Chorioamnionitis and Culture-Confirmed, Early-Onset Neonatal Infections

[Advances in clinical management of neonatal sepsis]

Neonatal sepsis, as a significant cause of various complications and adverse outcomes in neonates, remains a serious health burden both domestically and internationally. Strategies such as antibiotic prophylaxis during delivery, the utilization of early-onset sepsis risk calculators, and quality improvement initiatives in neonatal wards are beneficial in alleviating the disease burden of neonatal sepsis. This paper provides a review of the epidemiology, risk factors, and recent advances in clinical management of neonatal sepsis.

Resource Utilization and Costs Associated with Approaches to Identify Infants with Early-Onset Sepsis

Objective. To compare resource utilization and costs associated with 3 alternative screening approaches to identify early-onset sepsis (EOS) in infants born at ≥35 wk of gestational age, as recommended by the American Academy of Pediatrics (AAP) in 2018. Study Design. Decision tree-based cost analysis of the 3 AAP-recommended approaches: 1) categorical risk assessment (categorization by chorioamnionitis exposure status), 2) neonatal sepsis calculator (a multivariate prediction model based on perinatal risk factors), and 3) enhanced clinical observation (assessment based on serial clinical examinations). We evaluated resource utilization and direct costs (2022 US dollars) to the health system. Results. Categorical risk assessment led to the greatest neonatal intensive care unit usage (210 d per 1,000 live births) and antibiotic exposure (6.8%) compared with the neonatal sepsis calculator (112 d per 1,000 live births and 3.6%) and enhanced clinical observation (99 d per 1,000 live births and 3.1%). While the per-live birth hospital costs of the 3 approaches were similar-categorical risk assessment cost $1,360, the neonatal sepsis calculator cost $1,317, and enhanced clinical observation cost $1,310-the cost of infants receiving intervention under categorical risk assessment was approximately twice that of the other 2 strategies. Results were robust to variations in data parameters. Conclusion. The neonatal sepsis calculator and enhanced clinical observation approaches may be preferred to categorical risk assessment as they reduce the number of infants receiving intervention and thus antibiotic exposure and associated costs. All 3 approaches have similar costs over all live births, and prior literature has indicated similar health outcomes. Inclusion of downstream effects of antibiotic exposure in the neonatal period should be evaluated within a cost-effectiveness analysis.

Highlights

Of the 3 approaches recommended by the American Academy of Pediatrics in 2018 to identify early-onset sepsis in infants born at ≥35 weeks, the categorical risk assessment approach leads to about twice as many infants receiving evaluation to rule out early-onset sepsis compared with the neonatal sepsis calculator and enhanced clinical observation approaches.While the hospital costs of the 3 approaches were similar over the entire population of live births, the neonatal sepsis calculator and enhanced clinical observation approaches reduce antibiotic exposure, neonatal intensive care unit admission, and hospital costs associated with interventions as part of the screening approach compared with the categorical risk assessment approach.

Clinical and economic impacts of a modified-observational screening approach to well-appearing infants born to mothers with chorioamnionitis

OBJECTIVE

Term infants born to mothers with chorioamnionitis are at risk for early-onset sepsis (EOS). We aimed to measure the impact of changing from a categorical to a modified-observational EOS screening approach on NICU admission, antibiotic utilization, and hospitalization costs.

STUDY DESIGN

Single-center retrospective pre-post cohort study of full-term infants born to mothers with chorioamnionitis. Primary outcomes included NICU admission, antibiotic utilization, and hospitalization costs. Outcomes were adjusted for demographic variables. Budget-impact analysis was performed using bootstrapping with replication.

RESULTS

380 term infants were included (197 categorical; 183 modified-observational). There was a significant decrease in NICU admission and antibiotic utilization (p < 0.05) in the modified-observational cohort but no significant difference in per-patient total hospitalization costs. Budget-impact analysis suggested a high probability of cost savings.

CONCLUSION

A modified-observational approach to evaluating term infants of mothers with chorioamnionitis can reduce NICU admission and unnecessary antibiotic therapy, and may lead to cost-savings.

Possible Rates of Detection of Neonatal Sepsis Pathogens in the Context of Microbiological Diagnostics in Mothers - Real World Data

Objective

The aim of this study was to identify the rate of detection of neonatal sepsis pathogens in maternal microbiological smears.

Study Design

This is a retrospective study conducted at a Level 1 perinatal center in the context of routine care from 2014 to 2019. For all premature infants and neonates with neonatal sepsis, the neonatal and maternal microbiological findings were examined to see if there was a match.

Results

During the study period, a total of 948 premature or newborn infants were identified as having a neonatal infection. Among all of the premature or newborn infants, 209 (22%) met the diagnostic criteria for neonatal sepsis; of these, 157 were premature births and 52 were full-term births. We evaluated the microbiological findings for these 209 mother and child pairs. No pathogens were detected in 27 out of 157 mothers of premature infants (17.1%) and in 31 out of 52 mothers of full-term infants (59.6%). In the premature infant group there were pairs with matching pathogens in 30 out of 130 cases (23.1%, 95% CI: 16.1-31.3), and in the full-term infant group there was a match in 4 out of 21 cases (19%, 95% CI: 5.4-41.9). The number needed to test to have a 90% probability of success for pathogen detection varies between 9 and 11 in the most favorable case and 26 and 32 in the least favorable case, depending on the evaluation method.

Conclusion

In cases of neonatal sepsis, the sepsis-causing pathogen was successfully detected through prior analysis of a maternal smear in 7% of full-term infants and in 19% of premature infants. The number needed to test was relatively high in all groups. The value of maternal smears for identifying neonatal sepsis-causing pathogens needs to be critically questioned.

Comparison of proposed National Institute of Child Health and Human Development panel recommendations with newborn sepsis risk calculator in term neonates exposed to maternal chorioamnionitis

BACKGROUND

Maternal chorioamnionitis (MC) is one of the major risk factors for early-onset neonatal sepsis. Kaiser sepsis risk calculator (SRC) is a validated risk assessment tool for such newborns. The National Institute of Child Health and Human Development (NICHD) workshop on MC has proposed a risk assessment algorithm. The objective of the study was to compare the reduction in antibiotic use in newborns treated with SRC and NICHD algorithm and determine the antibiotic use correlation between them.

METHODOLOGY

A retrospective chart review was performed on newborns born at ≥ 37 weeks to mothers with MC during the years 2018-2020. The same cohort of newborns was evaluated using SRC and NICHD algorithm to determine whether treatment with antibiotics could have been avoided in some patients. The data were analyzed using a t-test, Chi-square test, and ANOVA.

RESULTS

During the study period, 101 newborns were born to mothers with chorioamnionitis and received antibiotics. When the newborns were assessed using the SRC, only 16/101 (15.84%) would have received treatment. When NICHD algorithm was applied to the same cohort 71/101 (70.30%) newborns would have received treatment. The two approaches agreed in their assessment for treatment or observation only in 44/101 (43.56%) of the cases. The NICHD treatment group had a higher incidence of chorioamnionitis as seen in placental pathology (94.37% vs. 75.00% for Kaiser, p-0.015). The SRC treatment group however had newborns with significantly lower Apgar score at 1 min (8.21 vs 6.63, p-0.006) and 5-minute (8.69 vs 8.00, p-0.019) and had significantly higher supplemental oxygen requirements at admission (62.50% vs. 21.13%, p < 0.001).

CONCLUSION

Both SRC and NICHD algorithms expose fewer newborns to antibiotics; however, they differ in the number of newborns that would require antibiotics. Ventilation assistance and lower Apgar scores were associated with higher probability of antibiotic administration.

The PI3K-Akt pathway is a multifaceted regulator of the macrophage response to diverse group B Streptococcus isolates

Group B Streptococcus (GBS), also known as Streptococcus agalactiae, is a common member of the microbial flora in healthy individuals. However, problems may arise when GBS-colonized mothers become pregnant. GBS may be transferred from a colonized mother to her newborn or developing fetus, which may result in complications such as miscarriage, pre-term birth, meningitis, pneumonia, or sepsis. Macrophages play an especially important role in the fetal and newborn response to GBS due to the limited development of the adaptive immune system early in life. The goal of this study was to expand what is currently known about how GBS manipulates macrophage cell signaling to evade the immune system and cause disease. To this end, we investigated whether the PI3K-Akt pathway was involved in several key aspects of the macrophage response to GBS. We explored whether certain GBS strains, such as sequence type (ST)-17 strains, rely on this pathway for the more rapid macrophage uptake they induce compared to other GBS strains. Our findings suggest that this pathway is, indeed, important for macrophage uptake of GBS. Consistent with these findings, we used immunofluorescence microscopy to demonstrate that more virulent strains of GBS induce more actin projections in macrophages than less virulent strains. Additionally, we explored whether PI3K-Akt signaling impacted the ability of GBS to survive within macrophages after phagocytosis and whether this pathway influenced the survival rate of macrophages themselves following GBS infection. The PI3K-Akt pathway was found to promote the survival of both macrophages and intracellular GBS following infection. We also observed that inhibition of the PI3K-Akt pathway significantly reduced GBS-mediated activation of NFκB, which is a key regulator of cell survival and inflammatory responses. Overall, these insights into strain-dependent GBS-mediated manipulation of the PI3K-Akt pathway and its downstream targets in infected macrophages may provide new insights for the development of diagnostic and therapeutic tools to combat severe GBS disease.

Mild/asymptomatic COVID-19 in unvaccinated pregnant mothers impairs neonatal immune responses

Maternal SARS-CoV-2 infection triggers placental inflammation and alters cord blood immune cell composition. However, most studies focus on outcomes of severe maternal infection. Therefore, we analyzed cord blood and chorionic villi from newborns of unvaccinated mothers who experienced mild/asymptomatic SARS-CoV-2 infection during pregnancy. We investigated immune cell rewiring using flow cytometry, single-cell RNA sequencing, and functional readouts using ex vivo stimulation with TLR agonists and pathogens. Maternal infection was associated with increased frequency of memory T and B cells and nonclassical monocytes in cord blood. Ex vivo T and B cell responses to stimulation were attenuated, suggesting a tolerogenic state. Maladaptive responses were also observed in cord blood monocytes, where antiviral responses were dampened but responses to bacterial TLRs were increased. Maternal infection was also associated with expansion and activation of placental Hofbauer cells, secreting elevated levels of myeloid cell-recruiting chemokines. Moreover, we reported increased activation of maternally derived monocytes/macrophages in the fetal placenta that were transcriptionally primed for antiviral responses. Our data indicate that even in the absence of vertical transmission or symptoms in the neonate, mild/asymptomatic maternal COVID-19 altered the transcriptional and functional state in fetal immune cells in circulation and in the placenta.

Association of delivery risk phenotype with early-onset sepsis in preterm infants

OBJECTIVE

To determine delivery risk phenotype-specific incidence of early-onset sepsis (EOS) among preterm infants.

STUDY DESIGN

Retrospective cohort study of infants born <35 weeks' gestation at four perinatal centers during 2017-2021. Infants were classified into one of six delivery risk phenotypes incorporating delivery mode, presence of labor, and duration of rupture of membranes (ROM). The primary outcome was EOS incidence within the overall cohort and each risk phenotype.

RESULTS

Among 2937 preterm infants, 21 had EOS (0.7%, or 7.1 cases/1000 preterm infants). The majority of EOS cases (13/21, 62%) occurred in the setting of prolonged ROM ≥ 18 h, with a phenotype incidence of 23.8 cases/1000 preterm infants. There were no EOS cases among infants born by cesarean section without ROM (with or without labor), nor via cesarean section with ROM < 18 h without labor.

CONCLUSION

Delivery risk phenotyping may inform EOS risk stratification in preterm infants.

Risk and diagnostic factors and therapy outcome of neonatal early onset sepsis in ICU patients of Saudi Arabia: a systematic review and meta analysis

Background

Neonatal early onset sepsis (NEOS) is a serious and potentially life-threatening condition affecting newborns within the first few days of life. While the diagnosis of NEOS was based on clinical signs and symptoms in the past, recent years have seen growing interest in identifying specific diagnostic factors and optimizing therapy outcomes. This study aims to investigate the diagnostic and risk factors and therapy outcomes of neonatal EOS in ICU patients in Saudi Arabia, with the goal of improving the management of neonatal EOS in the country.

Methods

This method outlines the protocol development, search strategy, study selection, and data collection process for a systematic review on neonatal early onset sepsis in Saudi Arabian ICU patients, following the PRISMA 2020 guidelines. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) is a well-established guideline that provides a framework for conducting systematic reviews and meta-analyses in a transparent and standardized manner. It aims to improve the quality and reporting of such research by ensuring clear and comprehensive reporting of study methods, results, and interpretations. The search strategy included electronic databases (PubMed, Embase, Google Scholar, Science Direct, and the Cochrane Library) and manual search of relevant studies, and data were extracted using a standardized form.

Results

The systematic review included 21 studies on neonatal sepsis in Saudi Arabia, with varying study designs, sample sizes, and prevalence rates of sepsis. Group B streptococcus and E. coli were the most commonly isolated pathogens. Various diagnostic factors and risk factors were reported, including hematological parameters, biomarkers, and blood cultures. The quality of the included studies was assessed using the Newcastle-Ottawa Scale and Joanna Briggs Institute critical checklist.

Conclusions

The review identified a number of risk and diagnostic factors and therapy outcomes for neonatal sepsis. However, most of the studies were having small scale cohort groups. Further research with controlled study designs is needed to develop effective prevention and management strategies for neonatal sepsis in Saudi Arabia.

Establishment of a prediction model for histological chorioamnionitis and its association with outcomes of premature infants

Aim

This study aims to construct a prediction model for histological chorioamnionitis (HCA) and analyze the associations between the predicted risk of HCA and adverse outcomes in preterm infants.

Methods

In total, 673 subjects were included in this cohort study and divided into HCA group (n = 195) and non-HCA group (n = 478). A stepwise method was used to screen the predictors for HCA, binary logistic regression was used to construct the prediction model, and the associations between the predicted risk of HCA and adverse outcomes were analyzed.

Results

HCA occurred in 195 patients, accounting for 29.0%. The sensitivity of the prediction model was 0.821 [95% confidence interval (CI): 0.767-0.874)], the specificity was 0.684 (95% CI: 0.642-0.726), the positive predictive value was 0.514 (0.459-0.570), the negative predictive value was 0.903 (95% CI: 0.873-0.934), the area under the curve was 0.821 (95% CI: 0.786-0.855), and the accuracy was 0.724 (95% CI: 0.690-0.757). The predicted risk of HCA was associated with a higher risk of bronchopulmonary dysplasia (BPD) [odds ratio (OR) = 3.48, 95% CI: 1.10-10.95)], sepsis (OR = 6.66, 95% CI: 2.17-20.43), and neonatal infections (OR = 9.85, 95% CI: 3.59-26.98), but not necrotizing enterocolitis (OR = 0.67, 95% CI: 0.24-1.88), retinopathy of prematurity (OR = 1.59, 95% CI: 0.37-6.85), and brain damage (OR = 1.77, 95% CI: 0.82-3.83). After adjusting for confounders including gestational week at birth and birth weight, the risk of neonatal infections (OR = 5.03, 95% CI: 2.69-9.41) was increased in preterm infants' exposure to HCA.

Conclusion

The model showed good predictive performance for identifying pregnant women with a higher risk of HCA. In addition, HCA was associated with the risk of BPD, sepsis, and infections in neonates.

Categorical Risk Stratification for Neonatal Early Onset Sepsis using Suspected Intraamniotic Infection and the Newborn Exam

Objective

To determine test characteristics of categorical risk stratification for early onset sepsis (EOS) using maternal criteria for suspected intraamniotic infection (IAI) and/or newborn exam and compare them to the EOS calculator.

Study Design

Retrospective 1:3 case-control study of late preterm/term infants with bacterial culture growth obtained <72 hours of life. For categorical approach, infants of mothers with suspected IAI or equivocal/ill appearing were presumed high-risk for EOS and blood culture obtained. For calculator, estimated probability of EOS and care recommendations were recorded from online calculator. Test characteristics were compared with McNemar's test; recommendation for blood culture was considered a "positive" test.

Result

52 cases and 172 controls were included. Compared to the calculator, the categorical approach had higher sensitivity 90%(95%CI:79-96%) vs 67% (95%CI:54-79%) but lower specificity 85%(95%CI:78-89%) vs. 92%(95%CI:87-96%). 10% of cases were not identified by either.

Conclusion

A categorical approach using suspected IAI/newborn exam offers good EOS discrimination and is comparable to the calculator.

Antibiotic therapy and necrotizing enterocolitis

Antibiotic therapy remains a cornerstone of treatment of both medical and surgical presentations of necrotizing enterocolitis (NEC). However, guidelines regarding the administration of antibiotics for the treatment of NEC are lacking and practices vary amongst clinicians. Although the pathogenesis of NEC is unknown, there is consensus that the infant gastrointestinal microbiome contributes to the disease. The presumed connection between dysbiosis and NEC has prompted some to study whether early prophylactic enteral antibiotics can prevent NEC. Yet others have taken an opposing approach, studying whether perinatal antibiotic exposure increases the risk of NEC by inducing a state of dysbiosis. This narrative review summarizes what is known about antibiotics and their association with the infant microbiome and NEC, current antibiotic prescribing practices for infants with medical and surgical NEC, as well as potential strategies to further optimize the use of antibiotics in this population of infants.

Conservative management of newborns with 35 weeks or more of gestational age at risk for early-onset sepsis: a Brazilian cohort study

OBJECTIVE

To evaluate the conservative management of newborns born at ≥35 weeks of gestational age, at risk for early-onset neonatal sepsis (EOS).

METHODS

Retrospective, analytic cohort study (2016 to 2019), including newborns ≥35 weeks of gestational at risk of EOS, asymptomatic at birth, managed conservatively in full rooming-in: serial physical examination and clinical observation for at least 48 h. They were classified into three groups, according to the clinical course: asymptomatic (group A), symptomatic for other reasons (group B), and with sepsis (group C). Risk factors, clinical signs and differential diagnoses of sepsis, length of stay, and discharge conditions were evaluated.

RESULTS

The authors evaluated 769 asymptomatic newborns at risk of EOS. (mean birth weight 2999 ± 485 g and gestational age 37.6 ± 1.7 weeks, respectively) corresponding to 12.2% of rooming-in admissions. The most prevalent risk factors were colonization by Group B Streptococcus (29%), prolonged rupture membrane duration (21.9%) and preterm labor (21.4%). Most of all of them (53.9%) remained asymptomatic (group A). Group B corresponded for 45.3%, and the most common clinical signs were hypothermia (24.5%), tremors (8.7%) and vomiting (8%). Environmental dysthermia (50.7%), prematurity (20.0%), and feeding intolerance (15.7%) were common in Group B. Laboratory tests were performed in 3.5%. Five patients (one confirmed) comprised group C (0.8/1,000 live births). There were no deaths. The median length of stay was 64 h (IQR 50-93).

CONCLUSION

The rate of clinical/confirmed EOS was low. Most of the symptomatic patients only needed clinical evaluation to rule out sepsis. Management was shown to be safe.

Early-onset neonatal sepsis in the Paris area: a population-based surveillance study from 2019 to 2021

BACKGROUND

Early-onset neonatal sepsis (EOS) is a rare condition but an important cause of severe morbidity and mortality in neonates.

METHODS

This is a prospective observational study in neonates born at ≥34 weeks of gestation (WG). The primary endpoint was EOS, defined by isolation of pathogenic species from blood culture and/or cerebrospinal fluid culture within 72 hours after birth. Data on EOS were collected exhaustively from all maternity wards in Paris area (April 2019-March 2021).

RESULTS

108 EOS were recorded (annual incidence, 0.32 per 1000 live births; 95% CI 0.26 to 0.38). In term infants, the most frequent pathogens were group B Streptococcus (GBS) (n=47) and Escherichia coli (n=20); in late preterm infants, the most frequent pathogens were E. coli (n=15) and GBS (n=7). Fifteen meningitis cases were diagnosed. Five E. coli strains (14%) were resistant to both amoxicillin and gentamicin, which is an empiric treatment for EOS. Of the 54 infants with GBS infections, 35 were born from mothers with negative GBS prepartum screening test and 8 from mothers with no screening. Two deaths were reported, both in term infants (Proteus mirabilis and E. coli).

CONCLUSION

In neonates ≥34 WG born in the Paris area, GBS was twice as frequent as E. coli in term infants. EOS was six times more frequent in late preterm than in term infants and was due to E. coli in 60% of cases. Prevention of GBS EOS and empiric antibiotic treatment of EOS could be improved.

How to assess early-onset neonatal sepsis? Comparison of three detection strategies

INTRODUCTION

Early-onset neonatal sepsis (EONS) can cause significant morbidity and mortality, especially if it is not detected early. Given the decrease in its incidence in the past few decades, it is important to find a balance between reducing the use of diagnostic tests and continuing to detect affected patients. We compared 3 detection strategies in patients with risk factors (RFs) for infection: laboratory screening (S1), the Neonatal Sepsis Risk Calculator (S2) and clinical observation (S3).

PATIENTS AND METHODS

Retrospective observational study in neonates born at 34 weeks of gestation or later and with RFs or symptoms compatible with EONS. We analysed outcomes in our unit with the use of laboratory screening (S1) and compared them with the other two strategies (S2 and S3) to contemplate whether to modify our protocol.

RESULTS

The study included 754 patients, and the most frequent RFs were prolonged rupture of membranes (35.5%) and maternal colonization by Streptococcus agalactiae (38.5%). Strategies S2 and S3 would decrease the performance of laboratory tests (S1, 56.8% of patients; S2, 9.9%; S3, 22.4%; P < 0.01), hospital admissions (S1, 11%; S2, 6.9%; S3, 7.9%; P < 0.01) and the use of antibiotherapy (S1, 8.6%; S2, 6.7%; S3, 6.4%; P < 0.01). Sepsis was diagnosed in 13 patients, and it would have been detected with S2 and S3 except in 1 patient who had asymptomatic bacteriemia by Enterococcus faecalis. No patient with mild and self-limited symptoms in whom antibiotherapy was not started received a diagnosis of sepsis later on.

CONCLUSION

Close clinical observation seems to be a safe option and could reduce the use of diagnostic tests, hospital admission and unnecessary antibiotherapy. The watchful waiting approach in patients with mild and self-limiting symptoms in the first hours post birth does not appear to be associated with failure to identify sepsis.

What's new in the management of neonatal early-onset sepsis?

The expert guidelines highlighted in this review provide an evidence-based framework for approaching at-risk infants and allow for a more limited and standardised approach to antibiotic use. While these guidelines have significantly reduced antibiotic utilisation worldwide, optimally each unit would individualise their approach to early onset sepsis (EOS) based on the neonatal population they serve and available resources. As advancements in EOS research continue and limitations with sepsis prediction tools are addressed, it is inevitable that our risk stratification and management guidelines will become more precise.

Quality Improvement Through Nurse-initiated Kaiser Sepsis Calculator at a County Hospital

BACKGROUND AND OBJECTIVES

Suspected early onset sepsis drives most antibiotic use in the newborn nursery. The Kaiser Sepsis Calculator (KSC) is a validated tool that safely decreases laboratory evaluation and antibiotic administration in infants aged ≥34 weeks. Our quality improvement aim was a nurse-initiated, KSC-based program to decrease blood cultures (BCx) and complete blood counts (CBC) by 10% from March 2021 to October 2021 among chorioamnionitis-exposed infants born ≥35 weeks' gestation. A secondary aim was to decrease antibiotic administration by 10%.

METHODS

The KSC was implemented for infants at University Health, a county hospital affiliate of the University of Texas Health Science Center San Antonio, with a level I nursery and level IV NICU. The multidisciplinary project included pediatric hospitalists, neonatologists, family practitioners, maternal-fetal medicine physicians, fellows, residents, and nurses. All infants born 6 months before (August 2020-January 2021) and 7 months after protocol implementation (March 2021-September 2021) were analyzed.

RESULTS

A total of 53 chorioamnionitis-exposed infants were included from the preintervention period and 51 from the postintervention period. CBC utilization decreased from 96% to 27%, BCx utilization decreased from 98% to 37%, and antibiotic utilization fell from 25% to 16%. In no cases were antibiotics prescribed against the KSC, and to our knowledge, no early onset sepsis diagnoses or infection-related hospital readmissions were missed.

CONCLUSIONS

The multidisciplinary implementation of the KSC led to a reduction in testing, exceeding our initial goal. A nurse-initiated protocol reduced BCx, CBC, and antibiotic utilization among chorioamnionitis-exposed infants.

Association of clinical signs of chorioamnionitis with histological chorioamnionitis and neonatal outcomes

BACKGROUND

Chorioamnionitis is a risk factor for fetal and neonatal outcomes. Therefore, predicting histological chorioamnionitis (HCA) and neonatal outcomes using clinical parameters could be helpful in management and preventing morbidities.

OBJECTIVE

To determine if parameters of clinical chorioamnionitis (CCA) would be associated with HCA and neonatal outcomes.

STUDY DESIGN

In this cohort study using a retrospective design, we analyzed the performance of signs of CCA in predicting HCA, and neonatal outcomes. Data were extracted from the electronic health record for all neonates with documented CCA delivered at our institution from 2011 to 2016. We compared our findings based on the old ACOG definition of CCA and the new definition released in 2017 - maternal fever plus any of fetal tachycardia, maternal leukocytosis, and purulent vaginal discharge. Maternal tachycardia and uterine tenderness were removed from the new criteria. Neonatal laboratory samples on admission, 12 h and 24 h were used to define the three time points of neonatal suspected sepsis.

RESULTS

There were 530 mothers-infant dyads with chorioamnionitis. Seventy-three were preterm, and 457 were term. Eighty-eight percent of the preterm mothers had CCA, and HCA was present in 62.5% of 72 preterm placentas. Preterm infants with placental HCA significantly had lower birth weight, gestational age, placental weight, and more infants with lower 5-minute Apgar scores, compared to those with no HCA. In preterm infants, maternal urinary tract infection was significantly associated with decreased odds for HCA (OR 0.22, CI 0.10 - 0.71). More preterm babies with suspected sepsis criteria at the 3 time points had HCA (all p ≤ .01). In the term cohort, 95.4% and 65.6% had CCA and HCA, respectively. In term infants (n = 457), maternal leukocytosis (p = .002) and prolonged rupture of membranes (PROM; p = 002) were associated with HCA. Suspected sepsis was associated with PROM (p = .04), HCA (p = .0001), and maternal leukocytosis (p ≤ .05) in at least 1 of the 3 time points.

CONCLUSION

Though maternal leukocytosis was significantly associated with the presence of HCA in the term cohort, there were no CCA criteria that accurately predicted presence of HCA in either the preterm or the term infants.

Analysis of predictive parameters for extubation in very low birth weight preterm infants

BACKGROUND

Mechanical ventilation is the primary treatment for preterm infants with respiratory failure. Prolonged intubation may lead to complications; thus, early extubation is desirable. No standard criteria exist for determining the appropriateness of extubating very-low-birth-weight (VLBW) infants. This study explored the predictors of successful extubation in preterm VLBW infants.

METHODS

This retrospective cohort study included 60 preterm VLBW infants who underwent their first extubation in the neonatal intensive care unit in a regional hospital in Hsinchu, Taiwan, between January 2017 and November 2020. Successful extubation was defined as having no requirement of reintubation within 3 days of extubation. Potentially predictive variables, including demographics, prenatal characteristics, and ventilator parameters were compared between a successful extubation group and failed extubation group.

RESULTS

Of the 60 infants, 47 (78.33%) underwent successful extubation. The successful extubation group had higher Apgar scores at 1 (7 vs. 6, P = 0.02) and 5 min (9 vs. 7, P = 0.007) than those of the failed extubation group. Ventilator inspiratory pressure and mean airway pressure were significantly lower at 24, 16, 8, and 1 h before extubation and upon its completion in the successful extubation group. The areas under a number of the receiver operating characteristic curve curves in this study were moderate, specifically, 0.72, 0.74, and 0.69. Statistical analysis revealed an association between ventilator parameters before 1 h extubation (IP > 17.5cmH₂O, MAP >7.5 cmH₂O, RSS >1.82) and extubation failure (odds ratio 1.73, 2.27, 2.46 and 95% confidence interval:1.16-2.6, 1.26-4.08, 1.06-5.68, respectively).

CONCLUSION

Higher Apgar scores at birth, lower ventilator inspiratory pressure, and mean airway pressure 24, 16, 8, and 1 h and 1 h RSS prior to extubation are associated with successful extubation in VLBW preterm infants.

Reducing antibiotic use in asymptomatic term infants exposed to maternal chorioamnionitis: Predictive role of sepsis risk calculator

AIM

The sepsis risk calculator (SRC) has been shown to reduce empirical antibiotic usage in neonates at risk of early-onset sepsis without increasing adverse clinical outcomes. However, its use for categorising and improving identification of at-risk neonates exposed to chorioamnionitis in the local population has not been reported. This study compares the management guided by the SRC to our unit's clinical practice of administering empirical antibiotics to all term neonates (born ≥37 weeks gestation), symptomatic and asymptomatic, who were exposed to chorioamnionitis, and evaluates the performance of the SRC in managing asymptomatic term neonates exposed to chorioamnionitis.

METHODS

This single-centre retrospective study identified 178 eligible term neonates exposed to chorioamnionitis over a 17-month study period. Relevant demographic and clinical information on the mother-infant dyad was collected. The SRC was executed retrospectively in the study cohort. Descriptive statistics were used for reporting the findings.

RESULTS

The mean gestational age was 39 (standard deviation, SD 1) weeks, and the mean birth weight was 3472 (SD 482) g. Of the 178 neonates, 136 (76%) were asymptomatic and received empirical antibiotic therapy for 2 days (mean). Based on management recommendations from the SRC, empirical antibiotic therapy could have been avoided in 98% of asymptomatic neonates; 88% could have been managed by observation alone, avoiding mother-infant separation. No neonate died or had a positive blood culture result.

CONCLUSIONS

The SRC could reduce antibiotic exposure in asymptomatic neonates exposed to chorioamnionitis. It could assist clinicians to categorise risk in neonates exposed to chorioamnionitis.

Neonatal infections: Insights from a multicenter longitudinal research collaborative

For more than 30 years, the Neonatal Research Network (NRN) has conducted studies addressing the epidemiology of neonatal infections, including incidence, microbiology, maternal and neonatal risk factors, associated clinical findings, and outcomes. These studies have provided clinicians and policymakers critical data needed to inform national guidance for infection risk assessment and support daily practice. Further, NRN studies have prompted research into optimal approaches to infection diagnosis, treatment, and antimicrobial stewardship. In this article, we summarize the key findings of NRN infection-related studies, with an emphasis on those published in 2000 or later.

Management of neonates with 35 weeks of gestational age or more with infectious risk factors at birth: opportunities for improvement

OBJECTIVES

The Northern California Kaiser-Permanente Neonatal Sepsis Risk Calculator (SRC) has proved to be safe and effective in reducing laboratory tests, hospital admissions, and administration of antibiotics to patients at risk of early-onset neonatal sepsis (EONS). Many studies have focused on maternal chorioamnionitis as the principal risk factor for EONS. We wanted to know if the use of the SRC could be equally efficient in the context of several other infectious risk factors (IRF), in addition to chorioamnionitis, such as intrapartum maternal fever, GBS colonization and/or prolonged rupture of membranes (PROM).

METHODS

Systematic study of neonates with ≥35 weeks gestational age (GA), born in our tertiary university hospital during a period of 18 months. Patients were retrospectively assessed with the SRC and its recommendations were compared with the actual management. A bivariate analysis of perinatal interventions, and outcomes was performed.

RESULTS

A total of 5,885 newborns were born during the study period and 1783 mothers (31%) had at least one IRF. The incidence of culture-proven EONS was 0.5‰. The use of the SRC would have reduced laboratory evaluations (CBC and CRP) from 56.2 to 23.3%, and blood cultures, hospital admissions and antibiotic therapy from 22.9 to 15.5%, 17.8 and 7.6%, respectively. The management based on patients' symptoms would have shown a reduction to 7.5% in all the outcomes of interest.

CONCLUSIONS

Both, the SRC and the management based on clinical findings, are safe and efficient to reduce the number of analytical studies, hospital admissions and administration of antibiotics to neonates with IRF.

Preterm delivery and its associated factors among mothers in Bangladesh: survey in Rajshahi district

OBJECTIVES

Preterm delivery (PD) is a worldwide health burden particularly in low-income and middle-income countries such as Bangladesh. It is a key indicator of neonatal mortality and a risk of morbidity in later life. This study aimed to determine the prevalence of PD and its associated factors among mothers in Northern region of Bangladesh.

SETTING AND PARTICIPANTS

Multistage sampling technique was used to select samples covering all the population from 9 Upazilas in Rajshahi district with 233 community clinics. A total of 540 mothers and their under-5 children were enrolled for the study. Descriptive statistics, χ² test and logistic regression model were used to analyse the data.

RESULTS

Among all live births, the prevalence of PD was found to be 14.6%. Multiple binary logistic regression model suggested five factors of PD: (1) mothers who used contraceptive pill had lower chance of PD (p<0.05); (2) mothers with high fever during pregnancy period were more likely to have PD (p<0.05); (3) mothers who did not receive antenatal care service less than four times during pregnancy period had higher chance of PD (p<0.01); (4) mothers first married before 18 years who were more likely to have PD (p<0.01); (5) PD delivered mothers had more chance to get low birth weight children (p<0.05). In addition, unadjusted model demonstrated that mothers delivered first baby before their age<20 years were more risk to get PD (p<0.05).

CONCLUSION

Approximately one in seven infants was born preterm in our study area. Family planning method, number of antenatal care visit, mothers' age at marriage and high fever during pregnancy were the most important predictors of PD, these factors could be considered to reduce PD among Bangladeshi mothers. PD risk could be reduced by counselling and encouraging women to take antenatal care facilities from trained health providers.

Prenatal exposure to multiple metallic and metalloid trace elements and the risk of bacterial sepsis in extremely low gestational age newborns: A prospective cohort study

BACKGROUND

Prenatal exposures to metallic and metalloid trace elements have been linked to altered immune function in animal studies, but few epidemiologic studies have investigated immunological effects in humans. We evaluated the risk of bacterial sepsis (an extreme immune response to bacterial infection) in relation to prenatal metal/metalloid exposures, individually and jointly, within a US-based cohort of infants born extremely preterm.

METHODS

We analyzed data from 269 participants in the US-based ELGAN cohort, which enrolled infants delivered at <28 weeks' gestation (2002-2004). Concentrations of 8 trace elements-including 4 non-essential and 4 essential-were measured using inductively coupled plasma tandem mass spectrometry in umbilical cord tissue, reflecting in utero fetal exposures. The infants were followed from birth to postnatal day 28 with bacterial blood culture results reported weekly to detect sepsis. Discrete-time hazard and quantile g-computation models were fit to estimate associations for individual trace elements and their mixtures with sepsis incidence.

RESULTS

Approximately 30% of the extremely preterm infants developed sepsis during the follow-up period (median follow-up: 2 weeks). After adjustment for potential confounders, no trace element was individually associated with sepsis risk. However, there was some evidence of a non-monotonic relationship for cadmium, with hazard ratios (HRs) for the second, third, and fourth (highest) quartiles being 1.13 (95% CI: 0.51-2.54), 1.94 (95% CI: 0.87-4.32), and 1.88 (95% CI: 0.90-3.93), respectively. The HRs for a quartile increase in concentrations of all 8 elements, all 4 non-essential elements, and all 4 essential elements were 0.92 (95% CI: 0.68-1.25), 1.19 (95% CI: 0.92-1.55), and 0.77 (95% CI: 0.57-1.06). Cadmium had the greatest positive contribution whereas arsenic, copper, and selenium had the greatest negative contributions to the mixture associations.

CONCLUSIONS

We found some evidence that greater prenatal exposure to cadmium was associated with an increased the risk of bacterial sepsis in extremely preterm infants. However, this risk was counteracted by a combination of arsenic, copper, and selenium. Future studies are needed to confirm these findings and to evaluate the potential for nutritional interventions to prevent sepsis in high-risk infants.

Clinical and laboratory factors associated with neonatal sepsis mortality at a major Vietnamese children's hospital

Sepsis is a major cause of neonatal mortality and children born in low- and middle-income countries (LMICs) are at greater risk of severe neonatal infections than those in higher-income countries. Despite this disparity, there are limited contemporaneous data linking the clinical features of neonatal sepsis with outcome in LMICs. Here, we aimed to identify factors associated with mortality from neonatal sepsis in Vietnam. We conducted a prospective, observational study to describe the clinical features, laboratory characteristics, and mortality rate of neonatal sepsis at a major children's hospital in Ho Chi Minh City. All in-patient neonates clinically diagnosed with probable or culture-confirmed sepsis meeting inclusion criteria from January 2017 to June 2018 were enrolled. We performed univariable analysis and logistic regression to identify factors independently associated with mortality. 524 neonates were recruited. Most cases were defined as late-onset neonatal sepsis and were hospital-acquired (91.4% and 73.3%, respectively). The median (IQR) duration of hospital stay was 23 (13-41) days, 344/524 (65.6%) had a positive blood culture (of which 393 non-contaminant organisms were isolated), and 69/524 (13.2%) patients died. Coagulase-negative staphylococci (232/405; 57.3%), Klebsiella spp. (28/405; 6.9%), and Escherichia coli (27/405; 6.7%) were the most isolated organisms. Sclerema (OR = 11.4), leukopenia <4,000/mm3 (OR = 7.8), thrombocytopenia <100,000/mm3 (OR = 3.7), base excess < -20 mEq/L (OR = 3.6), serum lactate >4 mmol/L (OR = 3.4), extremely low birth weight (OR = 3.2), and hyperglycaemia >180 mg/dL (OR = 2.6) were all significantly (p<0.05) associated with mortality. The identified risk factors can be adopted as prognostic factors for the diagnosis and treatment of neonatal sepsis and enable early risk stratification and interventions appropriate to reduce neonatal sepsis in LMIC settings.

A retrospective study of risk factors for early-onset neonatal sepsis with intrapartum maternal fever

Background

Intrapartum fever is a well-known risk factor for adverse perinatal outcomes. In this study, we evaluated the clinical features for intrapartum maternal fever and investigated the risk factors for neonatal early-onset sepsis (EOS) with intrapartum maternal fever.

Methods

This retrospective cohort study involved a total of 568 neonates born to mothers with intrapartum maternal fever (temperature peak ≥38 degree Celsius) in Hangzhou Women's Hospital from January 1st to December 31st, 2019. Neonates were assigned to the EOS and non-sepsis groups based on the diagnostic criteria for early-onset neonatal sepsis,. Demographic data, clinical information and laboratory test results were evaluated to assess the risk factors for EOS.

Results

A total of 568 neonates were included in this study, 84 of whom were diagnosed with EOS. The EOS group was significantly different from the non-sepsis group in 11 items including the both white blood cell (WBC) count and C-reactive protein (CRP) level of the mother before delivery (p < 0.05). A logistic regression analysis revealed that a high maternal WBC count before delivery (OR = 3.261, p = 0.019) and a maternal histological chorioamnionitis (HCA) diagnosis (OR = 5.608, p = 0.002) were independent risk factors for EOS. The optimal cut-off value for WBC (before delivery) was 16.75 × 10*⁹/L for EOS, according to receiver operating characteristic analysis (area under curve was 0.821).

Conclusions

Elevated prenatal maternal WBC counts and maternal HCA diagnosis are both independently associated with EOS. Prenatal maternal WBC counts can be used as a sensitive indicator to predict EOS early.

Use of a Quality Scorecard to Enhance Quality and Safety in Community Hospital Newborn Nurseries

OBJECTIVE

To implement a quality improvement (QI) scorecard as a tool for enhancing quality and safety efforts in level 1 and 2 community hospital nurseries affiliated with Nationwide Children's Hospital.

STUDY DESIGN

A QI scorecard was developed for data collection, analytics, and reporting of neonatal quality metrics and cross-sector collaboration. Newborn characteristics were included for risk stratification, as were clinical and process measures associated with neonatal morbidity and mortality. Quality and safety activities took place in community hospital newborn nurseries in Ohio, and education was provided in both online and in-person collaborations, followed by local team sessions at partner institutions. Baseline (first 12 months) and postbaseline comparisons of clinical and process measures were analyzed by logistic regression, adjusting for potential confounders.

RESULTS

In logistic regression models, at least 1 center documented improvements in each of the 4 process measures, and 3 of the 4 centers documented improvements in compliance with glucose checks obtained within 90 minutes of birth among at-risk infants.

CONCLUSION

Collaborative QI projects led to improvements in perinatal metrics associated with important outcomes. Formation of a center-driven QI scorecard is feasible and provides community hospitals with a framework for collecting, analyzing, and reporting neonatal QI metrics.

Infections in the NICU: Neonatal sepsis

Neonatal infections remain an important cause of neonatal morbidity and mortality worldwide. Neonatal sepsis is a systemic infection that can be classified as early-onset or late-onset pending the timing of presentation. The pathophysiology and causative pathogens of neonatal sepsis vary, with early-onset sepsis being associated with a vertically transmitted infection from mother to neonate versus late onset sepsis being commonly associated with nosocomial infections. The signs and symptoms of neonatal sepsis mimic those associated with prematurity, making timely diagnosis difficult for treating clinicians. The management of neonatal sepsis is centered around obtaining adequate culture data and initiation of broad-spectrum parenteral antibiotics. Controversies surrounding the management of neonatal sepsis include the administration of empiric antibiotics, given recent clinical studies associating early antibiotic use with clinical sequelae such as late-onset sepsis, necrotizing enterocolitis, and death in the preterm, low-birthweight infant population.

The NICU Antibiotics and Outcomes (NANO) trial: a randomized multicenter clinical trial assessing empiric antibiotics and clinical outcomes in newborn preterm infants

Background

Early-onset sepsis is an important cause of neonatal morbidity and mortality in the preterm population. Infants perceived to be at increased risk for early-onset sepsis are often treated empirically with broad-spectrum antibiotics while awaiting confirmatory blood cultures, despite an overall incidence of early-onset sepsis of 2–3% among extremely-low-birthweight (ELBW) infants. Recent observational studies associate perinatal antibiotic use with an increased incidence of necrotizing enterocolitis, late-onset sepsis, and mortality among ELBW infants. Given currently available data and variability in clinical practice, we designed a prospective multi-institutional randomized controlled trial to determine the safety of early antibiotic use in ELBW infants.

Methods

The NICU Antibiotics and Outcomes (NANO) trial is a multicenter, double-blinded, randomized controlled trial. A sample of 802 ELBW preterm infants will undergo web-based stratified block randomization to receive empiric antibiotics (EA; ampicillin and gentamicin) or placebo during routine evaluation for early-onset sepsis. Participating sites will use preexisting institutional protocols for antibiotic dosage and duration. Infants born at participating sites with a gestational age of 29 weeks or less are eligible for enrollment. Exclusion criteria include maternal intrauterine infection, hemodynamic or respiratory instability, delivery by caesarean section for maternal indications without labor or prolonged rupture of membranes, and prior administration of antibiotics. The primary outcome is the composite incidence of necrotizing enterocolitis, late-onset sepsis, or death during participants’ index hospitalization. Maternal and infant samples will be collected longitudinally and assessed for differences in microbiome composition and diversity.

Discussion

The NANO trial is designed to compare the rate of adverse outcomes of EA use at birth versus placebo in ELBW preterm infants. If EA at birth worsens clinical outcomes, then the results of the trial may help providers decrease antibiotic utilization in the NICU and subsequently decrease the incidence of complications associated with early antibiotic use in ELBW infants. If we instead find that EA improve outcomes, then the trial will validate a longstanding clinical practice that has not previously been supported by high-quality data. Future studies will assess long-term clinical and microbial outcomes in infants who received empiric antibiotics following delivery.

Trial registration

Trial registration data: June 25, 2019 NCT03997266.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06352-3.

Antimicrobial Stewardship at Birth in Preterm Infants: Not Just About a Decrease!

BACKGROUND

Early-onset sepsis results in increased morbidity and mortality in preterm infants. Antimicrobial Stewardship Programs (ASPs) address the need to balance adverse effects of antibiotic exposure with the need for empiric treatment for infants at the highest risk for early-onset sepsis.

METHODS

All preterm infants <34 weeks gestational age born during a 6-month period before (January 2017-June 2017) and a 6-month period after (January 2019-June 2019) implementation of ASP in May 2018 were reviewed. The presence of perinatal sepsis risk factors, eligibility for, versus treatment with initial empiric antibiotics was compared.

RESULTS

Our cohort comprised 479 infants with a mean of 30 weeks gestation and birth weight of 1400 g. Demographics were comparable, with more Cesarean section deliveries in the post-ASP cohort. Any sepsis risk factor was present in 73.6% versus 68.4% in the pre- versus post-ASP cohorts (P = 0.23). Fewer infants were treated with antibiotics in the later cohort (60.4%) compared with the earlier cohort (69.7%; P = 0.04). Despite the presence of risk factors (preterm labor in 93% and rupture of membranes in 60%), 42% of infants did not receive initial antibiotics. Twenty percent with no perinatal sepsis risk factors were deemed low-risk and not treated.

CONCLUSIONS

Implementation of a neonatal ASP decreased antibiotic initiation at birth. Antibiotic use decreased (appropriately) in the subgroup with no perinatal sepsis risk factors. Of concern, some infants were not treated despite risk factors, such as preterm labor/rupture of membrane. Neonatal ASP teams need to be aware of potentially unintended consequences of their initiatives.

Neonatal early-onset sepsis calculator safety in an Australian tertiary perinatal centre

AIM

To determine if any cases of culture-positive neonatal early-onset sepsis (EOS) would be missed using the neonatal EOS calculator, when compared with current guidelines and practices.

METHODS

Retrospective audit of all neonates born at ≥35 weeks and admitted to Royal Brisbane and Women's Hospital with EOS from January 2014 to December 2020. A missed case was defined as antibiotic therapy not being recommended within 24 h of birth. Management recommendations according to the neonatal EOS calculator were compared with current guidelines and current practices.

RESULTS

There were significantly more missed cases using the neonatal EOS calculator compared to the current guideline and current management groups. Using the neonatal EOS calculator, 11 neonates (35%, 95% confidence interval 19.2-54.6%) would not have received antibiotics by 24 h of age. In comparison, only one neonate (3%, 95% confidence interval 0.1-16.7%) would not have received antibiotics by 24 h of age using the current guidelines. In terms of the current practice in the cohort of patients, two neonates (6%) did not receive antibiotics by 24 h of age.

CONCLUSIONS

The significantly higher rate of missed cases using the neonatal EOS calculator compared with current guidelines and practice supports the concerns many neonatologists have regarding safety of the neonatal EOS calculator.

Delivery Characteristics and the Risk of Early-Onset Neonatal Sepsis

BACKGROUND AND OBJECTIVES

Multiple strategies are used to identify newborn infants at high risk of culture-confirmed early-onset sepsis (EOS). Delivery characteristics have been used to identify preterm infants at lowest risk of infection to guide initiation of empirical antibiotics. Our objectives were to identify term and preterm infants at lowest risk of EOS using delivery characteristics and to determine antibiotic use among them.

METHODS

This was a retrospective cohort study of term and preterm infants born January 1, 2009 to December 31, 2014, with blood culture with or without cerebrospinal fluid culture obtained ≤72 hours after birth. Criteria for determining low EOS risk included: cesarean delivery, without labor or membrane rupture before delivery, and no antepartum concern for intraamniotic infection or nonreassuring fetal status. We determined the association between these characteristics, incidence of EOS, and antibiotic duration among infants without EOS.

RESULTS

Among 53 575 births, 7549 infants (14.1%) were evaluated and 41 (0.5%) of those evaluated had EOS. Low-risk delivery characteristics were present for 1121 (14.8%) evaluated infants, and none had EOS. Whereas antibiotics were initiated in a lower proportion of these infants (80.4% vs 91.0%, P < .001), duration of antibiotics administered to infants born with and without low-risk characteristics was not different (adjusted difference 0.6 hours, 95% CI [-3.8, 5.1]).

CONCLUSIONS

Risk of EOS among infants with low-risk delivery characteristics is extremely low. Despite this, a substantial proportion of these infants are administered antibiotics. Delivery characteristics should inform empirical antibiotic management decisions among infants born at all gestational ages.

Chorioamnionitis and neonatal outcomes

Chorioamnionitis or intrauterine inflammation is a frequent cause of preterm birth. Chorioamnionitis can affect almost every organ of the developing fetus. Multiple microbes have been implicated to cause chorioamnionitis, but "sterile" inflammation appears to be more common. Eradication of microorganisms has not been shown to prevent the morbidity and mortality associated with chorioamnionitis as inflammatory mediators account for continued fetal and maternal injury. Mounting evidence now supports the concept that the ensuing neonatal immune dysfunction reflects the effects of inflammation on immune programming during critical developmental windows, leading to chronic inflammatory disorders as well as vulnerability to infection after birth. A better understanding of microbiome alterations and inflammatory dysregulation may help develop better treatment strategies for infants born to mothers with chorioamnionitis.

Management of well appearing infants born to afebrile mothers with inadequate GBS prophylaxis: A retrospective comparison of the three approaches recommended by the COFN

BACKGROUND

There are three different approaches set forth by the Committee on the Fetus and Newborn (COFN) for managing asymptomatic neonates born to mothers with inadequate intrapartum antibiotic prophylaxis (IAP) for early-onset Group B Strep (GBS) infection. The first approach is that of categorical risk factor assessments, and recommends that asymptomatic infants born to afebrile mothers with inadequate IAP for GBS be monitored with clinical observation for 36-48 hours. The second approach recommends serial physical examinations and vital signs for 36-48 hours to closely monitor changes in clinical condition for all patients. The Kaiser Permanente EOS risk calculator (SRC) is an example of the third approach, a multivariate risk assessment, and it takes into consideration several perinatal risk factors. This multivariate risk assessment then provides recommendations for reassessment and management based on presume risk of the infant developing or having Early Onset Sepsis (EOS). The aim of our study was to compare these three recently published recommendations from the COFN for the management of asymptomatic neonates born to afebrile mothers with inadequate IAP for GBS.

STUDY DESIGN

This is a retrospective study of asymptomatic neonates with gestational age ≥35 weeks born to afebrile mothers with indicated inadequate IAP for GBS between April 2017 and July 2020. Management recommendations of the SRC were compared to the recommendations of categorical risk assessment and risk assessment based on clinical condition.

RESULTS

A total of 7,396 infants were born during the study period, 394 (5.3%. to mothers with inadequate IAP. Recommendations for these infants according to both the categorical risk factor guideline and the clinical condition guideline include extended, close observation. However, the SRC recommended routine newborn care for 99.7%.f these infants. None of the infants developed EOS.

CONCLUSION

The SRC recommend routine neonatal care without enhanced and prolonged observation for nearly all asymptomatic infants born to afebrile mothers with inadequate IAP. As none of the infants in this cohort had EOS, further studies in a larger cohort are needed to establish the safety of SRC in neonates born to mothers with inadequate IAP.

Asymptomatic full-term infants born to women with chorioamnionitis may not need routine antibiotics

AIM

While infants with early-onset sepsis require antibiotics, there is little evidence to support their routine use in asymptomatic infants exposed to maternal chorioamnionitis. We aimed to ascertain the incidence of culture-proven sepsis in full-term infants exposed to chorioamnionitis and to determine whether asymptomatic infants need routine antibiotic treatment.

METHODS

This study was retrospective. Included were all full-term infants admitted to our neonatal intensive care unit between 1 January 2017 and 31 May 2018 who were given intravenous antibiotics for maternal chorioamnionitis. After identifying eligible infants, relevant maternal and infant data were collected from our medical records and the Neonatal Intensive Care Units Database.

RESULTS

We selected 167 term infants from 7736 deliveries. The incidence of chorioamnionitis was 21 per 1000 deliveries. The mean gestational age was 39 weeks (range 37-41), and 57% infants were male. Asymptomatic infants (76%) received intravenous antibiotics for an average of 2 days compared to 4 days in the symptomatic group (24%), p < 0.001. No infant died or developed culture-positive sepsis.

CONCLUSION

The risk of early-onset sepsis in well-appearing term infants of mothers with chorioamnionitis is low. Further studies are mandatory to determine whether asymptomatic infants of mothers with clinical chorioamnionitis need antibiotic treatment.

Early-onset sepsis: a cohort study comparing serial clinical observation with laboratory testing

OBJECTIVE

Early onset sepsis (EOS) remains a serious and potentially fatal illness. We aimed to demonstrate that serial clinical observation (SCO) is a feasible strategy associated with fewer laboratory evaluations and unnecessary antibiotic use.

STUDY DESIGN

We compared the admissions and antibiotic therapy in neonates ≥35 weeks' gestation at risk for EOS in a prospective cohort after the implementation of a new protocol based on SCO (n = 381) with a historical cohort which received laboratory testing (n = 417).

RESULTS

There was a significant reduction in admissions for suspected sepsis (7.2% vs 2.9%, p = 0.006) and the use of antibiotics (6.1% vs 0.7%, p = 0.000) in the cohort based on SCO. There was no delay in diagnosis.

CONCLUSIONS

SCO in neonates ≥35 weeks' gestation at risk for EOS, including chorioamnionitis-exposed infants, is a feasible measure that reduces laboratory evaluations and the overuse of antibiotics respecting the bonding mother-infant.

Initiative to Reduce Antibiotic Exposure of Asymptomatic Infants Born to Mothers with Intraamniotic Infection

Infants born to mothers with intraamniotic infection (IAI) received antibiotic treatment per the Centers for Disease Control and Prevention and American Academy of Pediatrics guidelines in our neonatal intensive care unit (NICU) for early-onset bacterial sepsis evaluation. We conducted a quality improvement project to decrease antibiotic use and NICU admission in infants born to mothers with IAI.

Differential impact of abnormal vaginal colonization on perinatal outcome and association with early-onset neonatal sepsis: preterm labor vs. preterm premature rupture of membrane

OBJECTIVE

The purpose of this study was to check whether the impact of abnormal vaginal colonization on perinatal outcomes would be different in patients with preterm labor (PTL) and premature membrane rupture (PPROM). We also sought to determine the concordance rate of microorganisms isolated from the maternal vagina and neonatal blood in cases of early-onset neonatal sepsis (EONS) in PTL and PPROM.

METHODS

This retrospective study included 996 singleton pregnancies who were admitted to the high risk care unit of our institution due to PTL (n = 519) or PPROM (n = 477) and underwent vaginal culture examination at admission between January 2005 and April 2019. Abnormal vaginal colonization was defined upon isolation of aerobic microorganisms. The maternal baseline characteristics, delivery, and neonatal outcomes were compared according to the presence or absence of abnormal vaginal flora, both in PTL and PPROM.

RESULTS

The rate of abnormal vaginal colonization in PTL and PPROM was 17.0 and 21.4%, respectively. Both in PTL and PPROM, the gestational age at admission was lower in the abnormal vaginal colonization group (PTL, 27.2 ± 3.5 vs. 28.2 ± 3.5 weeks, p = .024; PPROM, 26.1 ± 5.3 vs. 27.5 ± 4.5 weeks, p = .007). Multivariable analysis demonstrated that the group with abnormal bacteria in PPROM but not in PTL had a significantly higher rate of EONS than the group without abnormal bacteria after adjustment for confounders including gestational age at admission (PPROM, odds ratio, OR [95% confidence interval, CI]: 4.172 [1.426-12.206]; PTL, OR [95% CI]: 0.661 [0.079-5.505]). Concordance analysis showed that the maternal vaginal bacteria colonization by Escherichia coli (5.9 vs. 0.5%, p = .033) and Staphylococcus aureus (14.3 vs. 0.2%, p = .032) in PPROM was significantly correlated with the microorganisms from the neonatal blood culture EONS cases. In PTL, no specific microorganisms showed concordance between maternal vaginal bacteria and microorganisms causing EONS.

CONCLUSION

Our data showed that maternal vaginal colonization in PPROM, but not in PTL, is an independent risk factor for EONS.

Ensuring a Locally Tailored Response to Early Onset Sepsis Screening Meets or Exceeds the Performance of Published Approaches

BACKGROUND

Evaluation of well-appearing neonates for early-onset sepsis (EOS) remains controversial. Multiple risk stratification approaches are currently used for the evaluation of EOS. Our aim was to quantify and compare frequency of laboratory evaluation and empirical antibiotics between published and local EOS approaches.

METHODS

This retrospective cohort study included 8240 infants born ≥35 + 0/7 weeks' gestation at an institution from October 1, 2014, to March 1, 2018. Excluded from analysis were 156 patients who exhibited either major congenital anomalies or required antibiotics for surgical issues. A total of 1680 patient charts with risk factors for EOS were reviewed for further demographic data, clinical presentation, laboratory results, and probable recommendations from 4 EOS risk assessment approaches.

RESULTS

Laboratory evaluation recommendation was 7.1% for Centers for Disease Control and Prevention 2010 guidelines and local 2016 EOS algorithm, 6% for local 2019 EOS algorithm, and 5.9% for Kaiser Permanente neonatal EOS calculator (neonatal EOS calculator). Antibiotic recommendation was 6% for 2010 Centers for Disease Control and Prevention guidelines, 4.3% for neonatal EOS calculator, and 3.3% for local 2016 and 2019 EOS algorithms.

CONCLUSIONS

Of the 4 approaches reviewed, the local 2019 EOS algorithm and the neonatal EOS calculator were similar in recommending the lowest frequency of laboratory evaluation and the local 2016 and 2019 EOS algorithms had the lowest recommended antibiotic usage in this population.

The Term Newborn: Early-Onset Sepsis

The changing epidemiology of early-onset neonatal sepsis among term infants has required reappraisal of approaches to management of newborn infants at potential risk. As this is now a rare disease, new strategies for reduction in diagnostic testing and empirical treatment have been developed. Adoption and refinement of these strategies should be a priority for all facilities where babies are born.

Application of Kaiser Sepsis Calculator in culture-positive infants with early onset sepsis

BACKGROUND

Kaiser Sepsis Calculator (KSC) reduces antibiotic use, testing and intravenous infiltrates but there are concerns about the missed early onset sepsis (EOS) cases. We sought to apply the KSC score for culture-positive infants retrospectively in infants born in the last 10 years in our hospital.

METHODS

In a retrospective cohort study, the comparison groups were divided into Group A (no antibiotics recommended by KSC) and Group B (antibiotics recommended).

RESULTS

Overall, 17/24 (71%) infants would have been started on antibiotics per KSC but 7/24 (29%) would not. The initial EOS risk was not significantly different between the groups (Group A vs. Group B: 0.44 vs. 0.76, P = 0.41), but the final risk score was (0.33 vs. 9.41, P < 0.001). In Group A (no antibiotics), 3/7 infants became symptomatic between 9 and 42 hours.

CONCLUSION

There may be a potential delay in starting antibiotics in infants that are asymptomatic at birth while using KSC.

Cost savings from use of a neonatal sepsis calculator in Australia: A modelled economic analysis

AIM

To estimate the change in average cost and length of stay (LOS) for the neonatal birth admission resulting from use of the neonatal early-onset sepsis (EOS) calculator compared to guideline-based management, in an Australian perinatal health-care setting.

METHODS

A decision-analytic model (decision tree) was constructed to assess admission cost and LOS with EOS calculator use compared to guideline-based management. Probabilities of clinical sepsis-related outcomes were obtained via review of published literature. Costs and average LOS were obtained from Australia's Independent Hospital Pricing Authority.

RESULTS

EOS calculator use was associated with a reduction in costs of AUD$25806 and in average LOS of 25.4 days per 1000 babies born. Sensitivity analyses demonstrated greater net benefits could be expected for services where there is a higher baseline rate of antibiotic use.

CONCLUSION

This model demonstrates a significant cost reduction for the neonatal birth admission, associated with use of the EOS calculator as compared to existing guidelines. The net benefit may be greater in Australia, where rates of empiric antibiotic use are reportedly high, compared to some European countries and the United States. Future research opportunities include prospective collection of economic data alongside the introduction of the EOS calculator.

Neonatal Sepsis: The Impact of Carbapenem-Resistant and Hypervirulent Klebsiella pneumoniae

The convergence of a vulnerable population and a notorious pathogen is devastating, as seen in the case of sepsis occurring during the first 28 days of life (neonatal period). Sepsis leads to mortality, particularly in low-income countries (LICs) and lower-middle-income countries (LMICs). Klebsiella pneumoniae, an opportunistic pathogen is a leading cause of neonatal sepsis. The success of K. pneumoniae as a pathogen can be attributed to its multidrug-resistance and hypervirulent-pathotype. Though the WHO still recommends ampicillin and gentamicin for the treatment of neonatal sepsis, K. pneumoniae is rapidly becoming untreatable in this susceptible population. With escalating rates of cephalosporin use in health-care settings, the increasing dependency on carbapenems, a "last resort antibiotic," has led to the emergence of carbapenem-resistant K. pneumoniae (CRKP). CRKP is reported from around the world causing outbreaks of neonatal infections. Carbapenem resistance in CRKP is largely mediated by highly transmissible plasmid-encoded carbapenemase enzymes, including KPC, NDM, and OXA-48-like enzymes. Further, the emergence of a more invasive and highly pathogenic hypervirulent K. pneumoniae (hvKP) pathotype in the clinical context poses an additional challenge to the clinicians. The deadly package of resistance and virulence has already limited therapeutic options in neonates with a compromised defense system. Although there are reports of CRKP infections, a review on neonatal sepsis due to CRKP/ hvKP is scarce. Here, we discuss the current understanding of neonatal sepsis with a focus on the global impact of the CRKP, provide a perspective regarding the possible acquisition and transmission of the CRKP and/or hvKP in neonates, and present strategies to effectively identify and combat these organisms.

Can we back off using antibiotics in the NICU?

Antibiotics are extensively and inconsistently prescribed in neonatal ICUs, and usage does not correlate with rates of culture positive sepsis. There is mounting data describing the short and long-term adverse effects associated with antibiotic overuse in neonates, including the increased burden of multi-drug resistant organisms. Currently there is considerable variation in antibiotic prescribing practice among neonatologists. Applying the practice of antibiotic stewardship in the NICU is crucial for standardizing antibiotic use and improving outcomes in this population. Several approaches have been proposed to identify neonatal sepsis, with the hope of reducing antibiotic utilization. These strategies all have their limitations, and often include laboratory testing and treatment of well-appearing, non-septic, infants. A conservative "watch and wait" algorithm is suggested as an alternative method for when to initiate antibiotics. This observational approach relies on availability of trained personnel able to examine infants at specified intervals, without delaying antibiotics, should signs of sepsis arise.

Differential impact of antiretroviral therapy initiated before or during pregnancy on placenta pathology in HIV-positive women

OBJECTIVE

To examine the association between timing of antiretroviral treatment (ART) initiation in HIV-infected women and placental histopathology.

DESIGN

A nested substudy in a larger cohort of HIV-infected women which examined the association between ART status and birth outcomes.

METHODS

Placentas (n = 130) were examined for histopathology from two ART groups: stable (n = 53), who initiated ART before conception and initiating (n = 77), who started ART during pregnancy [median (interquartile range) 15 weeks gestation (11-18)]. Using binomial regression we quantified associations between ART initiation timing with placental histopathology and pregnancy outcomes.

RESULTS

One-third of all placentas were less than 10th percentile weight-for-gestation and there was no significant difference between ART groups. Placental diameter, thickness, cord insertion position and foetal-placental weight ratio were also similar by group. However, placentas from the stable group showed increased maternal vascular malperfusion (MVM) (39.6 vs. 19.4%), and decreased weight (392 vs. 422 g, P = 0.09). MVM risk was twice as high [risk ratios 2.03 (95% confidence interval: 1.16-3.57); P = 0.01] in the stable group; the increased risk remaining significant when adjusting for maternal age [risk ratios 2.04 (95% confidence interval: 1.12-3.72); P = 0.02]. Furthermore, MVM was significantly associated with preterm delivery and low birth weight (P = 0.002 and <0.0001, respectively).

CONCLUSION

Preconception initiation of ART was associated with an increased MVM risk, and may contribute to placental dysfunction. The association between MVM with preterm delivery and low birth weight suggests that a placenta-mediated mechanism likely links the putative association between long-term use of ART and adverse birth outcomes.

Early-Onset Sepsis in Neonates - A Population-Based Study in South-West Norway From 1996 to 2018

Background: The epidemiology of early-onset sepsis (EOS) may change over time. Longitudinal surveillance of causative pathogens, antibiotic susceptibility patterns and antibiotic therapy is important for optimal therapy strategies. Objectives: To describe the incidence of culture-confirmed EOS, causative pathogens, antibiotic susceptibility patterns and antibiotic therapy over a 23-year period. Methods: Retrospective population-based study from a single-center neonatal intensive care unit at Stavanger University Hospital, Norway, covering a population in South-West Norway, during the 23-year period 1996-2018. Results: Of 104,377 live born infants, 101 infants (0.97/1,000) had culture-confirmed EOS; 89 with Gram positive and 12 with Gram-negative bacteria. The EOS-attributable mortality was 6/101 (5.8%). For the three most prevalent pathogens the incidences were; Group B streptococcus (GBS) 0.57/1,000, Escherichia coli 0.11/1,000 and viridans group streptococci (VGS) 0.10/1,000. GBS was the most common pathogen (59/93; 63%) in infants with gestational age (GA) ≥ 28 weeks. In contrast, among extremely preterm infants (GA <28 weeks) the incidence of E. coli infection was higher than for GBS infection. The second most common bacterial pathogens causing EOS among term infants were VGS. There was no change in the incidence of EOS for the entire study period, but from 2000 to 2018 there was a mean decline in EOS by 6% per year (95% CI 1%-10%) (p = 0.019). The incidences of GBS and E. coli did not change during the study period. The initial empirical antibiotic regimen for EOS was in all cases a combination of benzylpenicillin or ampicillin and an aminoglycoside, but in 21/101 (21%) of cases a broad-spectrum antibiotic was either added or substituted this regimen. In 2/101 (2%) EOS cases, the pathogens were nonsusceptible to the empirical antibiotic regimen. All E. coli isolates were susceptible to aminoglycosides. Conclusion: GBS was the most common causative pathogens in EOS, but E. coli dominated in infants with GA <28 weeks. There was no change in the incidence of EOS during the entire study period. The current empiric regimen with benzylpenicillin and gentamicin provides a very high coverage for EOS in our setting.

Management of infants born to mothers with chorioamnionitis: A retrospective comparison of the three approaches recommended by the committee on fetus and newborn

BACKGROUND

Based on the most recently published recommendations from the Committee on the Fetus and Newborn (COFN), three approaches currently exist for the use of risk factors to identify infants who are at increased risk of early-onset sepsis (EOS). Categorical risk factor assessments recommend laboratory testing and empiric antibiotic therapy for all infants born to mothers with a clinical diagnosis of chorioamnionitis. Risk assessments based on clinical condition recommend frequent examinations and close vital sign monitoring for infants born to mothers with chorioamnionitis. The Kaiser Permanente EOS risk calculator (SRC) is an example of the third approach, multivariate risk assessments. The aim of our study was to compare the three risk stratification approaches recommended by the COFN for management of chorioamnionitis-exposed infants.

METHODS

Retrospective study of 1,521 infants born ≥35 weeks to mothers with chorioamnionitis. Management recommendations of the SRC were compared to the recommendations of categorical risk assessment and risk assessment based on clinical condition (CCA).

RESULTS

Hypothetical application of SRC and CCA resulted in 79.6% and 76.8-85.1% respectively fewer infants allocated empiric antibiotic therapy. While CCA recommended enhanced observation for all chorioamnionitis-exposed infants, SRC recommended routine care without enhanced observation in 44.3% infants. For the six infants (0.39%) with EOS, SRC and CCA recommended empiric antibiotics only for three symptomatic infants.

CONCLUSION

The SRC and CCA can reduce antibiotic use but potentially delay antibiotic treatment. The SRC does not recommend enhanced observation with frequent and prolonged vital signs for >44% of chorioamnionitis-exposed infants.

Amniotic fluid Gram stain and interleukin-6 can predict early-onset neonatal sepsis

AIM

To clarify whether amniotic fluid findings (Gram stain and interleukin [IL]-6 level) can predict early-onset neonatal sepsis (EONS) before delivery.

METHODS

We compared the sensitivity and specificity and the values of the area under the receiver-operating characteristic (AUROC) curve of maternal inflammatory responses and amniotic fluid findings using IL-6 and Gram stain to predict EONS. Patients who underwent amniocentesis for suspected intra-amniotic infection (IAI) after 22 weeks and 0 days of gestation and delivered on the same day at our hospital between January 2013 and December 2018 were included.

RESULTS

Out of 200 patients, EONS developed in 9 patients. The AUROC curves of maternal white blood cells count, C-reactive protein and body temperature were low (range, 0.6-0.7), whereas that of amniotic fluid IL-6 was high (0.90). Sensitivity and specificity for amniotic fluid findings were, respectively, 100% and 67% for IL-6 (cut-off value: 17.4 ng/mL) and 100% and 88% for the Gram stain; these values were superior to those of maternal inflammatory responses. When examining the accuracy of the amniotic fluid Gram stain separately before and after 34 gestation weeks, similar results were obtained. Amniotic fluid IL-6 before 34 gestation weeks showed specificity similar to that of the Gram stain; however, there were large differences in cut-off values based on gestational age.

CONCLUSION

Gram stain results of amniotic fluid can predict EONS with high sensitivity and specificity when IAI is suspected. False-negative amniotic fluid Gram stain results can be prevented by measuring amniotic fluid IL-6 simultaneously.

Association of early life antibiotics and health outcomes: Evidence from clinical studies

Preterm infants are susceptible to infections that can rapidly progress to disastrous outcomes. Antibiotics are lifesaving, but their prolonged and inappropriate use are associated with adverse outcomes. In this review, we discuss the current status of antimicrobial use in the preterm neonatal population, and the challenges in determining the initiation, duration, and choice of antibiotics. Finally, we review the clinical studies on the potential consequences of prolonged antimicrobial exposure in prematurely born infants.