Noninfectious influencers of early-onset sepsis biomarkers

The potential role of heparin-binding protein in neonatal sepsis: research progress

Neonatal sepsis is a major global health challenge, leading to significant morbidity and mortality in newborns. The search for precise biomarkers for its early prediction in clinical settings has been ongoing, with heparin-binding protein (HBP) emerging as a promising candidate. Originating from granules in neutrophils, HBP is released into the bloodstream in response to infection and plays a pivotal role in the body's inflammatory response. Its significance extends beyond its inflammatory origins; research indicates dynamic changes in HBP levels are strongly linked to reduce in-hospital mortality, offering a prognostic advantage over existing biomarkers. Furthermore, HBP has demonstrated considerable clinical utility in the early diagnosis and stratification of neonatal sepsis, suggesting its potential as a reliable blood marker for early prediction of the disease and its severity. Its application may extend to guiding the judicious use of antibiotics in treating newborns, addressing a critical aspect of neonatal care. Despite these encouraging results, the precise clinical utility of HBP for diagnosing and treating sepsis in neonates still demands further clarification through extensive research. This review delves into the current scientific understanding of HBP's contribution to diagnosing, prognosticating, and treating neonatal sepsis, while considering its future clinical applications.

Use and utility of C-reactive protein (CRP) in neonatal early-onset sepsis: a secondary analysis of a prospective surveillance study

OBJECTIVE

Characterize C-reactive protein (CRP) within 72 postnatal hours in early-onset sepsis (EOS).

STUDY DESIGN

Secondary analysis of a prospective surveillance study of neonates with EOS 2015-2017. We examined CRP use by center and neonatal characteristics, and CRP levels by time, neonatal characteristics, clinical signs, and pathogen.

RESULTS

CRP was obtained for 96/235 neonates with EOS, which varied by center (p < 0.001). 71/95 had CRP > 10 mg/L (1 missing). Neonatal characteristics with and without CRP did not differ. There was no relationship between CRP level and timing (p = 0.41) or neonate characteristics. Median CRP was higher with ≥5 vs <5 clinical signs (56, 23 mg/L; p = 0.002), and was not different in Gram-positive vs Gram-negative sepsis (43, 51 mg/L; p = 0.37) or preterm neonates who died vs survived (38, 28 mg/L; p = 0.37).

CONCLUSIONS

Among neonates with EOS, CRP use varied by center. CRP levels did not differ by time, neonate characteristics, pathogen, or death.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov ID Early-Onset Sepsis an NICHD/CDC Surveillance Study (EOSII): NCT02410486.

Neonatal bacterial sepsis

Neonatal sepsis remains one of the key challenges of neonatal medicine, and together with preterm birth, causes almost 50% of all deaths globally for children younger than 5 years. Compared with advances achieved for other serious neonatal and early childhood conditions globally, progress in reducing neonatal sepsis has been much slower, especially in low-resource settings that have the highest burden of neonatal sepsis morbidity and mortality. By contrast to sepsis in older patients, there is no universally accepted neonatal sepsis definition. This poses substantial challenges in clinical practice, research, and health-care management, and has direct practical implications, such as diagnostic inconsistency, heterogeneous data collection and surveillance, and inappropriate treatment, health-resource allocation, and education. As the clinical manifestation of neonatal sepsis is frequently non-specific and the current diagnostic standard blood culture has performance limitations, new improved diagnostic techniques are required to guide appropriate and warranted antimicrobial treatment. Although antimicrobial therapy and supportive care continue as principal components of neonatal sepsis therapy, refining basic neonatal care to prevent sepsis through education and quality improvement initiatives remains paramount.

Diagnostic value of maternal, cord blood and neonatal biomarkers for early-onset sepsis: a systematic review and meta-analysis

BACKGROUND

An accurate diagnosis of early-onset sepsis (EOS) is challenging because of subtle symptoms and the lack of a good diagnostic tool, resulting in considerable antibiotic overtreatment. A biomarker, discriminating between infected and non-infected newborns at an early stage of the disease, could improve EOS prediction. Numerous biomarkers have been tested, but have never been compared directly.

OBJECTIVES

We aimed to provide a comprehensive overview of early biomarkers and their diagnostic value in maternal samples, umbilical cord blood, and neonatal serum.

DATA SOURCES

PubMed-Medline, EMBASE, The Cochrane Library, and Web of Science were searched up to 1 March 2023, without restrictions on publication date, population, or language.

STUDY ELIGIBILITY CRITERIA

Articles describing the diagnostic value of at least one biomarker in the detection of EOS in neonates, independent of gestational age, were included.

ASSESSMENT OF RISK OF BIAS

The QUADAS-2 tool was used to assess study quality.

METHODS OF DATA SYNTHESIS

Three independent researchers assessed the articles using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Meta-analysis was performed with all manuscripts describing diagnostic accuracy using a random-effects model.

RESULTS

Of 2296 identified articles, 171 reports were included in the systematic review and 69 in the meta-analysis. Literature showed mixed and inconsistent evidence for most biomarkers and sample types, because of a lack of a uniform EOS case definition, small sample sizes, and large heterogeneity between studies. Interesting markers were procalcitonin (pooled sensitivity 79%, 95% CI 71-84%; specificity 91%, 95% CI 83-96%, n = 11) and interleukin (IL)-6 (pooled sensitivity 83%, 95% CI 71-90%; specificity 87%, 95% CI 78-93%, n = 8) in umbilical cord blood and presepsin (pooled sensitivity 82%, 95% CI 62-93%; specificity 86%, 95% CI 73-93%, n = 3) and serum amyloid A (pooled sensitivity 92%, 95% CI 75-98%; specificity 96%, 95% CI 78-99%, n = 4) in neonatal serum. Studies on the combination of biomarkers were scarce.

CONCLUSIONS

A biomarker stand-alone test is currently not reliable for direct antibiotic stewardship in newborns, although several biomarkers show promising initial results. Further research into biomarker combinations could lead to an improved EOS diagnosis, reduce antibiotic overtreatment, and prevent associated health-related problems.

Antibiotic Stewardship in the Neonatal Intensive Care Unit

Antibiotic stewardship is a multidisciplinary, evidence-based approach to optimize antibiotic use and mitigate development of antibiotic resistance. Neonates have high rates of antibiotic exposure, particularly those born preterm and admitted to the NICU, and mounting evidence describes the adverse consequences of such exposures in the absence of infection. Here, we review the general principles of antibiotic stewardship and how they can be applied in NICUs. The unique characteristics of NICUs and patients cared for in this setting, which warrant unique implementation strategies and special considerations are discussed. We summarize current antibiotic use metrics for assessment of responses to stewardship interventions and changes over time, and review evidence-based infection prevention practices in the NICU. Current recommendations for empiric antibiotic use in the NICU and the utility of infection biomarkers are summarized. Lastly, given the growing global threat of increasing antibiotic resistance, specific threats in the NICU are highlighted.

Hypoxic-ischaemic encephalopathy based on clinical signs and symptoms and associated factors among neonates, Southern Ethiopian public hospitals: a case-control study

Background

Hypoxic-ischaemic encephalopathy (HIE) is a severe condition that results from reduced oxygen supply and blood flow to the brain, leading to brain injury and potential long-term neurodevelopmental impairments. This study aimed to identify the maternal and neonatal factors associated with hypoxic-ischaemic encephalopathy among Neonates.

Methods

The authors conducted a case-control study in 15 public hospitals with 515 neonates and mothers (175 cases and 340 controls). The authors used a questionnaire and clinical records created and managed by Kobo software to collect data. The authors diagnosed hypoxic-ischaemic encephalopathy (HIE) by clinical signs and symptoms. The authors used logistic regression to identify HIE factors.

Results

Hypoxic-ischaemic encephalopathy (HIE) was associated with maternal education, ultrasound checkup, gestational age, delivery mode, and labour duration. Illiterate mothers [adjusted odds ratio (AOR)= 1.913, 95% CI: 1.177, 3.109], no ultrasound checkup (AOR= 1.859, 95% CI: 1.073, 3.221), preterm (AOR= 4.467, 95% CI: 1.993, 10.012) or post-term birth (AOR= 2.903, 95% CI: 1.325, 2.903), caesarean section (AOR= 7.569, 95% CI: 4.169, 13.741), and prolonged labour (AOR= 3.591, 95% CI: 2.067, 6.238) increased the incidence of HIE.

Conclusion

This study reveals the factors for hypoxic-ischaemic encephalopathy among neonates in Ethiopia. The authors found that neonates born to illiterate women, those who experienced prolonged labour, those whose mothers did not have ultrasound checkups during pregnancy, those delivered by caesarean section, and those born preterm, or post-term were more likely to develop hypoxic-ischaemic encephalopathy. These findings indicate that enhancing maternal education and healthcare services during pregnancy and delivery may positively reduce hypoxic-ischaemic encephalopathy among neonates.

Game changer or gimmick: inflammatory markers to guide antibiotic treatment decisions in neonatal early-onset sepsis

BACKGROUND

The diagnosis of neonatal early-onset sepsis (EOS) is challenging, and inflammatory markers are widely used to guide decision-making and therapies.

OBJECTIVES

This narrative review presents the current state of knowledge regarding the diagnostic value and potential pitfalls in the interpretation of inflammatory markers for EOS.

SOURCES

PubMed until October 2022 and searched references in identified articles using the search terms: neonatal EOS, biomarker or inflammatory marker, and antibiotic therapy or antibiotic stewardship.

CONTENT

In situations with a high or low probability of sepsis, the measurements of inflammatory markers have no impact on the decision to start or stop antibiotics and are just gimmick, whereas they may be a game changer for neonates with intermediate risk and therefore an unclear situation. There is no single or combination of inflammatory markers that can predict EOS with high probability, allowing us to make decisions regarding the start of antibiotics based only on inflammatory markers. The main reason for the limited accuracy is most probably the numerous noninfectious conditions that influence the levels of inflammatory markers. However, there is evidence that C-reactive protein and procalcitonin have good negative predictive accuracy to rule out sepsis within 24 to 48 hours. Nevertheless, several publications have reported more investigations and prolonged antibiotic treatments with the use of inflammatory markers. Given the limitations of current strategies, using an algorithm with only moderate diagnostic accuracy may have a positive impact, as reported for the EOS calculator and the NeoPInS algorithm.

IMPLICATIONS

As the decision regarding the start of antibiotic therapy is different from the process of stopping antibiotics, the accuracy of inflammatory markers needs to be evaluated separately. Novel machine learning-based algorithms are required to improve accuracy in the diagnosis of EOS. In the future, inflammatory markers included in algorithms may be a game changer reducing bias and noise in the decision-making process.

Fetal and neonatal alloimmune thrombocytopenia: No evidence of systemic inflammation as a modulator of disease severity. Could placental inflammation be key?

In fetal/neonatal alloimmune thrombocytopenia (FNAIT), maternal alloantibodies against paternal human platelet antigens (HPA) cross the placenta and lead to platelet destruction. The extent of thrombocytopenia varies among neonates, and inflammation may constitute an important trigger. A set of stable inflammatory markers was measured in serum samples from neonates with low platelet counts, of which n = 50 were diagnosed with FNAIT due to anti-HPA-1a antibodies and n = 50 were thrombocytopenic without detectable maternal HPA antibodies. Concentrations of C-reactive protein, soluble CD14, procalcitonin, and sFlt-1 did not differ between the two cohorts. There was no correlation between C-reactive protein or soluble CD14 and the platelet count, but a negative correlation between procalcitonin concentrations and the neonatal platelet count in both cohorts. sFlt-1 concentration and the platelet count were correlated in FNAIT cases exclusively. None of the inflammatory markers was statistically different between cases with and without intracranial haemorrhage. We were unable to identify systemic inflammation as a relevant factor for thrombocytopenia in FNAIT. The antiangiogenic enzyme sFlt-1, released by the placenta, did correlate with the platelet count in FNAIT cases. Our findings may give rise to the hypothesis that placental inflammation rather than systemic inflammation modulates disease severity in FNAIT.

New strategies to Reduce Unnecessary Antibiotic Use in the NICU: A Quality Improvement Initiative

Introduction

Early-onset sepsis (EOS) and late-onset Sepsis (LOS) are common diagnoses entertained in sick newborns treated in neonatal intensive care units (NICUs), and antibiotics are the medications most prescribed in NICUs. Antibiotic stewardship programs have an important impact on limiting unnecessary antibiotic use.

Methods

Following the Model for Improvement, between 2/1/16 and 1/31/17, at a level 3 NICU, a multidisciplinary team implemented PDSA cycles to promote antibiotic stewardship practices for newborns at risk of EOS and LOS. The main goal was to decrease the antibiotic usage rate (AUR) safely. Primary strategies included discontinuing antibiotics within 24 hours of life if the newborn was stable, and the blood culture was negative for EOS and implementing an "antibiotic time-out" during rounds.

Results

For all newborns admitted to our NICU, the AUR decreased, for EOS from 137 to 32 days per 1000 patient days (77% reduction) and for LOS from 277 to 121 days per 1000 patient days (56% reduction). We demonstrated the sustainability of both EOS-AUR and LOS-AUR during the 2 years postcompletion of the intervention period. There were no adverse effects of reducing the AUR.

Conclusion

Interventions that reduce unnecessary antibiotic use in the NICU are safe and prevent excessive antibiotic exposure.

Diagnostic Performance and Patient Outcomes With C-Reactive Protein Use in Early-Onset Sepsis Evaluations

OBJECTIVES

To determine performance of C-reactive protein (CRP) in the diagnosis of early-onset sepsis, and to assess patient outcomes with and without routine use of CRP.

STUDY DESIGN

This was a retrospective cohort study of infants admitted to 2 neonatal intensive care units. CRP was used routinely in early-onset sepsis evaluations during 2009-2014; this period was used to determine CRP performance at a cut-off of ≥10 mg/L in diagnosis of culture-confirmed early-onset sepsis. Routine CRP use was discontinued during 2018-2020; outcomes among infants admitted during this period were compared with those in 2012-2014.

RESULTS

From 2009 to 2014, 10 134 infants were admitted; 9103 (89.8%) had CRP and 7549 (74.5%) had blood culture obtained within 3 days of birth. CRP obtained ±4 hours from blood culture had a sensitivity of 41.7%, specificity 89.9%, and positive likelihood ratio 4.12 in diagnosis of early-onset sepsis. When obtained 24-72 hours after blood culture, sensitivity of CRP increased (89.5%), but specificity (55.7%) and positive likelihood ratio (2.02) decreased. Comparing the periods with (n = 4977) and without (n = 5135) routine use of CRP, we observed lower rates of early-onset sepsis evaluation (74.5% vs 50.5%), antibiotic initiation (65.0% vs 50.8%), and antibiotic prolongation in the absence of early-onset sepsis (17.3% vs 7.2%) in the later period. Rate and timing of early-onset sepsis detection, transfer to a greater level of care, and in-hospital mortality were not different between periods.

CONCLUSIONS

CRP diagnostic performance was not sufficient to guide decision-making in early-onset sepsis. Discontinuation of routine CRP use was not associated with differences in patient outcomes despite lower rates of antibiotic administration.

Group B Streptococcus Early-Onset Disease: New Preventive and Diagnostic Tools to Decrease the Burden of Antibiotic Use

The difficulty in recognizing early-onset neonatal sepsis (EONS) in a timely manner due to non-specific symptoms and the limitations of diagnostic tests, combined with the risk of serious consequences if EONS is not treated in a timely manner, has resulted in a low threshold for starting empirical antibiotic treatment. New guideline strategies, such as the neonatal sepsis calculator, have been proven to reduce the antibiotic burden related to EONS, but lack sensitivity for detecting EONS. In this review, the potential of novel, targeted preventive and diagnostic methods for EONS is discussed from three different perspectives: maternal, umbilical cord and newborn perspectives. Promising strategies from the maternal perspective include Group B Streptococcus (GBS) prevention, exploring the virulence factors of GBS, maternal immunization and antepartum biomarkers. The diagnostic methods obtained from the umbilical cord are preliminary but promising. Finally, promising fields from the newborn perspective include biomarkers, new microbiological techniques and clinical prediction and monitoring strategies. Consensus on the definition of EONS and the standardization of research on novel diagnostic biomarkers are crucial for future implementation and to reduce current antibiotic overexposure in newborns.

Neonatal Early-Onset Sepsis

Early-onset sepsis (EOS) is a significant cause of morbidity and mortality among newborn infants, particularly among those born premature. The epidemiology of EOS is changing over time. Here, we highlight the most contemporary data informing the epidemiology of neonatal EOS, including incidence, microbiology, risk factors, and associated outcomes, with a focus on infants born in high-income countries during their birth hospitalization. We discuss approaches to risk assessment for EOS, summarizing national guidelines and comparing key differences between approaches for term and preterm infants. Lastly, we analyze contemporary antibiotic resistance data for EOS pathogens to inform optimal empiric treatment for EOS.

Effect of Therapeutic Hypothermia Treatment on Acute Phase Reactants

Objective In our study, we aimed to examine the effect of therapeutic hypothermia treatment on C-reactive protein (CRP) and interleukin-6 (IL-6) in infants with hypoxic ischemic encephalopathy (HIE).

Methods The data of the patients with the diagnosis of HIE we followed up in our unit between 2017 and 2018 were analyzed retrospectively. Patients who died during follow-up and patients with proven septicemia at the time of examination were excluded from the study. The routine CRP and IL-6 values ​​of the patients included in the study were compared before and after hypothermia treatment.

Results Therapeutic hypothermia treatment applied for 72 hours was found to cause a statistically significant increase in CRP after treatment when compared with the values ​​measured before treatment (0.6 (0.2–1.9) before and median (P25–75), and after treatment 7.5 (4–18) and median (P25–75) mg/L, p=0.00). While IL-6 was found to be high in the early period due to the effect of hypoxia, it was found to be low after hypothermia treatment (80.5 (40–200) median (P25–75) – 32 (18–50) median (P25–75) pg/ml, p=0.131). While the white blood cell count was high before hypothermia treatment due to hypoxia, it was found to be low after treatment (24600 (19600–30100) median (P25–75) –11300 (8800–14200) median (P25–75)/µL, p=0.001).

Conclusion White blood cells and IL-6 can be found to be high due to hypoxia without infection, and CRP can be found to be high after therapeutic hypothermia treatment without infection. The effect of hypoxia and hypothermia should be considered when evaluating acute phase reactants.

Paediatric and neonatal sepsis and inflammation

Sepsis has a huge impact on global mortality and has been declared as a priority by the World Health organisation the WHO.1 Children have a high incidence of sepsis especially in the neonatal with an estimated 3 million babies affected worldwide and mortality ranges from 11 to 19%.2 In addition, long-term neurodevelopmental outcomes are affected but this is largely unquantified. However, challenges remain in the early recognition, diagnosis and standardised management of sepsis. This series on Sepsis and inflammation in children reviews the conundrums of diagnostic criteria, biomarkers, management and future strategies to improve outcomes.