Incidence of neonatal necrotising enterocolitis in high-income countries: a systematic review

Microbiome-targeting therapies in the neonatal intensive care unit: safety and efficacy

Microbiome-targeting therapies have received great attention as approaches to prevent disease in infants born preterm, but their safety and efficacy remain uncertain. Here we summarize the existing literature, focusing on recent meta-analyses and systematic reviews that evaluate the performance of probiotics, prebiotics, and/or synbiotics in clinical trials and studies, emphasizing interventions for which the primary or secondary outcomes were prevention of necrotizing enterocolitis, late-onset sepsis, feeding intolerance, and/or reduction in hospitalization length or all-cause mortality. Current evidence suggests that probiotics and prebiotics are largely safe but conclusions regarding their effectiveness in the neonatal intensive care unit have been mixed. To address this ambiguity, we evaluated publications that collectively support benefits of probiotics with moderate to high certainty evidence in a recent comprehensive network meta-analysis, highlighting limitations in these trials that make it difficult to support with confidence the routine, universal administration of probiotics to preterm infants.

Probiotics to prevent necrotizing enterocolitis in very low birth weight infants: A network meta-analysis

Objective

This study aims to review the evidence for the optimal regimen of probiotics for the prevention of necrotizing enterocolitis (NEC) in very low birth weight infants.

Design

Through searching PubMed, EMBASE, Cochrane Library, and Web of Science till September 30, 2022, only randomized controlled trials were included to evaluate the optimal regimen of probiotics for the prevention of NEC in very low birth weight infants. The methodological quality of the included studies was assessed by the Cochrane risk of bias assessment tool (RoB 2), and the collected data were analyzed accordingly using Stata software.

Results

Twenty-seven RCTs were included, and the total sample size used in the study was 529. The results of the network meta-analysis showed that Bovine lactoferrin + Lactobacillus rhamnosus GG (RR 0.03; 95% CI 0.00-0.35), Lactobacillus rhamnosus + Lactobacillus plantarum + Lactobacillus casei + Bifidobacterium lactis (RR 0.06; 95% CI 0.00-0.70), Bifidobacterium lactis + inulin (RR 0.16; 95% CI 0.03-0.91) were superior to the control group (Bifidobacterium lactis + Bifidobacterium longum) in reducing the incidence of NEC. The reduction in the incidence of NEC were as follows: Bovine lactoferrin + Lactobacillus rhamnosus GG (SUCRA 95.7%) > Lactobacillus rhamnosus + Lactobacillus plantarum + Lactobacillus casei + Bifidobacterium lactis (SUCRA 89.4%) > Bifidobacterium lactis + inulin (SUCRA 77.8%).

Conclusions

This network meta-analysis suggests that Lactobacillus rhamnosus GG combined with bovine lactoferrin maybe the most recommended regimen for the prevention of NEC in very low birth weight infants.

Oral Application of Mother's Own Milk for Reducing Necrotizing Enterocolitis in Preterm Infants: An Updated Meta-Analysis of RCTs

Background

Necrotizing enterocolitis (NEC) and late-onset sepsis (LOS) are the major contributors to mortality and morbidity in preterm infants. This updated meta-analysis was aimed to assess the effects of mother's milk on the incidence of NEC, LOS, and other clinical outcomes in preterm infants.

Methods

PubMed, Embase, and the Cochrane library were searched for papers published up to October 2022.

Results

A total of 13 RCTs with 1330 infants were included in the final analysis. Significant difference in NEC (stage 2 or 3) was found between the intervention group and the control group (RR = 0.508, 95% CI: 0.314-0.822, and P=0.008). The incidence of proven LOS (RR = 0.809, 95% CI: 0.610-1.071, and P=0.139) and death (RR = 0.800, 95% CI: 0.571-1.122, and P=0.196) was comparable between the two groups. Statistical differences in the incidence of proven or probable LOS (RR = 0.705, 95% CI: 0.577-0.862, and P=0.001) and length of hospitalization (WMD = -4.868, 95% CI: -6.608 to -3.128, and P < 0.001) between the intervention group and the control group were observed.

Conclusions

The results of this updated meta-analysis showed that compared to the placebo, mother's milk provides better effects in reducing the incidences of NEC, proven or probable LOS, and the length of stay, whereas no significant benefit of mother's milk was observed in reducing the incidence of proven LOS and death.

A quality improvement initiative to reduce necrotizing enterocolitis in high-risk neonates

OBJECTIVE

Prompted by an acute increase in necrotizing enterocolitis (NEC) rates, we aimed to decrease the rate of stage 2 or greater NEC in infants born at <1500 grams or <30 weeks gestational age from 19.5% to less than 9.7% (a 50% reduction) within 18 months, without adversely affecting central line-associated bloodstream infection (CLABSI) rates.

STUDY DESIGN

We utilized Define, Measure, Analyze, Improve, and Control (DMAIC) as our improvement model. Informed by our key driver diagram and root cause analyses, six Plan-Do-Study-Act cycles were completed.

RESULTS

147 infants in the QI initiative had a median gestational age of 28.1 weeks and a median birthweight of 1070 grams. NEC rates decreased from the QI baseline of 19.5% to 6% (p = 0.03). Oral care administration increased, and maximal gavage tube dwell time decreased.

CONCLUSION

NEC rates decreased during this QI initiative through a combination of multidisciplinary interventions aimed at reducing dysbiosis.

Factors That Influence the Sustainability of Human Milk Donation to Milk Banks: A Systematic Review

Donor human milk is the recommended alternative for feeding preterm or low birth weight infants when the mother's own milk is unavailable or not in sufficient quantity. Globally, the needs of vulnerable infants for donor human milk exceed the supply. This review aimed to identify the factors impacting the sustainability of human milk donation to milk banks. A systematic review of the literature was performed on eight databases to retrieve articles published until December 2021. The study protocol is available in PROSPERO (#CRD42021287087). Among the 6722 references identified, 10 studies (eight quantitative observational and two qualitative) met the eligibility criteria for a total of 7053 participants. Thirty factors influencing the sustainability of the donations to milk banks were identified and categorized as follows: (1) donation duration, (2) donors' infant features (e.g., gestational age, birth weight), (3) donors' features (e.g., socio-demographic characteristics, milk donation history), and (4) factors related to the milk bank and health care systems (awareness and support). The available evidence suggests that larger volumes of donated milk are associated with a longer duration of donation, as are early donation, previous milk donation, and donors with an infant of smaller weight and gestational age. Supporting and encouraging early donation and recruiting donors with infants of low birth weight and low gestational age could support longer donation times and greater volumes of milk donated. To identify efficient strategies and to draw appropriate recommendations to improve donor milk access, future studies should further explore the issues of the sustainability of human milk donation to milk banks.

Remote ischaemic pre-conditioning reduces intestinal ischaemia reperfusion injury in a newborn rat

OBJECTIVE

Remote ischaemic conditioning (RIC) has been shown to reduce ischaemia-reperfusion injury(IRI) in multiple organ systems. IRI is seen in multiple bowel pathologies in the newborn, including NEC. We investigated the potential of RIC as a novel therapy for various intestinal pathologies in the newborn.

METHODS

We used an established intestinal IRI model in rat pups which results in similar intestinal injury to necrotising enterocolitis (NEC). Animals were randomly allocated to IRI only(n = 14), IRI + RIC(n = 13) or sham laparotomy(n = 10). The macroscopic extent of intestinal injury is reported as a percentage of total small bowel. Injury severity was measured using Chiu-Park scoring. Neutrophil infiltration/activation was assayed by myeloperoxidase activity. Immunohistochemistry was used to assess the expression of hypoxia-inducible factor alpha (HIF-1α). Data are median (interquartile range).

RESULTS

Animals that underwent RIC showed a decreased extent of macroscopic injury from 100%(85-100%) in the IRI only group to 58%(15-84%, p = 0.003) in the IRI + RIC group. Microscopic injury score was significantly lower in animals that underwent RIC compared to IRI alone (3.5[1.25-5] vs 5.5[4-6], p = 0.014). Intestinal myeloperoxidase activity in animals exposed to IRI was 3.4 mU/mg of tissue (2.5-3.7) and 2.1 mU/mg(1.5-2.8) in the IRI + RIC group(p = 0.047). HIF-1α expression showed a non-significant trend towards reduced expression in the IRI + RIC group.

CONCLUSIONS

RIC reduces the extent and severity of bowel injury in this animal model, supporting the hypothesis that RIC has therapeutic potential for intestinal diseases in the newborn.

Review of Necrotizing Enterocolitis and Spontaneous Intestinal Perforation Clinical Presentation, Treatment, and Outcomes

The Necrotizing Enterocolitis Surgery Trial (NEST) highlights the importance of distinguishing necrotizing enterocolitis (NEC) from spontaneous intestinal perforation (SIP) when developing surgical treatment plans. Further research is needed to increase the accuracy of this distinction, but even with our current abilities to do this initial laparotomy appears to be optimal for infants with presumed NEC. The preferred initial operation for those with SIP is more equivocal. Rates of NEC are likely decreasing slowly, whereas those with SIP are not. New imaging modalities, especially ultrasound, are becoming more useful but require more detailed investigation. Understanding the mechanisms causing these two conditions remains of paramount importance.

The chance of spontaneous patent ductus arteriosus closure in preterm infants born before 32 weeks of gestation is high and continues to increase until 5 years of follow-up

AIM

The primary aim was to estimate premature infants' spontaneous patent ductus arteriosus closure rate. Secondly, to identify criteria associated with the chance of spontaneous closure.

METHODS

We performed a retrospective cohort study of 167 infants born before 32 weeks of gestation and diagnosed with a patent ductus arteriosus between 1 January 2008 and 31 December 2017. The spontaneous patent ductus arteriosus closure event rate was evaluated using the Kaplan-Meier estimator.

RESULTS

The spontaneous closure rate within the first year of life was 66% (95% CI 58%-73%), increasing to 80% (95% CI 72%-86%) five years after birth. When including both spontaneous closure and closure following treatment, 96% (95% CI 86%-100%) closed within 5 years after birth. The chance of spontaneous closure was reduced in the case of a large patent ductus arteriosus: OR 0.16 (95% CI 0.05-0.52), left atrial enlargement: OR 0.16 (95% CI 0.05-0.51), and pulmonary hypertension: OR 0.23 (95% CI 0.07-0.74).

CONCLUSION

The chance of spontaneous closure in premature infants born between 23 and 32 weeks of gestation was high, and the incidence continued increasing until 5 years of follow-up.

Mechanisms affecting the gut of preterm infants in enteral feeding trials: a nested cohort within a randomised controlled trial of lactoferrin

OBJECTIVE

To determine the impact of supplemental bovine lactoferrin on the gut microbiome and metabolome of preterm infants.

DESIGN

Cohort study nested within a randomised controlled trial (RCT). Infants across different trial arms were matched on several clinical variables. Bacteria and metabolite compositions of longitudinal stool and urine samples were analysed to investigate the impact of lactoferrin supplementation.

SETTING

Thirteen UK hospitals participating in a RCT of lactoferrin.

PATIENTS

479 infants born <32 weeks' gestation between June 2016 and September 2017.

RESULTS

10 990 stool and 22 341 urine samples were collected. Analyses of gut microbiome (1304 stools, 201 infants), metabolites (171 stools, 83 infants; 225 urines, 90 infants) and volatile organic compounds (314 stools, 117 infants) were performed. Gut microbiome Shannon diversity at 34 weeks corrected age was not significantly different between infants in the lactoferrin (mean=1.24) or placebo (mean=1.06) groups (p=0.11). Lactoferrin receipt explained less than 1% variance in microbiome compositions between groups. Metabolomic analysis identified six discriminative features between trial groups. Hospital site (16%) and postnatal age (6%) explained the greatest variation in microbiome composition.

CONCLUSIONS

This multiomic study identified minimal impacts of lactoferrin but much larger impacts of hospital site and postnatal age. This may be due to the specific lactoferrin product used, but more likely supports the findings of the RCT in which this study was nested, which showed no impact of lactoferrin on reducing rates of sepsis. Multisite mechanistic studies nested within RCTs are feasible and help inform trial interpretation and future trial design.

Early antibiotic use and incidence of necrotising enterocolitis in very preterm infants: a protocol for a UK based observational study using routinely recorded data

INTRODUCTION

Necrotising enterocolitis (NEC) remains a major contributor to preterm mortality and morbidity. Prolonged duration of antibiotic therapy after delivery is associated with later NEC development but recent evidence suggests that absence of antibiotic treatment after delivery may also increase NEC risk. We will explore this controversy using a large pre-existing dataset of preterm infants in the UK.

METHODS AND ANALYSIS

This is a retrospective cohort study using data from UK National Neonatal Research Database (NNRD) for infants born 1 January 2012 to 31 December 2020. Eligible infants will be <32 weeks gestation, alive on day 3. Primary outcome is development of severe NEC, compared in infants receiving early antibiotics (days 1-2 after birth) and those not. Subgroup analysis on duration of early antibiotic exposure will also occur. Secondary outcomes are: late onset sepsis, total antibiotic use, predischarge mortality, retinopathy of prematurity, intraventricular haemorrhage, bronchopulmonary dysplasia, focal intestinal perforation and any abdominal surgery. To address competing risks, incidence of death before day 7, 14 and 28 will be analysed. We will perform logistic regression and propensity score matched analyses. Statistical analyses will be guided by NEC risk factors, exposures and outcome presented in a causal diagram. These covariates include but are not limited to gestational age, birth weight, small for gestational age, sex, ethnicity, delivery mode, delivery without labour, Apgar score, early feeding and probiotic use. Sensitivity analyses of alternate NEC definitions, specific antibiotics and time of initiation will occur.

ETHICS AND DISSEMINATION

We will use deidentified data from NNRD, which holds permissions for the original data, from which parents can opt out and seek study-specific research ethics approval. The results will help to determine optimal use of early antibiotics for very preterm infants.

IMPLICATIONS

This data will help optimise early antibiotic use in preterm infants.

TRIAL REGISTRATION NUMBER

ISRCTN55101779.

Intra-Amniotic Administration-An Emerging Method to Investigate Necrotizing Enterocolitis, In Vivo (Gallus gallus)

Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease in premature infants and a leading cause of death in neonates (1-7% in the US). NEC is caused by opportunistic bacteria, which cause gut dysbiosis and inflammation and ultimately result in intestinal necrosis. Previous studies have utilized the rodent and pig models to mimic NEC, whereas the current study uses the in vivo (Gallus gallus) intra-amniotic administration approach to investigate NEC. On incubation day 17, broiler chicken (Gallus gallus) viable embryos were injected intra-amniotically with 1 mL dextran sodium sulfate (DSS) in H₂O. Four treatment groups (0.1%, 0.25%, 0.5%, and 0.75% DSS) and two controls (H₂O/non-injected controls) were administered. We observed a significant increase in intestinal permeability and negative intestinal morphological changes, specifically, decreased villus surface area and goblet cell diameter in the 0.50% and 0.75% DSS groups. Furthermore, there was a significant increase in pathogenic bacterial (E. coli spp. and Klebsiella spp.) abundances in the 0.75% DSS group compared to the control groups, demonstrating cecal microbiota dysbiosis. These results demonstrate significant physiopathology of NEC and negative bacterial-host interactions within a premature gastrointestinal system. Our present study demonstrates a novel model of NEC through intra-amniotic administration to study the effects of NEC on intestinal functionality, morphology, and gut microbiota in vivo.

Amino acids for the prevention of mortality and morbidity in preterm infants: a systematic review and network meta-analysis

To determine the effectiveness and safety of amino acids in preventing the mortality and morbidity among preterm infants. We conducted a systematic review and network meta-analysis. We searched MEDLINE, EMBASE, Web of Science, CINAHL, Scopus, Cochrane, and Google Scholar, and grey literature, from databases inception to January 2021. We included randomized trials that evaluated any amino acids on preterm or low-birth weight infants. We performed frequentist pairwise and network meta-analyses and used the GRADE methodology to assess the certainty of the evidence and provide a summary of the results.We included 18 trials (3702 infants). Low certainty evidence showed that there seems to be no benefit for arginine, glutamine, or N-acetylcysteine in reducing all-cause mortality. Oral arginine likely results in reduction of necrotizin enterocolitis (NEC) stage ≥ II (OR 0.48; 95% CI 0.26-0.90; moderate certainty). Oral glutamine may reduce the likelihood of developing late-onset sepsis (LOS) compared to placebo (OR 0.62; 95% CI 0.47-0.82; low certainty); and likely reduces time to reach full enteral feeding (MD = - 2.63 days; 95% CI - 4.99 to - 0.27; moderate certainty). Amino acids may have no effect on mortality. Oral arginine may reduce severe NEC, and oral glutamine may reduce LOS and the time to reach full feeding.Systematic review registration: PROSPERO registration number: CRD4201603873.

Probiotic Use in Preterm Neonates: A Review and Bibliometric Analysis

Background: Necrotizing enterocolitis (NEC) is a major health burden in peterm neonates with mortality rates between 21% and 50%. Prophylaxis is of primary importance as early diagnosis is hindered by the lack of specific signs and laboratory markers. Although probiotics have been routinely used for NEC prophylaxis in neonatal intensive care units around the world, clinical trials provide contradictory data, which fuels an ongoing debate about their efficacy and safety.

Aims: To perform a review and bibliometric analysis on available clinical trials and case reports data on the safety and efficacy of probiotics in preterm neonates and identify relevant publication trends and patterns.

Methods: A bibliometric search for publications on the topic was performed in the Web of Science Core Collection database and the resulting records analyzed in bibliometrix package in R.

Results: Trends in publication activity, historical direct citation network relationships and keyword co-ocurrences were discussed in the context of the most recent therapeutic recommendations.

Conclusion: We took a round view of the potential drawbacks to probiotic use in preterm infants and their possible solutions.

Association of necrotizing enterocolitis with antimicrobial exposure in preterm infants <32 weeks gestational age:A multicenter prospective case-control study

Objective: To assess the risk of necrotizing enterocolitis (NEC) and explore the relationship between antibiotic overexposure and disease occurrence in a large prospective birth cohort.

Methods: Based on a prospective birth cohort, the study collected hospitalization data of very preterm infants (VPIs) having gestational age of less than 32 weeks from January 1, 2018, to June 30, 2021 via the China Northern Neonatal Network. Infants diagnosed with NEC ≥ stage II were included in the case group, and each case was matched for GA and birth weight for the control group. Furthermore, the risk factors for NEC were determined by statistical analyses.

Results: A total of 6425 VPIs were included in this study, and 167 (2.6%) of these subjects were diagnosed with NEC ≥ stage II. The study also included 984 extremely preterm infants (gestational age &lt;28 weeks), including 50 (5.1%) infants diagnosed with NEC ≥ stage II. In the matched case-control study, subjects had a total of antibiotic days-of-therapy for 9015 days, of which broad-spectrum antibiotics (BSAs) accounted for 77%. The antibiotic spectrum index per antibiotic day in the case group was significantly higher and was an independent risk factor for the occurrence of NEC (p = 0.001, OR = 1.13).

Conclusion: The cohort of VPIs was overexposed to antiboitics. Unreasonable combination of antibiotics and overexposure to BSAs may increase the risk of NEC in preterm infants.

Emerging prediction methods for early diagnosis of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a life-threatening disease of the digestive system that occurs in the neonatal period. NEC is difficult to diagnose early and the prognosis is poor. Previous studies have reported that abnormalities can be detected before the presentation of clinical symptoms. Based on an analysis of literature related to the early prediction of NEC, we provide a detailed review on the early prediction and diagnosis methods of NEC, including ultrasound, near-infrared spectroscopy, biomarkers, and intestinal microbiota. This review aimed to provide a reference for further research and clinical practice.

Protective Effects and Mechanism of a Novel Probiotic Strain Ligilactobacillus salivarius YL20 against Cronobacter sakazakii-Induced Necrotizing Enterocolitis In Vitro and In Vivo

Exposure to probiotics in early life contributes to host intestinal development and prevention of necrotizing enterocolitis (NEC). Cronobacter sakazakii (C. sakazakii), an opportunistic pathogen, can cause NEC, bacteremia, and meningitis in neonates, but the research of probiotics against C. sakazakii is limited relative to other enteropathogens. Here, the protective effect and mechanism of a novel probiotic Ligilactobacillus salivarius (L. salivarius) YL20 isolated from breast milk on C. sakazakii-induced intestinal injury were explored by using two in vitro models, including an C. sakazakii-infected intestinal organoid model and intestinal barrier model, as well as an in vivo experimental animal model. Our results revealed that L. salivarius YL20 could promote epithelial cell proliferation in intestinal organoids, rescue budding-impaired organoids, prevent the decrease of mRNA levels of leucine-rich repeat containing G protein-coupled receptor 5 (Lgr5), zonula occludens-1 (Zo-1) and Occludin, and reverse C. sakazakii-induced low level of Mucin 2 (MUC2) in intestinal organoids. Additionally, YL20 could inhibit C. sakazakii invasion, increase the expression of ZO-1 and occludin in C. sakazakii-infected HT-29 cells, and reverse TEER decrease and corresponding permeability increase across C. sakazakii-infected Caco-2 monolayers. Furthermore, YL20 administration could alleviate NEC in C. sakazakii-infected neonatal mice by increasing the mice survival ratio, decreasing pathology scores, and downregulating pro-inflammatory cytokines. Meanwhile, YL20 could also enhance intestinal barrier function in vivo by increasing the number of goblet cells, the level of MUC-2 and the expression of ZO-1. Our overall findings demonstrated for the first time the beneficial effects of L. salivarius YL20 against C. sakazakii-induced NEC by improving intestinal stem cell function and enhancing intestinal barrier integrity.

Effect of a Multi-Strain Probiotic on the Incidence and Severity of Necrotizing Enterocolitis and Feeding Intolerances in Preterm Neonates

Background: Necrotizing enterocolitis (NEC) is a multifactorial disease, causing inflammation of the bowel. The exact root of NEC is still unknown, but a low weight and gestational age at birth are known causes. Furthermore, antibiotic use and abnormal bacterial colonization of the premature gut are possible causes. Premature neonates often experience feeding intolerances that disrupts the nutritional intake, leading to poor growth and neurodevelopmental impairment. Methods: We conducted a double-blind, placebo-controlled, randomized clinical trial to investigate the effect of a multi-strain probiotic formulation (LabinicTM) on the incidence and severity of NEC and feeding intolerances in preterm neonates. Results: There were five neonates in the placebo group who developed NEC (Stage 1A−3B), compared to no neonates in the probiotic group. Further, the use of probiotics showed a statistically significant reduction in the development of feeding intolerances, p < 0.001. Conclusion: A multi-strain probiotic is a safe and cost-effective way of preventing NEC and feeding intolerances in premature neonates.

[Establishment of a nomogram model for predicting necrotizing enterocolitis in very preterm infants]

OBJECTIVES

To investigate the risk factors for necrotizing enterocolitis (NEC) in very preterm infants and establish a nomogram model for predicting the risk of NEC.

METHODS

A total of 752 very preterm infants who were hospitalized from January 2015 to December 2021 were enrolled as subjects, among whom 654 were born in 2015-2020 (development set) and 98 were born in 2021 (validation set). According to the presence or absence of NEC, the development set was divided into two groups: NEC (n=77) and non-NEC (n=577). A multivariate logistic regression analysis was used to investigate the independent risk factors for NEC in very preterm infants. R software was used to plot the nomogram model. The nomogram model was then validated by the data of the validation set. The receiver operating characteristic (ROC) curve, the Hosmer-Lemeshow goodness-of-fit test, and the calibration curve were used to evaluate the performance of the nomogram model, and the clinical decision curve was used to assess the clinical practicability of the model.

RESULTS

The multivariate logistic regression analysis showed that neonatal asphyxia, sepsis, shock, hypoalbuminemia, severe anemia, and formula feeding were independent risk factors for NEC in very preterm infants (P<0.05). The ROC curve of the development set had an area under the curve (AUC) of 0.833 (95%CI: 0.715-0.952), and the ROC curve of the validation set had an AUC of 0.826 (95%CI: 0.797-0.862), suggesting that the nomogram model had a good discriminatory ability. The calibration curve analysis and the Hosmer-Lemeshow goodness-of-fit test showed good accuracy and consistency between the predicted value of the model and the actual value.

CONCLUSIONS

Neonatal asphyxia, sepsis, shock, hypoalbuminemia, severe anemia, and formula feeding are independent risk factors for NEC in very preterm infant. The nomogram model based on the multivariate logistic regression analysis provides a quantitative, simple, and intuitive tool for early assessment of the development of NEC in very preterm infants in clinical practice.

Bench to bedside - new insights into the pathogenesis of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the leading cause of death and disability from gastrointestinal disease in premature infants. Recent discoveries have shed light on a unifying theorem to explain the pathogenesis of NEC, suggesting that specific treatments might finally be forthcoming. A variety of experiments have highlighted how the interaction between bacterial signalling receptors on the premature intestine and an abnormal gut microbiota incites a pro-inflammatory response in the intestinal mucosa and its underlying endothelium that leads to NEC. Central amongst the bacterial signalling receptors implicated in NEC development is the lipopolysaccharide receptor Toll-like receptor 4 (TLR4), which is expressed at higher levels in the premature gut than in the full-term gut. The high prenatal intestinal expression of TLR4 reflects the role of TLR4 in the regulation of normal gut development, and supports additional studies indicating that NEC develops in response to signalling events that occur in utero. This Review provides new evidence explaining the pathogenesis of NEC, explores new findings indicating that NEC development has origins before birth, and discusses future questions and opportunities for discovery in this field.

Neurologic consequences of neonatal necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease of the premature infant with high mortality and morbidity. Children who survive NEC have been shown to demonstrate neurodevelopmental delay, with significantly worse outcomes than from prematurity alone. The pathways leading to NEC-associated neurological impairments remain unclear, limiting the development of preventative and protective strategies. This review aims to summarize the existing clinical and experimental studies related to NEC-associated brain injury. We describe the current epidemiology of NEC, reported long-term neurodevelopmental outcomes among survivors, and proposed pathogenesis of brain injury in NEC. Highlighted are the potential connections between hypoxia-ischemia, nutrition, infection, gut inflammation, and the developing brain in NEC.

Discriminating necrotising enterocolitis and focal intestinal perforation

Discriminating necrotising enterocolitis (NEC) and focal intestinal perforation (FIP) is important for clinical trials, observational cohorts, quality improvement and aetiological understanding. Literature suggests that timing and key features diagnose and discriminate, and that NEC subclassifications exist. We used a detailed 10-year cohort of NEC and FIP cases in preterm infants born <32 weeks' gestation from a single centre to explore antecedent factors, presentation and potential NEC subclassifications. 785 infants had 144 episodes of NEC and 38 of FIP. FIP presented earlier than NEC, but ranges overlapped, and 30% of NEC presented before day 14. Antecedent events (other than feed volumes) and outcomes did not differ between NEC and FIP. Currently used diagnostic/discriminatory features performed poorly, and subclassification identified few cases except transfusion-associated NEC. Contrary to existing literature, postnatal age at NEC presentation was not dependent on gestational age. Detailed review rather than simple definitions are required to separate NEC from FIP.

Longitudinal gut virome analysis identifies specific viral signatures that precede necrotizing enterocolitis onset in preterm infants

Necrotizing enterocolitis (NEC) is a serious consequence of preterm birth and is often associated with gut bacterial microbiome alterations. However, little is known about the development of the gut virome in preterm infants, or its role in NEC. Here, using metagenomic sequencing, we characterized the DNA gut virome of 9 preterm infants who developed NEC and 14 gestational age-matched preterm infants who did not. Infants were sampled longitudinally before NEC onset over the first 11 weeks of life. We observed substantial interindividual variation in the gut virome between unrelated preterm infants, while intraindividual variation over time was significantly less. We identified viral and bacterial signatures in the gut that preceded NEC onset. Specifically, we observed a convergence towards reduced viral beta diversity over the 10 d before NEC onset, which was driven by specific viral signatures and accompanied by specific viral-bacterial interactions. Our results indicate that bacterial and viral perturbations precede the sudden onset of NEC. These findings suggest that early life virome signatures in preterm infants may be implicated in NEC.

A quality improvement initiative to standardize time to initiation of enteral feeds after non-surgical necrotizing enterocolitis using a consensus-based guideline

BACKGROUND

Recent evidence demonstrates that earlier feeding may be beneficial after non-surgical necrotizing enterocolitis (NEC). We aimed to decrease time to reach full enteral feeds by 20% post-NEC by standardizing time to reinitiate feeds.

METHODS

We implemented a consensus-based guideline for earlier feeding post-NEC. Outcome measures included days to initiate enteral feeds and reach full enteral feeds. Central venous line days and length of stay were also evaluated. Balancing measures were NEC recurrence and post-NEC stricture. Statistical analysis used process control methodology and standard comparison statistical testing.

RESULTS

Average days infants with Stage II NEC began feeding decreased from 9.4 to 5.1 days and average days to reach full feeds was decreased by 35% from 24.0 to 15.7 days. We observed no change in our balancing measures.

CONCLUSION

A multidisciplinary consensus-based NEC earlier feeding guideline decreased time to reach full enteral feeds and reduced central line days without adverse events.

Intestinal perfusion assessed by quantitative fluorescence angiography in piglets with necrotizing enterocolitis

BACKGROUND

Reduced intestinal perfusion is thought to be a part of the pathogenesis in necrotizing enterocolitis (NEC). This study aims to evaluate the intestinal perfusion assessment in NEC-lesions by quantitative fluorescence angiography with indocyanine green (q-ICG) during laparoscopy and open surgery.

METHODS

Thirty-four premature piglets were delivered by cesarean section and fed with parenteral nutrition and increasing infant formula volumes to induce NEC. During surgery, macroscopic NEC-lesions were evaluated using a validated macroscopic scoring system (1-6 for increasing NEC severity). The intestinal perfusion was assessed by q-ICG and quantified with a validated pixel intensity computer algorithm.

RESULTS

Significantly higher perfusion values were found in healthy areas of the colon (score 1) compared to those with NEC scores of 4, 5, and 6 (p < 0.05). Similarly, in the small intestine, perfusion was higher in the intestine with areas scored 1 compared to scores of 3 and 4 (p < 0.05). A cut-off value was found between NEC score of 1-2 vs. 3-4 for the small intestine at 117 and for colon at 107 between NEC scores 12 vs. scores of 36 with an area less than the curve value at 0.9 (p < 0.05).

CONCLUSIONS

q-ICG seems to be a feasible and valuable technique to evaluate the perfusion of tissue with NEC-lesions. We found a cut-off between intestine with scores 1-2 and intestine with NEC scores 3-6 in colon, and NEC score 3-4 in the small intestine.

LEVEL OF EVIDENCE

II.

Development of the Gastrointestinal Tract in Newborns as a Challenge for an Appropriate Nutrition: A Narrative Review

The second and third trimesters of pregnancy are crucial for the anatomical and functional development of the gastrointestinal (GI) tract. If premature birth occurs, the immaturity of the digestive and absorptive processes and of GI motility represent a critical challenge to meet adequate nutritional needs, leading to poor extrauterine growth and to other critical complications. Knowledge of the main developmental stages of the processes involved in the digestion and absorption of proteins, carbohydrates, and lipids, as well as of the maturational phases underlying the development of GI motility, may aid clinicians to optimize the nutritional management of preterm infants. The immaturity of these GI systems and functions may negatively influence the patterns of gut colonization, predisposing to an abnormal microbiome. This, in turn, further contributes to alter the functional, immune, and neural development of the GI tract and, especially in preterm infants, has been associated with an increased risk of severe GI complications, such as necrotizing enterocolitis. Deeper understanding of the physiological colonization patterns in term and preterm infants may support the promotion of these patterns and the avoidance of microbial perturbations associated with the development of several diseases throughout life. This review aims to provide a global overview on the maturational features of the main GI functions and on their implications following preterm birth. We will particularly focus on the developmental differences in intestinal digestion and absorption functionality, motility, gut–brain axis interaction, and microbiomes.

Synbiotics to prevent necrotising enterocolitis in very preterm or very low birth weight infants

BACKGROUND

Intestinal dysbiosis may contribute to the pathogenesis of necrotising enterocolitis (NEC) in very preterm or very low birth weight (VLBW) infants. Dietary supplementation with synbiotics (probiotic micro-organisms combined with prebiotic oligosaccharides) to modulate the intestinal microbiome has been proposed as a strategy to reduce the risk of NEC and associated mortality and morbidity.

OBJECTIVES

To assess the effect of enteral supplementation with synbiotics (versus placebo or no treatment, or versus probiotics or prebiotics alone) for preventing NEC and associated morbidity and mortality in very preterm or VLBW infants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, the Maternity and Infant Care database and CINAHL, from earliest records to 17 June 2021. We searched clinical trials databases and conference proceedings, and examined the reference lists of retrieved articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs comparing prophylactic synbiotics supplementation with placebo or no synbiotics in very preterm (< 32 weeks' gestation) or very low birth weight (< 1500 g) infants.

DATA COLLECTION AND ANALYSIS

Two review authors separately performed the screening and selection process,  evaluated risk of bias of the trials, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference, with associated 95% confidence intervals (CIs). We used the GRADE approach to assess the level of certainty for effects on NEC, all-cause mortality, late-onset invasive infection, and neurodevelopmental impairment.

MAIN RESULTS

We included six trials in which a total of 925 infants participated. Most trials were small (median sample size 200). Lack of clarity on methods used to conceal allocation and mask caregivers or investigators were potential sources of bias in four of the trials. The studied synbiotics preparations contained lactobacilli or bifidobacteria (or both) combined with fructo- or galacto-oligosaccharides (or both).  Meta-analyses suggested that synbiotics may reduce the risk of NEC (RR 0.18, 95% CI 0.09 to 0.40; RD 70 fewer per 1000, 95% CI 100 fewer to 40 fewer; number needed to treat for an additional beneficial outcome (NNTB) 14, 95% CI 10 to 25; six trials (907 infants); low certainty evidence); and all-cause mortality prior to hospital discharge (RR 0.53, 95% CI 0.33 to 0.85; RD 50 fewer per 1000, 95% CI 120 fewer to 100 fewer; NNTB 20, 95% CI 8 to 100; six trials (925 infants); low-certainty evidence). Synbiotics may have little or no effect on late-onset invasive infection, but the evidence is very uncertain (RR 0.84, 95% CI 0.58 to 1.21; RD 20 fewer per 1000, 95% CI 70 fewer to 30 more; five trials (707 infants); very low-certainty evidence). None of the trials assessed neurodevelopmental outcomes. In the absence of high levels of heterogeneity, we did not undertake any subgroup analysis (including the type of feeding).

AUTHORS' CONCLUSIONS

The available trial data provide only low-certainty evidence about the effects of synbiotics on the risk of NEC and associated morbidity and mortality for very preterm or very low birth weight infants. Our confidence in the effect estimates is limited; the true effects may be substantially different from these estimates. Large, high-quality trials would be needed to provide evidence of sufficient validity and applicability to inform policy and practice.

Necrotizing Enterocolitis and Its Predictors Among Preterm Neonates Admitted in Neonatal Intensive Care Units of Gurage Zone Public Hospitals, Southwest Ethiopia, 2021

Background

Necrotizing Enter colitis (NEC) is the most common multifactorial and devastating gastrointestinal emergency which primarily affects premature infants. The purpose of this study was to identify the prevalence of Necrotizing Enterocolitis and its associated factors among preterm neonates admitted to Neonatal Intensive Care Units in Gurage Zone hospitals.

Methods

Institution-based cross-sectional study design was employed. The simple Random Sampling Technique was applied to collect the data using a structured questionnaire. Data were cleaned, checked for inconsistencies, coded and entered via EPI data 3.1, and exported to Stata version 14 for further analysis. The data were processed by Stata 14 to estimate the prevalence of necrotizing enterocolitis.

Results

The prevalence of Necrotizing Enterocolitis among neonates was 28 (9.7%) 95% CI of 6. 8–13.7%. Birth weight (AOR: 7.33 95% CI (2.04: 26.38)), presence of maternal infection (AOR: 6.09, 95% CI (1.31:28.26)), length of hospital stay (AOR: 3.28, 95% CI (1.20, 8.96)), and initiating trophic feeding (AOR: 5.89, 95% CI (2.27: 15.33)) were associated with neonatal necrotizing enterocolitis.

Conclusion

The prevalence of Necrotizing Enterocolitis among preterm neonates was significant and special attention is needed for premature neonates with low birth weight and born from mothers with infection during pregnancy. Minimizing the length of hospital stay will be very useful to prevent the occurrence of Necrotizing Enterocolitis.

Providing the Best Parenteral Nutrition before and after Surgery for NEC: Macro and Micronutrients Intakes

Necrotizing enterocolitis (NEC) is the main gastrointestinal emergency of preterm infants for whom bowel rest and parenteral nutrition (PN) is essential. Despite the improvements in neonatal care, the incidence of NEC remains high (11% in preterm newborns with a birth weight <1500 g) and up to 20−50% of cases still require surgery. In this narrative review, we report how to optimize PN in severe NEC requiring surgery. PN should begin as soon as possible in the acute phase: close fluid monitoring is advocated to maintain volemia, however fluid overload and electrolytes abnormalities should be prevented. Macronutrients intake (protein, glucose, and lipids) should be adequately guaranteed and is essential in each phase of the disease. Composite lipid emulsion should be the first choice to reduce the risk of parenteral nutrition associated liver disease (PNALD). Vitamin and trace elements deficiency or overload are frequent in long-term PN, therefore careful monitoring should be planned starting from the recovery phase to adjust their parenteral intake. Neonatologists must be aware of the role of nutrition especially in patients requiring long-term PN to sustain growth, limiting possible adverse effects and long-term deficiencies.

The predictors of necrotizing enterocolitis in newborns with low birth weight: A retrospective analysis

There are needs to investigate the influencing factors of necrotizing enterocolitis (NEC) in low birth weight (LBW) newborns, to provide insights into the clinical management of NEC.This study was a retrospective cohort study. Infants admitted to our hospital from January 1, 2019 to June 30, 2021 were selected. The clinical characteristics of NEC and no-NEC infants were evaluated. Logistic regression analyses were conducted to assess the risk factors of NEC in LBW infants.A total of 192 LBW infants were included, the incidence of NEC in LBW infants was 35.42%. There were significant differences in the congenital heart disease, sepsis, breastfeeding, blood transfusion and probiotics feeding between NEC and no-NEC group (all P < .05), and there were no significant differences in birth weight, gestational age, mother's pregnancy-induced hypertension, premature rupture of fetal membrane, amniotic fluid pollution, fetal asphyxia, neonatal respiratory distress syndrome and mechanical ventilation between NEC and no-NEC group (all P > .05). Congenital heart disease (OR: 2.128, 95% CI: 1.103-3.511), sepsis (OR: 1.630, 95% CI: 1.022-2.549), and blood transfusion (OR: 1.451, 95% CI: 1.014-2.085) were the independent risk factors for NEC in LBW infants, and breastfeeding (OR: 0.494, 95% CI: 0.023-0.928), probiotics feeding (OR: 0.816, 95% CI: 0.782-0.982) were the protective factors for the NEC in LBW infants. The prognosis of NEC infants undergone surgery treatment was better than that of infants undergone conservative treatments (P = .043).The incidence of NEC in LBW is high, which is affected by many factors, and comprehensive interventions targeted on the risk and protective factors should be made to improve the prognosis of LBW infants.

A mini-review of advances in intestinal flora and necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a digestive disease that frequently occurs in premature infants with low gestational age and low birth weight, and seriously threatens the life of NEC patients. NEC pathogenesis is recognized to be affected by multiple factors, such as preterm birth, formula feeding, and low birth weight. As a popular object for the past decades, intestinal flora is commonly used in NEC-related studies, and intestinal disorder is considered as a critical risk factor for the occurrence and development of NEC. The colonization of abnormal microbiota into gastrointestinal micro-ecosystem can easily lead to the damage of intestinal mucosal barrier, destruction of immune function, inflammatory reaction, and further the occurrence of NEC. Although it is a low-cost and safe way to prevent and treat the NEC by early intervention of oral probiotics to regulate the intestinal homeostasis, more studies in the future are still encouraged to narrow the gap between theoretical guidance and practical application.

Antibiotics in the medical and surgical treatment of necrotizing enterocolitis. A systematic review

BACKGROUND

The aim of this review was to identify relevant randomized controlled trials (RCTs) and non-RCTs to evaluate the existing knowledge on the effect of antibiotic treatment for infants with necrotizing enterocolitis (NEC).

OBJECTIVE

Identifying 1) the best antibiotic regimen to avoid disease progression as assessed by surgery or death, 2) the best antibiotic regimen for infants operated for NEC as assessed by re-operation or death.

METHODS

Embase, MEDLINE and Cochrane were searched systematically for human studies using antibiotics for patients with NEC, Bell's stage II and III.

RESULTS

Five studies were included, with a total of 375 infants. There were 2 RCT and 3 cohort studies. Four main antibiotic regimens appeared. Three with a combination of ampicillin + gentamycin (or similar) with an addition of 1) clindamycin 2) metronidazole or 3) enteral administration of gentamycin. One studied investigated cefotaxime + vancomycin. None of the included studies had a specific regimen for infants undergoing surgery.

CONCLUSIONS

No sufficient evidence was found for any recommendation on the choice of antibiotics, the route of administration or the duration in infants treated for NEC with Bell's stage II and III.

Delayed introduction of progressive enteral feeds to prevent necrotising enterocolitis in very low birth weight infants

BACKGROUND

Enteral feeding for very preterm or very low birth weight (VLBW) infants is often delayed for several days after birth due to concern that early introduction of feeding may not be tolerated and may increase the risk of necrotising enterocolitis. Concerns exist, however, that delaying enteral feeding may diminish the functional adaptation of the gastrointestinal tract and prolong the need for parenteral nutrition with its attendant infectious and metabolic risks.

OBJECTIVES

To determine the effects of delayed introduction of progressive enteral feeds on the risk of necrotising enterocolitis, mortality and other morbidities in very preterm or VLBW infants.

SEARCH METHODS

Search strategies were developed by an information specialist in consultation with the review authors. The following databases were searched in October 2021 without date or language restrictions: CENTRAL (2021, Issue 10), MEDLINE via OVID (1946 to October 2021), Embase via OVID (1974 to October 2021), Maternity and Infant Care via OVID (1971 to October 2021), CINAHL (1982 to October 2021). We also searched for eligible trials in clinical trials databases, conference proceedings, previous reviews, and reference lists of retrieved articles.

SELECTION CRITERIA

Randomised controlled trials that assessed the effects of delayed (four or more days after birth) versus earlier introduction of progressive enteral feeds on necrotising enterocolitis, mortality and other morbidities in very preterm or VLBW infants.

DATA COLLECTION AND ANALYSIS

Two review authors separately evaluated trial risk of bias, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference. We used the GRADE approach to assess the certainty of evidence for effects on necrotising enterocolitis, mortality,  feed intolerance, and invasive infection.

MAIN RESULTS

We included 14 trials in which a total of 1551 infants participated. Potential sources of bias were lack of clarity on methods to generate random sequences and conceal allocation in half of the trials, and lack of masking of caregivers or investigators in all of the trials. Trials typically defined delayed introduction of progressive enteral feeds as later than four to seven days after birth and early introduction as four days or fewer after birth. Infants in six trials (accounting for about half of all of the participants) had intrauterine growth restriction or circulatory redistribution demonstrated by absent or reversed end-diastolic flow velocities in the fetal aorta or umbilical artery.  Meta-analyses showed that delayed introduction of progressive enteral feeds may not reduce the risk of necrotising enterocolitis (RR 0.81, 95% confidence interval (CI) 0.58 to 1.14; RD -0.02, 95% CI -0.04 to 0.01; 13 trials, 1507 infants; low-certainty evidence due risk of bias and imprecision) nor all-cause mortality before hospital discharge (RR 0.97, 95% CI 0.70 to 1.36; RD -0.00, 95% CI -0.03 to 0.03; 12 trials, 1399 infants; low-certainty evidence due risk of bias and imprecision). Delayed introduction of progressive enteral feeds may slightly reduce the risk of feed intolerance (RR 0.81, 95% CI 0.68 to 0.97; RD -0.09, 95% CI -0.17 to -0.02; number needed to treat for an additional beneficial outcome = 11, 95% CI 6 to 50; 6 trials, 581 infants; low-certainty evidence due to risk of bias and imprecision) and probably increases the risk of invasive infection (RR 1.44, 95% CI 1.15 to 1.80; RD 0.10, 95% CI 0.04 to 0.15; number needed to treat for a harmful outcome = 10, 95% CI 7 to 25; 7 trials, 872 infants; moderate-certainty evidence due to risk of bias).  AUTHORS' CONCLUSIONS: Delaying the introduction of progressive enteral feeds beyond four days after birth (compared with earlier introduction) may not reduce the risk of necrotising enterocolitis or death in very preterm or VLBW infants. Delayed introduction may slightly reduce feed intolerance, and probably increases the risk of invasive infection.

Development and Validation of a Nomogram for Predicting the Risk of Bell's Stage II/III Necrotizing Enterocolitis in Neonates Compared to Bell's Stage I

BACKGROUND

Patients with Bell's Stage II/III necrotizing enterocolitis (NEC) may have more severe presentations, higher rates of death, and more long-term complications than those with Bell's Stage I NEC, so the purpose of this article was to construct a nomogram model to distinguish Bell's stage II/III NEC early from Bell's Stage I NEC, which is critical in the clinical management of NEC.

PATIENTS AND METHODS

A total of 730 NEC newborns diagnosed from January 2015 to January 2021 were retrospectively studied. They were randomly divided into training and validation groups at the ratio of 7:3. A nomogram model for predicting NEC was developed based on all the independent risk factors by multivariate regression analysis. The model's performance was mainly evaluated through three aspects: the area under the curve (AUC) to verify discrimination, the Hosmer-Lemeshow test and calibration curve to validate the consistency, and decision curve analysis (DCA) to determine the clinical effectiveness.

RESULTS

Predictors included in the prediction model were gestational age (GA), birth weight (BW), asphyxia, septicemia, hypoglycemia, and patent ductus arteriosus (PDA). This nomogram model containing the above-mentioned six risk factors had good discrimination ability in both groups, and the AUCs were 0.853 (95% CI, 0.82-0.89) and 0.846 (95% CI, 0.79-0.90), respectively. The calibration curve and DCA confirmed that the nomogram had good consistency and clinical usefulness.

CONCLUSIONS

This individual prediction nomogram based on GA, BW, asphyxia, septicemia, hypoglycemia, and PDA served as a useful tool to risk-stratify patients with NEC, and can help neonatologists early distinguish Bell's stage II/III NEC early from Bell's Stage I NEC.

Effect of Oropharyngeal Administration of Colostrum in Premature Newborns ≤32 Weeks of Gestation on the Immune Response and Neonatal Morbidity: A Double-Blind Randomized Clinical Trial

INTRODUCTION

The mother's colostrum carries immunological components, such as cytokines and immunoglobulins (Igs), derived from the maternal circulation with bacteriostatic properties.

OBJECTIVE

The objective of this study was to evaluate the effect of oropharyngeal administration of colostrum (OPAC) vs. placebo in the first 4 days of life in premature newborns ≤32 weeks of gestation on serum Ig concentration, neonatal morbidity, and total days of hospitalization.

HYPOTHESIS

The OPAC increases serum Igs and decreases morbidity and total days of hospitalization.

MATERIALS AND METHODS

A double-blind randomized controlled trial was carried out. Participants were randomly assigned to one of the two groups, namely, group 1: placebo (P) (n = 50) and group 2: colostrum (C) (n = 46). A blood sample was obtained at baseline and 7 and 28 days of life to quantify immunoglobulin G (IgG), immunoglobulin A (IgA), and IgM. Results: The C group showed an increase in serum IgA on day 28 expressed as median and [interquartile range]; C: 25 [12-35] vs. P: 11 [8-18], p < 0.001. There were no significant differences in neonatal morbidity. Newborns in the colostrum group showed the completed enteral feeding earlier (days), C: 13.9 ± 7 vs. P: 17.4 ± 8.4, p < 0.04; they reached the birth weight earlier, C: 10.9 ± 2.8 vs. P: 12.9 ± 4, p < 0.01, and had less days of hospitalization, C: 60.2 ± 33.8 vs. P: 77.2 ± 47.3, p < 0.04. Neonatal mortality was lower in the colostrum group than the placebo group 0% vs. 12%, respectively, without a statistical difference (p = 0.06).

CONCLUSION

In premature newborns ≤32 weeks of gestation, the OPAC within 4 days after birth increases serum IgA concentration at day 28 compared to placebo. Similarly, OPAC decreased the days to complete enteral feeding and reach the birth weight and total days of hospitalization.

CLINICAL TRIAL REGISTRATION

[https://clinicaltrials.gov/ct2/show/NCT03578341], identifier: [NCT03578341].

Risk factors for mortality in preterm infants with necrotizing enterocolitis: a retrospective multicenter analysis

It is difficult to predict the risk of mortality in necrotizing enterocolitis (NEC). This study aimed at identifying risk factors for severe NEC (Bell stage III) and mortality in preterm children with NEC. In this multicenter retrospective study, we analyzed multiple data from 157 premature children with confirmed NEC in the period from January 2007 to October 2018. We performed univariate, multivariate, stepwise logistic regression, and receiver operator characteristics (ROC) analyses. We were able to demonstrate that low Apgar scores (notably at 1' and 5'), low hemoglobin concentration (Hgb), and high lactate level at disease onset and during disease correlated with NEC severity and mortality (P < 0.05, respectively). Severe NEC was related to congenital heart disease (CHD - OR 2.6, CI95% 1.2-5.8, P 0.015) and patent ductus arteriosus (PDA - OR 3.3, CI95% 1.6-6.9, P 0.0012), whereas death was related to the presence of PDA (OR 5.5, CI95% 2.3-14, P < 0.001).Conclusion: Low Apgar scores, low Hgb, high lactate levels, and the presence of CHD or PDA correlated with severe NEC or mortality in children with NEC. What is Known: • It remains difficult to predict which infant that suffers from necrotizing enterocolitis at risk of death. • Several clinical and laboratory parameters tools to predict fatal outcome in NEC. What is New: • The following laboratory parameters were associated with the risk of death from NEC: Hemoglobin concentration, base excess and lactate level. • The following clinical variables were associated with the risk of death from NEC: Apgar scores, as well as the presence of congenital heart disease and patent ductus arteriosus.

Chronological changes of serum exosome in preterm infants: A prospective study

BACKGROUND

Exosomes, which are observed in all human fluid, including serum, are nanosized extracellular vesicles with a mechanism of intercellular communication. Potential clinical applications of exosomes in neonatal diseases have recently been discussed. However, the characteristics of exosomes in serum during early infancy is unclear.

METHODS

In this prospective study, we evaluated the chronological changes in the concentration of serum-derived exosomes of 20 infants for 12 months after birth.

RESULTS

The average concentration of serum-derived exosomes was 4.6 × 10¹⁰ particles/mL at birth and increased significantly until the age of 48 weeks. There was a moderate correlation between the gestational age and the concentration of serum-derived exosomes both at birth (r = 0.54, P = 0.01) and during the 8 weeks after birth (r = 0.48, P < 0.001). A multivariable analysis showed that gestational age at birth was associated with the concentration of serum-derived exosomes at birth (partial regression coefficient, 0.86; 95% confidence interval, 0.37-1.37; P = 0.002).

CONCLUSIONS

The concentration of serum-derived exosomes in preterm infants increased both chronologically and by gestational age after birth. These basic data may help to further understand physiology of exosomes in preterm infants.

Fecal HBD-2 and Claudin-3 may be potential biomarkers to predict the deterioration of necrotizing enterocolitis: A prospective study

BACKGROUND AND PURPOSE

Necrotizing enterocolitis (NEC) is a critical gastrointestinal disease. We aim to explore the value of fecal human β-defensin 2 (HBD-2), Claudin-3, high-mobility group box-1 protein (HMGB-1), and resistin-like molecule β (Relmβ) as well as some laboratory metrics to predict the deterioration of NEC.

METHODS

Infants diagnosed with NEC at Stage II were enrolled in our study. Those who progressed to Stage III were included in the Stage III group and the rest were included in the Stage II group. Clinical data and laboratory metrics of the infants were collected. Fecal samples of HBD2, HMGB-1, Claudin-3, and Relmβ collected during their enrollment were determined by using enzyme-linked immunosorbent assay (ELISA) kits. Student's t-test, the Mann-Whitney U test, the chi-square test, receiver operating characteristic (ROC), and logistic regression analysis were performed.

RESULTS

Sixty infants diagnosed with NEC at Stage II were enrolled in our study, with 27 in the Stage III group (n = 27) and 33 in the Stage II group (n = 33). Although many of these NEC cases were late preterm and term infants, the infants in the Stage III group had a lower gestational age (P < 0.05). The incidence of gestational diabetes mellitus, peritonitis, intestinal adhesion, and sepsis was higher and more infants in the Stage III group underwent surgeries (P < 0.05). The levels of HBD-2 and Claudin-3 were higher and neutrophil count was lower in the Stage III group than in the Stage II Group, and the area under the curve (AUC) was 0.754, 0,755, and 0.666, respectively (P < 0.05). HBD-2 ≥ 1649.02 ng/g and Claudin-3 ≥ 2488.71 pg/g were included in the multivariate stepwise logistic regression analysis (P < 0.05), and the AUC of the model was 0.805 (95% CI: 0.688-0.922).

CONCLUSION

Fecal HBD-2 and Claudin-3 may be potential biomarkers to predict the deterioration of NEC from Stage II to Stage III.

Benefits of a Single Dose of Betamethasone in Imminent Preterm Labour

Background: A complete course of prenatal corticosteroids reduces the possibility of morbimortality and neonatal respiratory distress syndrome (RDS). Occasionally, it is not possible to initiate or complete the maturation regimen, and the preterm neonate is born in a non-tertiary hospital. This study aimed to assess the effects of a single dose of betamethasone within 3 h before delivery on serious outcomes (mortality and serious sequelae) and RDS in preterm neonates born in tertiary vs. non-tertiary hospitals. Materials and methods: Preterm neonates who were <35 weeks and ≤1500 g, treated during a period of five years in a level IIIC NICU, were included in this retrospective cohort study. Participants were divided into groups as follows: NM, non-matured; PM, partial maturation (one dose of betamethasone up to 3 h antepartum). They were further divided based on their place of birth (NICU-IIIC vs. non-tertiary hospitals). The morbimortality rates and the severity of neonatal RDS were evaluated. Results: A total of 76 preterm neonates were included. A decrease in serious outcomes was found in the PM group in comparison to the NM group (OR = 0.2; 95%CI (0.07–0.9)), as well as reduced need for mechanical ventilation (54% vs. 68%). The mean time between maternal admission and birth was similar in both cohorts. The mean time from the administration of betamethasone to delivery was 1 h in the PM cohort. With regard to births in NICU-IIIC, the PM group performed better in terms of serious outcomes (32% vs. 45%) and the duration of mechanical ventilation (117.75 vs. 132.18 h) compared to the NM group. In neonates born in non-tertiary hospitals with PM in comparison to the NM group, a trend towards a reduced serious outcome (28.5% vs. 62.2%) and a decreased need for mechanical ventilation (OR = 0.09; 95%CI (0.01–0.8)) and maximum FiO₂ (p = 0.01) was observed. Conclusions: A single dose of betamethasone up to 3 h antepartum may reduce the rate of serious outcomes and the severity of neonatal RDS, especially in non-tertiary hospitals.

The effect of daily probiotics on the incidence and severity of necrotizing enterocolitis in infants with very low birth weight

Background:

Necrotizing enterocolitis remains a leading cause of morbidity and mortality in premature infants. The role of prophylactic probiotics in its prevention is unclear. This study evaluates the effect of routine probiotics on the incidence and severity of necrotizing enterocolitis in infants with very low birth weight in the neonatal intensive care unit.

Methods:

This retrospective cohort study compared infants cared for at a single institution before and after implementation of routine probiotic administration (2014– 2018). Babies born after July 2016 received probiotics containing Bifidobacterium and Lactobacillus daily until 35 weeks corrected gestational age. Baseline characteristics, necrotizing enterocolitis incidence and severity, infections, mortality, and length of stay were compared between groups.

Results:

Of the 665 infants included in the study, 310 received probiotics and 355 did not. The 2 groups did not differ with regard to gestational age, birth anthropometrics, mode of delivery, comorbidities, and type of enteral feed. The incidence of necrotizing enterocolitis (Bell’s stage 2 of 3) was similar between groups (4% v. 5%, p = 0.35), as was its severity (p = 0.10). In addition, there were no significant differences in mortality and length of stay between the groups. Significantly fewer infants receiving probiotics developed infections (27% v. 34%, p = 0.046), with the rate of urinary tract infections having the largest reduction.

Conclusion:

The routine use of Bifidobacterium and Lactobacillus probiotics in infants with very low birth weight did not significantly affect the incidence and severity of necrotizing enterocolitis. However, the use of probiotics was associated with fewer overall infections.

Newborns with Bloody Stools-At the Crossroad between Efficient Management of Necrotizing Enterocolitis and Antibiotic Stewardship

The onset of bloody stools in neonates often results in antibiotic treatment for suspected necrotizing enterocolitis (NEC). Food protein-induced allergic proctocolitis (FPIAP) is an often-neglected differential diagnosis. We performed a retrospective analysis of antibiotic exposure at our tertiary center from 2011 to 2020 that included three time periods of differing antimicrobial stewardship goals. We compared these data with the conventional treatment guidelines (modified Bell's criteria). In our cohort of 102 neonates with bloody stools, the length of antibiotic exposure was significantly reduced from a median of 4 to 2 days. The proportion of treated neonates decreased from 100% to 55% without an increase in negative outcomes. There were 434 antibiotic days. Following a management strategy according to modified Bell's criteria would have led to at least 780 antibiotic days. The delayed initiation of antibiotic treatment was observed in 7 of 102 cases (6.9%). No proven NEC case was missed. Mortality was 3.9%. In conclusion, with FPIAP as a differential diagnosis of NEC, an observational management strategy in neonates with bloody stools that present in a good clinical condition seems to be justified. This may lead to a significant reduction of antibiotic exposure. Further prospective, randomized trials are needed to prove the safety of this observational approach.

Inhibition of Interleukin-6 signaling: A novel therapeutic approach to necrotizing enterocolitis

OBJECTIVES

This study investigated the effects of tocilizumab on the prevention and treatment of experimental necrotizing enterocolitis (NEC) in newborn rats.

METHODS

Forty-two newborn Sprague-Dawley rats were randomly separated into three groups: NEC + placebo, NEC + tocilizumab, and the control group. NEC + placebo and NEC + tocilizumab groups were given 1 mg/kg lipopolysaccharide intraperitoneally once only on the first day, were fed with a special rodent formula every 3 h, inhaled 100% CO2 for 10 min, were exposed to cold stress at + 4 °C for 5 min, and 97% O2 for 5 min twice a day for 3 days. NEC + tocilizumab group was treated with 8 mg/kg/day tocilizumab (Actemra®) intraperitoneally, while NEC + placebo group was given intraperitoneal 0.9% saline at a dose of 2 mL/kg/day from the first day to the end of the study. All newborn rats were sacrificed on day 4. Specimens were taken for histopathologic, immunohistochemical and biochemical evaluation from the ileum and proximal colon.

RESULTS

NEC + tocilizumab group had higher weight gain and survival rate compared to NEC + placebo group and clinical sickness score was reduced in NEC + tocilizumab group (p < 0.05). Lower tissue damage and apoptosis were found in the NEC + tocilizumab group compared to the NEC + placebo group (p < 0.01). Tissue Interleukin-6, Interleukin-1β, TNF-α, myeloperoxidase and caspase-3 levels were significantly decreased in the NEC + tocilizumab group (p < 0.01).

CONCLUSIONS

Tocilizumab could be a potential option in the prevention and treatment of NEC.

Plasma Citrulline as a Biomarker for Early Diagnosis of Necrotizing Enterocolitis in Preterm Infants

OBJECTIVE

Citrulline synthesized by healthy enterocytes and decreases with injury. This work aimed to study plasma citrulline concentrations (CITs) as a biomarker to differentiate among infants presenting with early nonspecific signs and symptoms of necrotizing enterocolitis (NEC) with those who will develop NEC. Further to study the correlation between posttreatment CIT with time to full feeds (TTFF) and length of stay (LOS).

STUDY DESIGN

This is a prospective study which included infants < 32 weeks gestational age (GA) with 9 infants each in Group 1 (stage 2/3 NEC), Group 2 (with stage 1 NEC-like presentation), and Group 3 (healthy GA-matched infants). CIT was measured in Groups 1 and 2 within 24 hours of presentation and again in Group 1 after treatment.

RESULTS

The three groups were similar in clinical characteristics. Median CIT (µmol/L) in Group 1 (15.4 [interquartile range, IQR: 7.3-18.0]) was lower than Group 2 (22.2 [IQR: 18.3-27.3], p = 0.02) and Group 3 (24.9 [IQR: 19.8-31.9], p = 0.009). Posttreatment CIT in Group 1 did not correlate with TTFF (r = 0.15; p = 0.69) and LOS (r =  - 0.33; p = 0.38).

CONCLUSION

CIT was lower in infants with NEC as compared with healthy controls and those infants with nonspecific signs of NEC. CIT after treatment does not correlate with TTFF and LOS.

KEY POINTS

· Citrulline is produced by enterocytes.. · It is decreased in infants with necrotizing enterocolitis early in disease.. · It can be used as a biomarker for early diagnosis of necrotizing enterocolitis..

Short- and Long-Term Implications of Human Milk Microbiota on Maternal and Child Health

Human milk (HM) is considered the most complete food for infants as its nutritional composition is specifically designed to meet infant nutritional requirements during early life. HM also provides numerous biologically active components, such as polyunsaturated fatty acids, milk fat globules, IgA, gangliosides or polyamines, among others; in addition, HM has a “bifidogenic effect”, a prebiotic effect, as a result of the low concentration of proteins and phosphates, as well as the presence of lactoferrin, lactose, nucleotides and oligosaccharides. Recently, has been a growing interest in HM as a potential source of probiotics and commensal bacteria to the infant gut, which might, in turn, influence both the gut colonization and maturation of infant immune system. Our review aims to address practical approaches to the detection of microbial communities in human breast milk samples, delving into their origin, composition and functions. Furthermore, we will summarize the current knowledge of how HM microbiota dysbiosis acts as a short- and long-term predictor of maternal and infant health. Finally, we also provide a critical view of the role of breast milk-related bacteria as a novel probiotic strategy in the prevention and treatment of maternal and offspring diseases.

Human Milk Growth Factors and Their Role in NEC Prevention: A Narrative Review

Growing evidence demonstrates human milk's protective effect against necrotizing enterocolitis (NEC). Human milk derives these properties from biologically active compounds that influence intestinal growth, barrier function, microvascular development, and immunological maturation. Among these protective compounds are growth factors that are secreted into milk with relatively high concentrations during the early postnatal period, when newborns are most susceptible to NEC. This paper reviews the current knowledge on human milk growth factors and their mechanisms of action relevant to NEC prevention. It will also discuss the stability of these growth factors with human milk pasteurization and their potential for use as supplements to infant formulas with the goal of preventing NEC.

Differentiation of food protein-induced enterocolitis syndrome misleading to necrotizing enterocolitis

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a rare non-immunoglobulin E-mediated food allergy with necrotizing enterocolitis (NEC)-like symptoms which requires differential diagnosis as treatments differ.

OBJECTIVE

To evaluate the clinical, laboratory, and radiologic findings that differentiate FPIES from NEC in preterm and term infants.

METHODS

Clinical features, comorbidities, and laboratory and radiologic findings of neonates with presumed NEC were reviewed retrospectively and compared between FPIES and NEC in preterm and term infants who were admitted to the neonatal intensive care unit at Seoul National University Bundang Hospital between May 2003 and February 2020.

RESULTS

A total of 10 of 150 (6.7%) preterm and 17 of 38 (44.7%) term infants with presumed NEC were confirmed to have FPIES; the remainder had NEC by modified Bell's criteria. Demographics and comorbidities were similar between these groups. Symptoms such as hematochezia, shock, leukocytosis, peripheral eosinophilia, and feeding of extensively hydrolyzed milk formula or elemental formula after discharge were significantly different between the 2 groups in term infants (P <.05), but not in preterm infants. On abdominal ultrasonography, pneumatosis intestinalis was more common among preterm FPIES (44.4%) than NEC cases (21.6%) (P =.04). Among the preterm infants, 4 FPIES (40%) and 25 NEC (17.9%) cases required surgery (P =.10).

CONCLUSION

Differentiating FPIES in neonates suspected of having NEC is important as dietary elimination of the triggering milk protein can be recommended instead of prolonged fasting and antibiotic treatment, which are indicated for NEC, in both term and preterm infants.

NIRS as a biomarker of bowel ischaemia & surgical pathology: A meta-analysis of studies in newborns

OBJECTIVE

We performed a meta-analysis on Near-infrared Spectroscopy (NIRS) as a biomarker of bowel ischaemia.

SUMMARY BACKGROUND DATA

NIRS allows non-invasive assessment of gastrointestinal regional oxygen saturation (GrSO₂). Studies to date have focused on the feasibility of NIRS in clinical practice and its reproducibility. GrSO₂ can be used alone, or in conjunction with cerebral NIRS to give a Cerebral Splanchnic Oxygenation Ratio (CSOR). We assess published data on abdominal NIRS as a marker of bowel ischaemia.

METHODS

A literature review was conducted using the PRISMA method. Data on GrSO₂ and CSOR in controls and patients with confirmed ischaemia was included in a meta-analysis, and used to identify a diagnostic threshold.

RESULTS

14 studies were identified. Meta-analysis demonstrated that GrSO₂ (p < 0.01) and CSOR (p < 0.01) were significantly lower in neonates with bowel pathology associated with ischaemia than controls. Area under the curve for GrSO₂ was 0.80, with Youden's index highest (0.52) at a GrSO₂ of 42% (specificity 91% and sensitivity 62%). For CSOR, area under the curve is 0.89, with Youden's index highest (0.69) at 0.76 (specificity of 80%, sensitivity 90%).

CONCLUSIONS

Splanchnic NIRS correlates with bowel ischaemia. Low GrSO₂ is consistently associated with ischaemia, although a specific cut off level in each patient is hard to define. However, values below 42% correlate strongly with ischaemia while values above 52% are more suggestive of patients without bowel pathology. CSOR of below 0.76 is strongly suggestive of ischaemia. Trends within individuals are likely to be able to provide even more clinically correlatable and diagnostic data.

Slow advancement of enteral feed volumes to prevent necrotising enterocolitis in very low birth weight infants

BACKGROUND

Early enteral feeding practices are potentially modifiable risk factors for necrotising enterocolitis (NEC) in very preterm or very low birth weight (VLBW) infants. Observational studies suggest that conservative feeding regimens, including slowly advancing enteral feed volumes, reduce the risk of NEC. However, it is unclear whether slow feed advancement may delay establishment of full enteral feeding, and if it could be associated with infectious morbidities secondary to prolonged exposure to parenteral nutrition.

OBJECTIVES

To determine the effects of slow rates of enteral feed advancement on the risk of NEC, mortality, and other morbidities in very preterm or VLBW infants.

SEARCH METHODS

We searched CENTRAL (2020, Issue 10), Ovid MEDLINE (1946 to October 2020), Embase via Ovid (1974 to October 2020), Maternity and Infant Care database (MIDIRS) (1971 to October 2020), CINAHL (1982 to October 2020), and clinical trials databases and reference lists of retrieved articles for eligible trials.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials that assessed effects of slow (up to 24 mL/kg/d) versus faster rates of advancement of enteral feed volumes on the risk of NEC in very preterm or VLBW infants.

DATA COLLECTION AND ANALYSIS

Two review authors separately evaluated trial risk of bias, extracted data, and synthesised effect estimates using risk ratio (RR), risk difference (RD), and mean difference. We used the GRADE approach to assess the certainty of evidence. Outcomes of interest were NEC, all-cause mortality, feed intolerance, and invasive infection.

MAIN RESULTS

We included 14 trials involving a total of 4033 infants (2804 infants participated in one large trial). None of the trials masked parents, caregivers, or investigators. Risk of bias was otherwise low. Most infants were stable very preterm or VLBW infants of birth weight appropriate for gestation. About one-third of all infants were extremely preterm or extremely low birth weight (ELBW), and about one-fifth were small for gestational age, growth-restricted, or compromised as indicated by absent or reversed end-diastolic flow velocity in the foetal umbilical artery. Trials typically defined slow advancement as daily increments of 15 to 24 mL/kg, and faster advancement as daily increments of 30 to 40 mL/kg. Meta-analyses showed that slow advancement of enteral feed volumes probably has little or no effect on the risk of NEC (RR 1.06, 95% confidence interval (CI) 0.83 to 1.37; RD 0.00, 95% CI -0.01 to 0.02; 14 trials, 4026 infants; moderate-certainty evidence) or all-cause mortality prior to hospital discharge (RR 1.13, 95% CI 0.91 to 1.39; RD 0.01, 95% CI -0.01 to 0.02; 13 trials, 3860 infants; moderate-certainty evidence). Meta-analyses suggested that slow advancement may slightly increase feed intolerance (RR 1.18, 95% CI 0.95 to 1.46; RD 0.05, 95% CI -0.02 to 0.12; 9 trials, 719 infants; low-certainty evidence) and may slightly increase the risk of invasive infection (RR 1.14, 95% CI 0.99 to 1.31; RD 0.02, 95% CI -0.00 to 0.05; 11 trials, 3583 infants; low-certainty evidence).

AUTHORS' CONCLUSIONS

The available trial data indicate that advancing enteral feed volumes slowly (daily increments up to 24 mL/kg) compared with faster rates probably does not reduce the risk of NEC, death, or feed intolerance in very preterm or VLBW infants. Advancing the volume of enteral feeds at a slow rate may slightly increase the risk of invasive infection.

Oropharyngeal administration of colostrum for preventing necrotizing enterocolitis and late-onset sepsis in preterm infants with gestational age ≤ 32 weeks: a pilot single-center randomized controlled trial

Background

Oropharyngeal administration of colostrum (OAC) may provide immunoprotective and anti-inflammatory effects that potentially reduce the incidence of necrotizing enterocolitis (NEC) and late-onset sepsis and improve short-term outcomes. Our objective was to evaluate the role of OAC in the early prevention of NEC and late-onset sepsis in preterm infants with gestational age (GA) ≤ 32 weeks.

Methods

A pilot, single-center, 1:1 parallel randomized controlled trial was conducted in a 40-bed tertiary neonatal intensive care unit (NICU) in China from 1 January 2019 to 30 September 2020. Preterm infants were randomly divided into two groups with GA ≤ 32 weeks. The OAC group included preterm infants who received 0.4 ml of maternal colostrum via the oropharyngeal route every 3 h for 10 days beginning within the first 48 h after birth, and the control group included preterm infants who received normal saline instead. Data from the two groups were collected and compared.

Results

A total of 127 infants in the OAC group and 125 infants in the control group were enrolled. The incidence of NEC (Bell stage 2 or 3) and late-onset sepsis were lower in the OAC group [2.36% vs. 10.40%, relative risk (RR) 0.23 (95% confidence interval (CI) 0.07, 0.78), adjusted RR 0.23 (95% CI 0.06, 0.84); 4.72% vs. 13.60%, RR 0.35 (95% CI 0.14, 0.85), adjusted RR 0.36 (95% CI 0.14, 0.95)]. In addition, the incidence of proven sepsis and intraventricular hemorrhage (IVH) (stage 3 or 4) were lower in the OAC group [2.36% vs. 8.80%, RR 0.27 (95% CI 0.08, 0.94); 1.57% vs. 7.20%, RR 0.22 (95% CI 0.05, 0.99)], and the time to achieve full enteral feeding was shorter (23.13 ± 9.45 days vs. 28.50 ± 14.80 days). No adverse reactions were observed in either group.

Conclusions

Oropharyngeal administration of colostrum is a safe and simple NICU procedure that may yield a potential effect in decreasing the incidences of NEC, late-onset sepsis, and severe IVH and shorten the time to achieve full enteral feeding in preterm infants with GA ≤ 32 weeks.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1900023697, Registered 8 June 2019, retrospectively registered.