Epidemiology and Antimicrobial Susceptibility of Invasive Bacterial Infections in Children-A Population-Based Study From Norway

Recovery of pathogens with implementation of a weight-based algorithm for pediatric blood cultures: an observational intervention study

BACKGROUND

Recovering pathogenic bacteria and yeast from pediatric blood cultures and reliably distinguishing between pathogens and contaminants are likely to be improved by increasing the volume of blood submitted to microbiology laboratories for culturing beyond the low volumes that have historically have been used. The primary aim of this study was to assess whether the pathogen recovery rate would increase after implementation of a weight-based algorithm for determining the intended volume of blood submitted for culturing. Secondary aims were to: 1) evaluate the effects of the algorithm implementation on the blood culture contamination rate; 2) determine whether pathogens might be found more often than contaminants in several as opposed to single bottles when more than one bottle is submitted; and 3) describe the microbiological findings for pathogens and contaminants in blood cultures by applying a clinical validation of true blood culture positivity.

METHODS

A pre-post comparison of positivity and contamination rates after increasing the theoretical blood volume and number of blood culture bottles was performed, on the basis of a clinical validation of blood culture findings as pathogens vs contaminants.

RESULTS

We examined 5327 blood cultures, including 186 with growth (123 true positives and 63 contaminated). The rate of true positive blood cultures significantly increased from 1.6% (42/2553) pre to 2.9% (81/2774, p = .002) post intervention. The rate of contaminated blood cultures did not change significantly during the study period (1.4% [35/2553] pre vs 1.0% [28/2774], p = .222) post intervention), but the proportion of contaminated cultures among all positive cultures decreased from 45% (35/77) pre to 26% (28/109, p = .005) post intervention. A microorganism that grew in a single bottle was considered a contaminant in 35% (8/23) of cases, whereas a microorganism that grew in at least two bottles was considered a contaminant in 2% (1/49, p < .001) of cases. According to common classification criteria relying primarily on the identity of the microorganism, 14% (17/123) of the recovered pathogens would otherwise have been classified as contaminants.

CONCLUSION

Implementation of a weight-based algorithm to determine the volume and number of blood cultures in pediatric patients is associated with an increase in the pathogen recovery rate.

Bacterial etiology and antimicrobial resistance pattern of pediatric bloodstream infections: a 5-year experience in an Iranian referral hospital

BACKGROUND

Bloodstream infections (BSI) are the major cause of morbidity and mortality in children in developing countries. The purpose of the current study was to establish the antimicrobial susceptibility pattern of bacterial isolates from bloodstream infections at Children's Medical Center Hospital (CMC), Tehran, Iran.

METHODS

We retrospectively recorded all positive blood cultures and antimicrobial susceptibility of all bloodstream isolates among children admitted to CMC, during 5 years. Specimen culture, bacterial identification, and antimicrobial susceptibility testing were performed according to standard laboratory methods.

RESULTS

From 3,179 pathogens isolated from the blood cultures 2,824 bacteria were cultured, with 1,312 cases being identified as Gram-positive bacteria (46%) and 1,512 cases as Gram-negative bacteria (54%). The most common Gram-negative bacteria isolated were as follows: Pseudomonas spp. (n = 266, 17.6%), Klebsiella pneumoniae (n = 242, 16%), Stenotrophomonas maltophilia (n = 204, 13.5%), Enterobacter spp. (n = 164, 10.8%), Escherichia coli (n = 159, 10.5%), Pseudomonas aeruginosa (n = 126, 8.3%), Serratia marcescens (n = 121, 8%), and Acinetobacter baumannii (n = 73, 4.8%). The most common Gram-positive bacteria isolated were coagulase-negative staphylococci (CONS) (n = 697, 53%), Streptococcus spp. (n = 237, 18%), Staphylococcus aureus (n = 202, 15%) and Enterococcus spp. (n = 167, 12.7%). 34% of bacterial strains were isolated from ICUs. The rates of methicillin resistance in S. aureus and CONS were 34% and 91%, respectively. E. coli isolates showed high resistance to cefotaxime (84%). All isolates of K. pneumoniae were susceptible to colistin and 56% were susceptible to imipenem. P. aeruginosa isolates showed high susceptibility to all antibiotics.

CONCLUSIONS

Our findings emphasize the need of clinicians having access to up-to-date bacterial susceptibility data for routinely prescribed drugs. Continuous monitoring of changes in bacterial resistance will aid in the establishment of national priorities for local intervention initiatives in Iran. The increased risk of BSI caused by antibiotic-resistant organisms, emphasizes the significance of implementing appropriate antibiotic prescribing regulations and developing innovative vaccination techniques in Iran.

Antibiotic resistance monitoring in wastewater in the Nordic countries: A systematic review

The Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) have effectively kept lower antibiotic-resistant bacterial (ARB) pathogen rates than many other countries. However, in recent years, these five countries have encountered a rise in ARB cases and challenges in treating infections due to the growing prevalence of ARB pathogens. Wastewater-based surveillance (WBS) is a valuable supplement to clinical methods for ARB surveillance, but there is a lack of comprehensive understanding of WBS application for ARB in the Nordic countries. This review aims to compile the latest state-of-the-art developments in WBS for ARB monitoring in the Nordic countries and compare them with clinical surveillance practices. After reviewing 1480 papers from the primary search, 54 were found relevant, and 15 additional WBS-related papers were included. Among 69 studies analyzed, 42 dedicated clinical epidemiology, while 27 focused on wastewater monitoring. The PRISMA review of the literature revealed that Nordic countries focus on four major WBS objectives of ARB: assessing ARB in the human population, identifying ARB evading wastewater treatment, quantifying removal rates, and evaluating potential ARB evolution during the treatment process. In both clinical and wastewater contexts, the most studied targets were pathogens producing carbapenemase and extended-spectrum beta-lactamase (ESBL), primarily Escherichia coli and Klebsiella spp. However, vancomycin-resistant Enterococcus (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) have received more attention in clinical epidemiology than in wastewater studies, probably due to their lower detection rates in wastewater. Clinical surveillance has mostly used culturing, antibiotic susceptibility testing, and genotyping, but WBS employed PCR-based and metagenomics alongside culture-based techniques. Imported cases resulting from international travel and hospitalization abroad appear to have frequently contributed to the rise in ARB pathogen cases in these countries. The many similarities between the Nordic countries (e.g., knowledge exchange practices, antibiotic usage patterns, and the current ARB landscape) could facilitate collaborative efforts in developing and implementing WBS for ARB in population-level screening.

Clinical Practice Guideline by the Pediatric Infectious Diseases Society (PIDS) and the Infectious Diseases Society of America (IDSA): 2023 Guideline on Diagnosis and Management of Acute Bacterial Arthritis in Pediatrics

This clinical practice guideline for the diagnosis and treatment of acute bacterial arthritis (ABA) in children was developed by a multidisciplinary panel representing the Pediatric Infectious Diseases Society (PIDS) and the Infectious Diseases Society of America (IDSA). This guideline is intended for use by healthcare professionals who care for children with ABA, including specialists in pediatric infectious diseases and orthopedics. The panel's recommendations for the diagnosis and treatment of ABA are based upon evidence derived from topic-specific systematic literature reviews. Summarized below are the recommendations for the diagnosis and treatment of ABA in children. The panel followed a systematic process used in the development of other IDSA and PIDS clinical practice guidelines, which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE approach (Grading of Recommendations Assessment, Development and Evaluation) (see Figure 1). A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Late-onset sepsis in very preterm infants in Norway in 2009-2018: a population-based study

OBJECTIVE

To evaluate epidemiology and outcomes among very preterm infants (<32 weeks' gestation) with culture-positive and culture-negative late-onset sepsis (LOS).

DESIGN

Cohort study using a nationwide, population-based registry.

SETTING

21 neonatal units in Norway.

PARTICIPANTS

All very preterm infants born 1 January 2009-31 December 2018 and admitted to a neonatal unit.

MAIN OUTCOME MEASURES

Incidences, pathogen distribution, LOS-attributable mortality and associated morbidity at discharge.

RESULTS

Among 5296 very preterm infants, we identified 582 culture-positive LOS episodes in 493 infants (incidence 9.3%) and 282 culture-negative LOS episodes in 282 infants (incidence 5.3%). Extremely preterm infants (<28 weeks' gestation) had highest incidences of culture-positive (21.6%) and culture-negative (11.1%) LOS. The major causative pathogens were coagulase-negative staphylococci (49%), Staphylococcus aureus (15%), group B streptococci (10%) and Escherichia coli (8%). We observed increased odds of severe bronchopulmonary dysplasia (BPD) associated with both culture-positive (adjusted OR (aOR) 1.7; 95% CI 1.3 to 2.2) and culture-negative (aOR 1.6; 95% CI 1.3 to 2.6) LOS. Only culture-positive LOS was associated with increased odds of cystic periventricular leukomalacia (cPVL) (aOR 2.2; 95% CI 1.4 to 3.4) and severe retinopathy of prematurity (ROP) (aOR 1.8; 95% CI 1.2 to 2.8). Culture-positive LOS-attributable mortality was 6.3%, higher in Gram-negative (15.8%) compared with Gram-positive (4.1%) LOS, p=0.009. Among extremely preterm infants, survival rates increased from 75.2% in 2009-2013 to 81.0% in 2014-2018, p=0.005. In the same period culture-positive LOS rates increased from 17.1% to 25.6%, p<0.001.

CONCLUSIONS

LOS contributes to a significant burden of disease in very preterm infants and is associated with increased odds of severe BPD, cPVL and severe ROP.

Antibiotic Use in Children Before, During and After Hospitalization

Purpose

To investigate ambulatory antibiotic use in children during 1 year before and 1 year after in‐hospital antibiotic exposure compared to children from the general population that had not received antibiotics in‐hospital.

Methods

Explorative data‐linkage cohort study from Norway of children aged 3 months to 17 years. One group had received antibiotics in‐Hospital (H+), and one group had not received antibiotics in‐hospital (H‐). The H+ group was recruited during admission in 2017. Using the Norwegian Population Registry, 10 children from the H‐ group were matched with one child from the H+ group according to county of residence, age and sex. We used the Norwegian Prescription Database to register antibiotic use 1 year before and 1 year after the month of hospitalisation.

Results

Of 187 children in the H+ group, 83 (44%) received antibiotics before hospitalisation compared to 288/1870 (15%) in the H‐ group, relative risk (RR) 2.88 (95% confidence interval 2.38–3.49). After hospitalisation, 86 (46%) received antibiotics in the H+ group compared to 311 (17%) in the H‐ group, RR 2.77 (2.30–3.33). Comorbidity‐adjusted RR was 2.30 (1.84–2.86) before and 2.25 (1.81–2.79) after hospitalisation. RR after hospitalisation was 2.55 (1.99–3.26) in children 3 months‐2 years, 4.03 (2.84–5.71) in children 3–12 years and 2.07 (1.33–3.20) in children 13–17 years.

Conclusions

Children exposed to antibiotics in‐hospital had two to three times higher risk of receiving antibiotics in ambulatory care both before and after hospitalisation. The link between in‐hospital and ambulatory antibiotic exposure should be emphasised in future antibiotic stewardship programs.

OUP accepted manuscript

Objectives

To investigate whether infants exposed to antimicrobials in hospital during the first 3 months of life had an increased risk of ambulatory antimicrobial use during the following year compared with infants not exposed to antimicrobials during the first 3 months of life.

Methods

Norwegian cohort study of infants less than 3 months consisting of one group exposed to antimicrobials recruited during hospitalization and one group not exposed to antimicrobials. Ten unexposed infants were matched with one exposed infant according to county of residence, birth year and month, and sex. The Norwegian Prescription Database was applied to register antimicrobial use from the month after discharge and 1 year onward. We defined comorbidity based on antimicrobials prescribed as reimbursable prescriptions due to underlying diseases.

Results

Of 95 infants exposed to antimicrobials during the first 3 months of life, 23% had recurrent use compared with 14% use in 950 unexposed infants [relative risk (RR) = 1.7 (95% CI = 1.1–2.5) and comorbidity-adjusted RR = 1.4 (95% CI = 0.9–2.2)]. The recurrence use rate in exposed term infants (≥37 weeks, n = 70) was 27% compared with 12% in their unexposed matches [RR 2.3 = (95% CI = 1.4–3.7) and comorbidity-adjusted RR = 1.9 (95% CI = 1.2–3.2). Of 25 exposed preterm infants, 3 (12%) had recurrent use. The total antimicrobial prescription rate was 674/1000 in the exposed group and 244/1000 in the unexposed group [incidence rate ratio = 2.8 (95% CI = 1.6–4.9)].

Conclusions

Infants exposed to antimicrobials during the first 3 months of life had an increased risk of recurrent use during the following year. This increased risk also appeared in term infants without infection-related comorbidity.

Half of all hospitalised children treated with antibiotics for pneumonia did not fulfil radiological, microbiological or laboratory criteria

AIM

Evaluating the management of paediatric pneumonia is important. We aimed to estimate the proportion of children receiving antibiotics for suspected community-acquired pneumonia (CAP) that were likely to have a bacterial infection. Furthermore, we described antibiotic use in relation to guidelines.

METHODS

We conducted a prospective observational study from a paediatric department in Norway. During 2017, all admitted children aged 0-17 years receiving antibiotics for CAP were enrolled in the study. We collected relevant data and defined likely CAP as one or more of the following: radiologically confirmed pneumonia, c-reactive protein of at least 100 mg/L, positive bacterial culture from blood or pleura, detection of bacteria from the nasopharynx associated with atypical pneumonia.

RESULTS

In total, 70 episodes of suspected CAP were included. Median age was 41.5 months, and 36 (51%) were girls. Of all treatments, 38 (54%) fulfilled our criteria for likely CAP. Median duration of treatment was 10 days. Of empirical treatments, 36 (57%) only involved penicillin. None of the children had neutropenia or complications, and only two needed intensive care.

CONCLUSION

Only half of children receiving antibiotics for suspected CAP were likely to have bacterial infection. Despite no obvious reason, antibiotic treatment was longer than currently recommended.