Our aim was to systematically review if children suffering from high fever are at high risk for SBI. Our data sources were Embase, Medline, and Pubmed; from their inception until the last week of March 2017. The study selection were of cohort and case control studies comparing the incidence of SBI in children with hyperpyrexia with children with fever of 41 °C or less, and children with a temperature higher than 40 °C, with children with fever of 40 °C or less. Two reviewers independently pooled studies for detailed review using a structured data-collection form. We calculated the odds ratio and 95% confidence intervals (CI) for SBI, assuming a random-effects model. A sub-group analysis was conducted. In our results, 11 studies met the inclusion criteria. Two studies showed that children with hyperpyrexia are at higher risk for SBI (OR 1.96 95% CI 1.3-1.97). An increased risk for SBI in children with high fever (OR 3.21 95% CI 1.67; 6.22). SBI in infants with temperature over 40 °C was higher compared to infants with lower degree of fever (OR 6.3 95% CI 4.44; 8.95). On older children, the risk for SBI was only slightly higher in children with fever above 40 °C. The limitation of the study is the small amount of studies and that the heterogeneity of the studies was very high.

CONCLUSION

Young infants with temperature higher than 400 °C are at increased risk for SBI. Risk of SBI in older children with temperature > 400C is minimal. What is known: • An association between high fever and increased risk for SBI was reported in young infants. • Based on only two studies from the 1970s and 1980s, hyperpyrexia is associated with increased risk for SBI. What is new: • Infants under the age of 3 months with fever > 40 °C were found to have increased risk for SBI. • Risk of SBI in older children with temperature > 40 °C is minimal.

Incidence and Outcomes of Infections Caused by Multidrug-Resistant Enterobacteriaceae in Children, 2007-2015

BACKGROUND

The escalating incidence of invasive disease caused by multidrug-resistant Gram-negative enteric Enterobacteriaceae (MDR-GNE) is a global concern. Scant published studies in which the epidemiology of these infections in children is described exist; previous studies focused mainly on adults, described circumscribed populations, or lacked clinical detail. The objective of this study was to examine and describe the incidence, risk factors, and outcomes associated with MDR-GNE infection in children.

METHODS

In this cohort study, we used data from 48 children's hospitals maintained by the Pediatric Health Information System. We documented the proportion of MDR-GNE diagnoses among children's hospital patients aged 0 to <18 years who were diagnosed with an Enterobacteriaceae-associated infection between January 1, 2007, and March 31, 2015, and we analyzed the association between MDR-GNE infection and hospital length of stay and death before discharge.

RESULTS

During the study period, 107610 discharges included a diagnosis code for Enterobacteriaceae infection, 724 (0.7%) of which included MDR-GNE infection. The incidence of MDR-GNE, and the proportion of infections with Enterobacteriaceae organisms that were MDR-GNE increased over the study period; from 0.2% in 2007 to 1.5% by 2015 (test for trend < .001). Almost one-quarter (23%) of the infections in children hospitalized for MDR-GNE were nosocomial. Increased odds of MDR-GNE infection were associated with older age and comorbid illnesses. Lengths of stay in patients with MDR-GNE infection were increased 20% (95% confidence interval, 9.9%-30.5%; P < .001) over those without MDR-GNE infection; the increased odds for death did not reach statistical significance (1.46 [95% confidence interval, 0.98-2.18]; P = .06). Results were robust to sensitivity analyses.

CONCLUSIONS

The incidence of pediatric MDR-GNE infection increased during 2007-2015. MDR-GNE infection was associated with increased length of stay, and we found a trend toward increased risk of death. Infections with Gram-negative enteric bacilli are becoming increasingly difficult to treat; considering the global burden of these antimicrobial-resistant organisms, interventions to curtail or even reverse this trend are needed urgently.

Prevalence and characteristics of human parechovirus and enterovirus infection in febrile infants

BACKGROUND

Human parechovirus (HPeV) and human non-polio enterovirus (EV) are important causes of fever without source (FWS) in young infants. Their prevalence and clinical characteristics are largely unknown in Asian countries. This study was conducted to elucidate the epidemiology and clinical characteristics of HPeV and EV infection in febrile young infants in Japan.

METHODS

During February 2010-August 2015, we obtained 53 stool, 44 throat swab, and 20 cerebrospinal fluid samples from 56 infants (<3 months) with FWS at a single hospital. To each sample, we applied reverse transcription-polymerase chain reaction for HPeV and EV. We compared the clinical characteristics of HPeV and EV patients.

RESULTS

HPeV was detected in 11 and EV in 17 patients. HPeV was detected during July-September. HPeV patients, compared with EV patients, had lower age (32 vs 47 days; P = n.s.), higher prevalence of exclusive breast-feeding (81.8 vs 29.4%; P = 0.024), and lower prevalence of sick contacts (36.4 vs 88.2%; P = 0.010). More HPeV than EV patients met the systemic inflammatory response syndrome criteria (90.9 vs 52.9%; P = 0.049). In the HPeV group, leukopenia, thrombopenia, and elevated deviation enzyme were observed, although the prevalence of abnormal cerebrospinal fluid was significantly lower than in the EV group. HPeV patients had longer hospital stay (7 vs 5 days; P = 0.025).

CONCLUSION

HPeV and EV are important causal viruses of FWS. Characteristic clinical pictures exist in these virus infections, but further research is needed to accumulate more cases to produce a comprehensive picture of these virus infections.

Management of the Febrile Young Infant: Update for the 21st Century

Infants aged 90 days or younger with fever are frequently evaluated in the pediatric emergency department. Physical examination findings and individual laboratory investigations are not reliable to differentiate benign viral infections from serious bacterial infections in febrile infants. Clinical prediction models were developed more than 25 years ago and have high sensitivity but relatively low specificity to identify bacterial infections in febrile infants. Newer laboratory investigations such as C-reactive protein and procalcitonin have favorable test characteristics compared with traditional laboratory studies such as a white blood cell count. These novel biomarkers have not gained widespread acceptance because of lack of robust prospectively collected data, varying thresholds to define positivity, and differing inclusion criteria across studies. However, C-reactive protein and procalcitonin, when combined with other patient characteristics in the step-by-step approach, have a high sensitivity for detection of serious bacterial infection. The RNA biosignatures are a novel biomarker under investigation for detection of bacterial infection in febrile infants.

Pneumococcal vaccinations effectively prevent blood culture-negative infections that resemble occult pneumococcal bacteraemia or bacteraemic pneumococcal pneumonia at one to 36 months of age

AIM

The occurrence of blood culture-positive pneumococcal bacteraemia and bacteraemic pneumonia decreased after large-scale pneumococcal vaccinations were introduced. The aim of this study was to evaluate the effect of pneumococcal vaccinations on hospitalisations due to blood culture-negative infections with fever and leucocytosis, without any other focus than pneumonic infiltration.

MATERIAL

This was a retrospective hospital chart review covering the prevaccination era of 2008-2009 and postvaccination era of 2012-2013. The number of study subjects with fever and blood leucocytosis of >17.5 × 10E9/L at one to 36 months of age was 202.

RESULTS

The incidence of hospitalisation for infections associated with fever and leucocytosis, when pneumonic infiltration was present on the chest radiograph, was 4.7/10 000/year, with a 95% confidence interval (95% CI) of 2.2-8.8 in children under 36 months in 2012-2013. When pneumonic infiltration was not present, the respective incidence was 14.6/10 000/year (95% CI: 9.6-21.1). The figure from the 2008-2009 prevaccination era was 11.3 (95% CI: 8.1-15.3) when pneumonic infiltration was present and 24.0/10 000/year (95% CI: 19.2-29.7) when pneumonic infiltration was absent.

CONCLUSION

This study provides evidence of the effectiveness of pneumococcal vaccinations in preventing blood culture-negative infections that resembled occult pneumococcal bacteraemia (pneumococcaemia) or bacteraemic pneumococcal pneumonia at one to 36 months of age.

Challenges in the Etiology and Diagnosis of Acute Febrile Illness in Children in Low- and Middle-Income Countries

Acute febrile illness is a common cause of hospital admission, and its associated infectious causes contribute to substantial morbidity and death among children worldwide, especially in low- and middle-income countries. Declining transmission of malaria in many regions, combined with the increasing use of rapid diagnostic tests for malaria, has led to the increasing recognition of leptospirosis, rickettsioses, respiratory viruses, and arboviruses as etiologic agents of fevers. However, clinical discrimination between these etiologies can be difficult. Overtreatment with antimalarial drugs is common, even in the setting of a negative test result, as is overtreatment with empiric antibacterial drugs. Viral etiologies remain underrecognized and poorly investigated. More-sensitive diagnostics have led to additional dilemmas in discriminating whether a positive test result reflects a causative pathogen. Here, we review and summarize the current epidemiology and focus particularly on children and the challenges for future research.

[Blood cultures in the paediatric emergency department. Guidelines and recommendations on their indications, collection, processing and interpretation]

Blood culture (BC) is the gold standard when a bacteraemia is suspected, and is one of the most requested microbiological tests in paediatrics. Some changes have occurred in recent years: the introduction of new vaccines, the increasing number of patients with central vascular catheters, as well as the introduction of continuous monitoring BC systems. These changes have led to the review and update of different factors related to this technique in order to optimise its use. A practice guideline is presented with recommendations on BC, established by the Spanish Society of Paediatric Emergency Care and the Spanish Society for Paediatric Infectious Diseases. After reviewing the available scientific evidence, several recommendations for each of the following aspects are presented: BC indications in the Emergency Department, how to obtain, transport and process cultures, special situations (indications and interpretation of results in immunosuppressed patients and/or central vascular catheter carriers, indications for anaerobic BC), differentiation between bacteraemia and contamination when a BC shows bacterial growth and actions to take with a positive BC in patients with fever of unknown origin.

[Etiology and clinical course of urinary tract infections in infants less than 3 months-old]

BACKGROUND

Infants less than 3 months of age with urinary tract infection are usually hospitalized. Recent studies show that a less aggressive management for those patients aged ≥ 29 days may be feasible.

OBJECTIVES

To determine the complication rate in infants<3 months of age with urinary tract infection, and to identify the causative agents and their antibiotic susceptibility.

METHODS

A retrospective study was conducted on infants<3 months of age with positive urinalysis results, together with a positive urine culture from a catheterized specimen and seen in the Emergency Department from 2007 to 2012. Demographics, clinical and microbiology (microorganism isolated and antibiotic susceptibility) data were collected. The complications rate (bacteremia, bacterial meningitis, renal abscess, surgical intervention, Intensive Care Unit admission, or death) were calculated for the overall sample and for different age groups (<29, 29-60, and 61-90 days).

RESULTS

A total of 460 patients are included; 137 (29.8%)<29, 166 (36.1%) 29-60, and 157 (34.1%) 61-90 days of age. Twenty four (5.4%; 95% CI: 3.6-7.8) had bacteremia; 15 (10.9%; 95% CI: 6.7-17.3) were<29 days; 8 (4.9%; 95% CI: 2.5-9.4) were 29-60 days, and one (0.7%; 95% CI: 0.1-3.7) was 61-90 days of age (P<.001). One neonate (0.8%; 95% CI: 0.1-4.1) had bacterial meningitis, and 2, renal abscess. Escherichia coli was the common pathogen identified (87.2%) in the urine culture, with a susceptibility to amoxicillin-clavulanate, gentamicin, and cefixime of 89.2, 97.0, and 96.0%, respectively.

CONCLUSION

Complications are low in infants<3 months of age with UTI, especially in those ≥ 29 days of age. The identification of patients at very low risk for complications would allow a less aggressive management. Escherichia coli antibiotic susceptibility remains stable, but continuing careful surveillance is essential to optimize empirical antibiotic treatment.

Afebrile very young infants with urinary tract infection and the risk for bacteremia

BACKGROUND

Some authors have assessed the utility of considering various risk factors in predicting bacteremia in young infants with urinary tract infection (UTI) in studies that included only febrile patients. Our aims were to determine whether fever was a predictor for bacteremia and to identify other associated risk factors.

METHODS

A retrospective study was conducted that included infants 29 to 90 days of age with UTI attended in the Pediatric Emergency Department from September 2006 through May 2013. UTI was defined as growth of ≥ 50,000 colony forming units/mL of a single pathogen from a catheterized specimen in association with an abnormal urinalysis. Patients without a blood culture were excluded. Univariate testing was used to identify clinical and laboratory factors associated with bacteremia. Receiver operating characteristic curves were constructed for the laboratory markers associated with bacteremia.

RESULTS

We analyzed 350 patients; 77 (22%) were afebrile. Ten had bacteremia (2.9%, 95% confidence interval: 1.6%-5.2%). No other adverse events were identified. No differences were found in bacteremia rates between febrile and afebrile patients (2.9% vs. 2.6%; P = 1.0). Risk factors detected for bacteremia were classified as not well-appearing (25.0% vs. 2.1%; P = 0.003) and a procalcitonin value ≥ 0.7 ng/mL (6.4% vs. 0.5%; P = 0.001). These low-risk criteria yielded a sensitivity of 88.9% for detecting bacteremia with a negative predictive value of 99.5%.

CONCLUSIONS

Afebrile young infants with UTI should not be classified a priori as low risk for bacteremia. Well-appearing young infants with UTI and procalcitonin value <0.7 ng/mL were at very low risk for bacteremia; outpatient management with an appropriate follow-up could be considered.

Costo-Efectividad de la Proteína C Reactiva, Procalcitonina y Escala de Rochester: Tres Estrategias Diagnosticas para la Identificación de Infección Bacteriana Severa en Lactantes Febriles sin Foco

OBJECTIVE

The optimal practice management of highly febrile 1- to 3-month-old children without a focal source has been controversial. The release of a conjugate pneumococcal vaccine may reduce the rate of occult bacteremia and alter the utility of empiric testing. The objective of this study was to determine the cost-effectiveness of 3 different screening strategies of Serious Bacterial Infections (SBI) in Children Presenting with Fever without Source in Argentina.

METHODS

Cost-effectiveness (CE) analysis was performed to compare the strategies of procalcitonin, C reactive protein and Rochester criteria. A hypothetical cohort of 10 000 children who were 1 to 3 months of age and had a fever of >39°C and no source of infection was modeled for each strategy. Our main outcome measure was incremental CE ratios.

RESULTS

C reactive protein result in US$ 937 per correctly diagnosed cases of SBI. The additional cost per additional correct diagnosis using procalcitonin versus C reactive protein was U$6127 while Rochester criteria resulted dominated.

CONCLUSIONS

C reactive protein is the strategy more cost-effective to detect SBI in children with Fever without Source in Argentina. Due to low proportion of correctly diagnosed cases (< 80%) of three tests in the literature and our study, however; an individualized approach for children with fever is still necessary to optimize diagnostic investigations and treatment in the different emergency care settings.

Comparison of underlying factors behind parental refusal or consent for lumbar puncture

BACKGROUND

Although lumbar puncture (LP) is a safe procedure in experienced hands, some parents fear having it performed on their children and refuse consent. The factors associated with this refusal are unclear, and any differences with consenting parents might provide clues as to how to address them. Therefore, we compared the underlying factors between the parents who refuse and those who consent to this procedure, as well as their children's outcomes.

METHODS

A prospective study of the two groups of parents was conducted by a face-to-face structured interview. Parents' demographic factors, knowledge, perceptions, beliefs and attitudes, as well as their children's outcomes, were compared. The odds ratio (OR) with 95% confidence intervals was calculated for significant associations.

RESULTS

Consent was declined by 24 out of 55 families (44%). Alternative options were offered more often to those refusing consent (OR=5.7). Significantly more parents who refused consent also refused bladder catheterization (OR=18), knowing someone with complications following LP (OR=8.7), felt that it was not needed (OR=7.9) or that it induced complications (OR=12.5). A significantly higher proportion of the consenting parents were aware that meningitis might cause convulsions (OR=4.6), deafness or blindness (OR=2.9).

CONCLUSION

The differences in the understanding, perceptions, beliefs and fears between the parents who refused consent and those who agreed, can provide clues to the developing of appropriate strategies when requesting consent for LP.

Use of urine testing in outpatients treated for urinary tract infection

OBJECTIVE

To characterize urine test use in ambulatory, antibiotic-treated pediatric urinary tract infection (UTI).

METHODS

We studied children <18 years who had an outpatient UTI and a temporally associated antibiotic prescription from 2002 through 2007 by using a large claims database, Innovus i3. We evaluated urine-testing trends and performed multivariable logistic regression to assess for factors associated with urine culture use.

RESULTS

Of 40 603 treated UTI episodes in 28 678 children, urinalysis was performed in 76%, and urine culture in 57%; 32% of children <2 years had no urinalysis or culture performed for an antibiotic-treated UTI episode. Urine culture use decreased during the study period from 60% to 54% (P < .001). We observed variation in urine culture use with age (<2 years: odds ratio [OR] 1.0, 95% confidence interval [CI] 0.9-1.1; 2-5 years: OR 1.3, 95% CI 1.2-1.4; 6-12 years: OR 1.3, 95% CI 1.2-1.4, compared with 13-17 years); gender (boys: OR 0.8, 95% CI 0.8-0.9); and specialty (pediatrics: OR 2.6, 95% CI 2.5-2.8; emergency medicine, OR 1.2, 95% CI 1.1-1.3; urology: OR 0.5, 95% CI 0.4-0.6, compared with family/internal medicine). Recent antibiotic exposure (OR 1.1, 95% CI 1.1-1.2) and empirical broad-spectrum prescription (OR 1.2, 95% CI 1.1-1.2) were associated with urine culture use, whereas previous UTI and urologic anomalies were not.

CONCLUSIONS

Providers often do not obtain urine tests when prescribing antibiotics for outpatient pediatric UTI. Variation in urine culture use was observed based on age, gender, and physician specialty. Additional research is necessary to determine the implications of empirical antibiotic prescription for pediatric UTI without confirmatory urine testing.

Gene expression profiles in febrile children with defined viral and bacterial infection

Viral infections are common causes of fever without an apparent source in young children. Despite absence of bacterial infection, many febrile children are treated with antibiotics. Virus and bacteria interact with different pattern recognition receptors in circulating blood leukocytes, triggering specific host transcriptional programs mediating immune response. Therefore, unique transcriptional signatures may be defined that discriminate viral from bacterial causes of fever without an apparent source. Gene expression microarray analyses were conducted on blood samples from 30 febrile children positive for adenovirus, human herpesvirus 6, or enterovirus infection or with acute bacterial infection and 22 afebrile controls. Blood leukocyte transcriptional profiles clearly distinguished virus-positive febrile children from both virus-negative afebrile controls and afebrile children with the same viruses present in the febrile children. Virus-specific gene expression profiles could be defined. The IFN signaling pathway was uniquely activated in febrile children with viral infection, whereas the integrin signaling pathway was uniquely activated in children with bacterial infection. Transcriptional profiles classified febrile children with viral or bacterial infection with better accuracy than white blood cell count in the blood. Similarly accurate classification was shown with data from an independent study using different microarray platforms. Our results support the paradigm of using host response to define the etiology of childhood infections. This approach could be an important supplement to highly sensitive tests that detect the presence of a possible pathogen but do not address its pathogenic role in the patient being evaluated.

Update on urinary tract infections in the emergency department

PURPOSE OF REVIEW

To review recent changes in the diagnostic and therapeutic approach to pediatric urinary tract infection in the emergency department.

RECENT FINDINGS

Updated guidelines from the American Academy of Pediatrics have significantly changed the approach to UTI, risk-stratifying patients according to their likelihood of UTI, and re-defining criteria for diagnosis of UTI. New studies have delineated important risk factors for concomitant bacteremia and adverse events. Procalcitonin has emerged as the inflammatory marker most predictive of upper versus lower urinary tract infection and renal scarring. Delays in empiric antibiotic therapy are associated with increased rates of renal scarring. Corticosteroids are a potential adjunctive therapy to antibiotics.

SUMMARY

Timely diagnosis and therapy of UTI are essential. New guidelines may alter the traditional approach to evaluation and management. Future studies will likely focus on the impact of the new guidelines, further delineate the role of procalcitonin in predicting UTI, and explore the role of corticosteroids as an adjunct to antibiotic therapy.

Detection of viruses in young children with fever without an apparent source

OBJECTIVE

Fever without an apparent source is common in young children. Currently in the United States, serious bacterial infection is unusual. Our objective was to determine specific viruses that might be responsible.

METHODS

We enrolled children aged 2 to 36 months with temperature of 38°C or greater without an apparent source or with definite or probable bacterial infection being evaluated in the St Louis Children's Hospital Emergency Department and afebrile children having ambulatory surgery. Blood and nasopharyngeal swab samples were tested with an extensive battery of virus-specific polymerase chain reaction assays.

RESULTS

One or more viruses were detected in 76% of 75 children with fever without an apparent source, 40% of 15 children with fever and a definite or probable bacterial infection, and 35% of 116 afebrile children (P < .001). Four viruses (adenovirus, human herpesvirus 6, enterovirus, and parechovirus) were predominant, being detected in 57% of children with fever without a source, 13% of children with fever and definite or probable bacterial infection, and 7% of afebrile children (P < .001). Thirty-four percent of 146 viral infections were detected only by polymerase chain reaction performed on blood. Fifty-one percent of children with viral infections and no evidence of bacterial infection were treated with antibiotics.

CONCLUSIONS

Viral infections are frequent in children with fever without an apparent source. Testing of blood in addition to nasopharyngeal secretions expanded the range of viruses detected. Future studies should explore the utility of testing for the implicated viruses. Better recognition of viruses that cause undifferentiated fever in young children may help limit unnecessary antibiotic use.

Sequence analysis of the human virome in febrile and afebrile children

Unexplained fever (UF) is a common problem in children under 3 years old. Although virus infection is suspected to be the cause of most of these fevers, a comprehensive analysis of viruses in samples from children with fever and healthy controls is important for establishing a relationship between viruses and UF. We used unbiased, deep sequencing to analyze 176 nasopharyngeal swabs (NP) and plasma samples from children with UF and afebrile controls, generating an average of 4.6 million sequences per sample. An analysis pipeline was developed to detect viral sequences, which resulted in the identification of sequences from 25 viral genera. These genera included expected pathogens, such as adenoviruses, enteroviruses, and roseoloviruses, plus viruses with unknown pathogenicity. Viruses that were unexpected in NP and plasma samples, such as the astrovirus MLB-2, were also detected. Sequencing allowed identification of virus subtype for some viruses, including roseoloviruses. Highly sensitive PCR assays detected low levels of viruses that were not detected in approximately 5 million sequences, but greater sequencing depth improved sensitivity. On average NP and plasma samples from febrile children contained 1.5- to 5-fold more viral sequences, respectively, than samples from afebrile children. Samples from febrile children contained a broader range of viral genera and contained multiple viral genera more frequently than samples from children without fever. Differences between febrile and afebrile groups were most striking in the plasma samples, where detection of viral sequence may be associated with a disseminated infection. These data indicate that virus infection is associated with UF. Further studies are important in order to establish the range of viral pathogens associated with fever and to understand of the role of viral infection in fever. Ultimately these studies may improve the medical treatment of children with UF by helping avoid antibiotic therapy for children with viral infections.

Bacteremia in feverish children presenting to the emergency department: a retrospective study and literature review

AIM

To evaluate the incidence of bacteremia, and the isolated pathogens, in well-appearing children with fever without source (FWS) presenting to the pediatric emergency department (PED), after pneumococcal conjucate vaccine - 7 valent (PCV-7) widespread introduction in the Veneto region of north-eastern Italy, and to review the main literature contributions on the subject.

METHODS

Blood cultures performed at the PED of Padova from 1 June 2006 to 31 January 2009 in febrile children aged 1-36 months were retrospectively retrieved. Medical records of previously healthy well-appearing children with FWS were identified and reviewed.

RESULTS

The study finally included 392 patients. Bacteremia rate was 0.34% (95% CI 0-1) in the age group 3-36 months and 2% (95% CI 0-4.7) in infants 1-3 months. No Streptococcus pneumoniae was isolated. The literature review identified 10 relevant studies carried out in the USA and Spain showing an overall bacteremia rate <1% for feverish children aged 3-36 months, with values <0.5% in settings with high PCV-7 coverage.

CONCLUSION

Overall bacteremia rate is currently <0.5% in well-appearing children aged 3-36 months with FWS attending the PED in areas with PCV-7 widespread vaccination and is sufficiently low to preclude laboratory testing in favour of close follow-up. Further research is needed to evaluate a more conservative approach in infants 2-3 months of age.

Evaluation of the precision of emergency department diagnoses in young children with fever

OBJECTIVE. To characterize causes of fever in children presenting to a pediatric emergency department (ED). METHODS. One-year retrospective review of ED records. Inclusion criteria were 2 to 36 months of age with a documented temperature ≥ 39°C. Exclusion criteria were elopement, repeat visit, and underlying diagnosis with a predisposition to infection. Medical records were reviewed using a predefined, study-specific, data abstraction tool. Based on diagnosis and pathogen detection, visits were assigned to 3 groups, laboratory confirmed pathogen and focal or nonfocal diagnosis without confirmed pathogen. RESULTS. A total of 1091 visits met inclusion criteria. Fourteen percent had a pathogen detected, 56% had a focal diagnosis without a confirmed pathogen, and 30% had a nonfocal diagnosis without confirmed pathogen. CONCLUSIONS. In a cohort of febrile children 2 to 36 months of age, only 14% had a confirmed pathogen. New rapid viral diagnostic techniques may provide an opportunity to improve diagnostic certainty in young children presenting with fever.

Should blood cultures be obtained in all infants 3 to 36 months presenting with significant fever?

CONTEXT

Fever without source (FWS) in children 3-36 months is a common presenting complaint. Because of changes in immunization practices and their effects on rates of bacteremia, older guidelines may no longer be applicable. We reviewed the literature regarding the necessity of obtaining a blood culture in non-toxic children in this age group with FWS.

DATA SOURCES

We conducted a MEDLINE search on the topic of bacteremia in febrile children 3-36 months from 2004-present.

RESULTS

Eight studies were included. Although the studies varied in terms of approach and analysis, all suggested a rate of bacteremia in a non-toxic, febrile child 3-36 months of age to be less than 1%.

CONCLUSIONS

Strong consideration should be given for foregoing blood culture in a non-toxic child 3-36 months of age with FWS.