Evolving understanding of neonatal necrotizing enterocolitis

Impact of postoperative necrotizing enterocolitis after neonatal cardiac surgery on neurodevelopmental outcome at 1 year of age

Objectives

We analyzed the impact of postoperative necrotizing enterocolitis (NEC) after cardiac surgery in neonatal age on neurodevelopmental (ND) outcome at 1 year of age.

Methods

Using data from the Swiss Neurodevelopmental Outcome Registry for Children with Congenital Heart Disease (ORCHID), we analyzed perioperative variables including postoperative NEC (Bell's stage ≥2) and 1-year ND outcome (Bayley III).

Results

The included patients (n = 101) had congenital heart disease (CHD), categorized as follows: 77 underwent biventricular repair for CHD with two functional chambers, 22 underwent staged palliation until the Fontan procedure for CHD with single ventricle physiology (n = 22), or 4 underwent single ventricle palliation or biventricular repair for borderline CHD (n = 4). Neonatal cardiopulmonary bypass (CBP) surgery was performed at a median age (IQR) of 8 (6) days. NEC occurred in 16 patients. Intensive care unit (ICU) length of stay (LOS) and the total duration of the hospitalization were longer in children with NEC than those in others (14 with vs. 8 days without NEC, p < 0.05; 49 with vs. 32 days without NEC, p < 0.05). The Bayley III scores of the analyzed patients determined at an age of 11.5 ± 1.5 months showed cognitive (CCS) (102.2 ± 15.0) and language scores (LCS) (93.8 ± 13.1) in the normal range and motor composite scores (MCS) (88.7 ± 15.9) in the low-normal range. After adjusting for socioeconomic status and CHD type, patients with NEC had lower CCS scores [β = -11.2 (SE 5.6), p = 0.049]. Using a cumulative risk score including NEC, we found a higher risk score to be associated with both lower CCS [β = -2.8 (SE 1.3), p = 0.030] and lower MCS [β = -3.20 (SE 1.3), p = 0.016].

Conclusions

Postoperative NEC is associated with longer ICU and hospital LOS and contributes together with other complications to impaired ND outcome at 1 year of age. In the future, national and international patient registries may provide the opportunity to analyze large cohorts and better identify the impact of modifiable perioperative risk factors on ND outcome.

Clinical Trial Registration

ClinicalTrials.gov identifier: NCT05996211.

A virtual dissemination framework to inform and evaluate a neonatal project ECHO (NeoECHO)

AIM

To present the development, implementation and evaluation of a theoretically grounded novel virtual dissemination evaluation (VDE) framework.

BACKGROUND

Care of intensive care unit patients requires access to the most up-to-date knowledge and best practices. To address this challenge, we present the development, implementation and evaluation of a theoretically grounded novel VDE framework. This framework is applied to a dissemination strategy, NeoECHO, in neonatal intensive care units. Evidence-based virtual education is implemented to prevent, detect and treat necrotizing enterocolitis in neonates.

DESIGN

Research Methodology: Discussion Paper-Methodology.

METHODS

The virtual dissemination evaluation framework is a sequential combination of Integration of Integrated-Promoting Action on Research Implementation in Health Services and Moore's Expanded Outcomes frameworks. The framework's conceptual determinants, virtual facilitators and implementation evaluations were operationalized in the NeoECHO dissemination strategy and evaluated for feasibility. The virtual dissemination evaluation framework was conceptually mapped, and operational activities were examined including theoretical constructs drawing on insights of nursing theorists, especially Fawcett's criteria (2005) for frameworks with practical application (significance, internal consistency, parsimony, testability and design fit). The NeoECHO strategy was evaluated for virtual dissemination evaluation adherence, operationalization and feasibility of implementation evaluation.

RESULTS

The virtual dissemination evaluation framework meets the criteria for a practical application and demonstrates feasibility for adherence and operationalization consistency. The implementation evaluation was usable in the virtual dissemination of best practices for neonatal care for necrotizing enterocolitis and healthcare providers were actively engaged in using NeoECHO as an implementation strategy.

CONCLUSION

This examination of the foundational aspects of the framework underscores the rigour required for generalization of practical application. Effective virtual dissemination of evidence-based practices to hospital units requires structured delivery and evaluation, enabling engaged healthcare providers to actualize education rapidly. The virtual dissemination evaluation frameworks' potential for narrowing the evidence-based practice gap in neonatal care showcases its wider significance and applicability.

IMPLICATIONS

Care of neonates in NICUs requires a multidisciplinary approach and necessitates access to the most up-to-date knowledge and best practices. More than traditional dissemination methods are required to bridge the implementation gap.

IMPACT

The effective use of the VDE framework can enhance the design, implementation and evaluation of knowledge dissemination, ultimately elevating neonatal care quality.

CLINICAL RELEVANCE

This paper introduces the VDE framework, a sequential combination of the iPARIHS and Moore's EO frameworks-as a methodological tool for designing, implementing and evaluating a neonatal strategy (NeoECHO) for virtual dissemination of education in NICUs.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Probiotic supplementation and risk of necrotizing enterocolitis and mortality among extremely preterm infants-the Probiotics in Extreme Prematurity in Scandinavia (PEPS) trial: study protocol for a multicenter, double-blinded, placebo-controlled, and registry-based randomized controlled trial

BACKGROUND

Extremely preterm infants, defined as those born before 28 weeks' gestational age, are a very vulnerable patient group at high risk for adverse outcomes, such as necrotizing enterocolitis and death. Necrotizing enterocolitis is an inflammatory gastrointestinal disease with high incidence in this cohort and has severe implications on morbidity and mortality. Previous randomized controlled trials have shown reduced incidence of necrotizing enterocolitis among older preterm infants following probiotic supplementation. However, these trials were underpowered for extremely preterm infants, rendering evidence for probiotic supplementation in this population insufficient to date.

METHODS

The Probiotics in Extreme Prematurity in Scandinavia (PEPS) trial is a multicenter, double-blinded, placebo-controlled and registry-based randomized controlled trial conducted among extremely preterm infants (n = 1620) born at six tertiary neonatal units in Sweden and four units in Denmark. Enrolled infants will be allocated to receive either probiotic supplementation with ProPrems® (Bifidobacterium infantis, Bifidobacterium lactis, and Streptococcus thermophilus) diluted in 3 mL breastmilk or placebo (0.5 g maltodextrin powder) diluted in 3 mL breastmilk per day until gestational week 34. The primary composite outcome is incidence of necrotizing enterocolitis and/or mortality. Secondary outcomes include incidence of late-onset sepsis, length of hospitalization, use of antibiotics, feeding tolerance, growth, and body composition at age of full-term and 3 months corrected age after hospital discharge.

DISCUSSION

Current recommendations for probiotic supplementation in Sweden and Denmark do not include extremely preterm infants due to lack of evidence in this population. However, this young subgroup is notably the most at risk for experiencing adverse outcomes. This trial aims to investigate the effects of probiotic supplementation on necrotizing enterocolitis, death, and other relevant outcomes to provide sufficiently powered, high-quality evidence to inform probiotic supplementation guidelines in this population. The results could have implications for clinical practice both in Sweden and Denmark and worldwide.

TRIAL REGISTRATION

( Clinicaltrials.gov ): NCT05604846.

Evaluation of the protective and therapeutic effects of extra virgin olive oil rich in phenol in experimental model of neonatal necrotizing enterocolitis by clinical disease score, ınflammation, apoptosis, and oxidative stress markers

BACKGROUND AND AIM

Necrotizing Enterocolitis (NEC) is an inflammation-associated ischemic necrosis of the intestine. To investigate the effects of extra virgin olive oil (EVOO) on inflammation, oxidative stress, apoptosis, and histological changes in NEC-induced newborn rats.

MATERIALS AND METHODS

24 rats were randomly divided into three groups: control, NEC and NEC + EVOO. NEC induction was performed using hypoxia-hyperoxia, formula feeding, and cold stress. The NEC + EVOO group received 2 ml/kg EVOO with high phenolic content by gavage twice a day for 3 days. 3 cm of bowel including terminal ileum, cecum, and proximal colon was excised.

RESULTS

Weight gain and clinical disease scores were significantly higher in the NEC + EVOO group than in the NEC group (p < 0.001). EVOO treatment caused significant decreases in IL1β, IL6 levels (p = 0.016, p = 0.029 respectively) and EGF, MDA levels (p = 0.032, p = 0.013 respectively) compared to NEC group. Significant decreases were observed in IL6 gene expression in the NEC + EVOO group compared to the NEC group (p = 0.002). In the group NEC + EVOO, the number of Caspase-3 positive cells was found to be significantly reduced (p < 0.001) and histopathological examination revealed minimal changes and significantly lower histopathological scores (p < 0.001).

CONCLUSION

Phenol-rich EVOO prevents intestinal damage caused by NEC by inhibiting inflammation, oxidative stress, apoptosis.

Can Postbiotics Represent a New Strategy for NEC?

Intestinal bacteria, also known as gut microbiota, are a rich ecology of microorganisms found in the human digestive tract. Extensive study has highlighted their critical relevance in preserving human health. New research has revealed that bacterial viability is not invariably necessary to induce health benefits. Postbiotics (defined soluble substances produced as a byproduct of the metabolic processes of living microbes) have thus emerged as an important topic of research. They contribute to shaping the gut microbiota, exert immune-modulation activity, and improve the integrity of the gut barrier.Alterations in preterm gut colonization associated with intestinal barrier immaturity and the increased reactivity of the intestinal mucosa to colonizing bacteria have been implicated in the pathogenesis of necrotizing enterocolitis. Postbiotics have shown promising outcomes in reducing the risk of developing NEC, lowering inflammation, encouraging the development of good bacteria, and strengthening the intestinal barrier. This is an important advancement in newborn care and highlights the potential of postbiotics to avoid severe intestinal disorders.

Inhaled Nitric Oxide and Higher Necrotizing Enterocolitis Rates in Congenital Heart Disease Patients

INTRODUCTION

Certain congenital cardiac lesions are at increased risk for the development of necrotizing enterocolitis (NEC). These patients are often reliant on pulmonary and systemic vasomodulators to maintain adequate perfusion and oxygenation. This study sought to determine whether pulmonary or systemic vasodilator treatment is protective against the development of NEC in this population.

METHODS

We utilized International Classification of Diseases (ICD) codes to identify high risk congenital cardiac disease patients ≤6 mo of age, cared for at a tertiary children's hospital between January 2011 and January 2021. Cardiac anomalies were stratified into ductal dependent (pulmonary DD-P or systemic DD-S) or independent lesions. The rate of NEC development in those who received vasodilators (inhaled nitric oxide [iNO], pulmonary vasodilators, systemic vasodilators) was compared to controls in a multivariate analysis.

RESULTS

Of the 352 patients, who met inclusion criteria, 77.6% had ductal dependent lesions (DD-S 41.9%, DD-P 35.7%), 19.5% received iNO, and 37.5% received other vasodilatory drugs. The overall NEC rate was 15.1%. On univariate analysis, DD-S, iNO use, and systemic vasodilators was associated with a significantly higher risk of NEC, while DD-P was associated with lower NEC risk. On multivariate analysis, only iNO (odds ratio 2.725, confidence interval [1.36-5.44]) and DD-S (odds ratio 2.279, confidence interval [1.02-5.11]) were independent risk factors for NEC.

CONCLUSIONS

In patients with at-risk congenital cardiac disease lesions, a ductus dependent systemic circulation or iNO treatment is associated with an increased risk of developing NEC. The presence of iNO or DD-S should be utilized as markers of increased risk both in the prevention and workup of suspected NEC.

Selective targeting of MD2 attenuates intestinal inflammation and prevents neonatal necrotizing enterocolitis by suppressing TLR4 signaling

Neonatal necrotizing enterocolitis (NEC) is an inflammatory disease that occurs in premature infants and has a high mortality rate; however, the mechanisms behind this disease remain unclear. The TLR4 signaling pathway in intestinal epithelial cells, mediated by TLR4, is important for the activation of the inflammatory storm in NEC infants. Myeloid differentiation protein 2 (MD2) is a key auxiliary component of the TLR4 signaling pathway. In this study, MD2 was found to be significantly increased in intestinal tissues of NEC patients at the acute stage. We further confirmed that MD2 was upregulated in NEC rats. MD2 inhibitor (MI) pretreatment reduced the occurrence and severity of NEC in neonatal rats, inhibited the activation of NF-κB and the release of inflammatory molecules (TNF-α and IL-6), and reduced the severity of intestinal injury. MI pretreatment significantly reduced enterocyte apoptosis while also maintaining tight junction proteins, including occludin and claudin-1, and protecting intestinal mucosal permeability in NEC rats. In addition, an NEC in vitro model was established by stimulating IEC-6 enterocytes with LPS. MD2 overexpression in IEC-6 enterocytes significantly activated NF-κB. Further, both MD2 silencing and MI pretreatment inhibited the inflammatory response. Overexpression of MD2 increased damage to the IEC-6 monolayer cell barrier, while both MD2 silencing and MI pretreatment played a protective role. In conclusion, MD2 triggers an inflammatory response through the TLR4 signaling pathway, leading to intestinal mucosal injury in NEC. In addition, MI alleviates inflammation and reduces intestinal mucosal injury caused by the inflammatory response by blocking the TLR4-MD2/NF-κB signaling axis. These results suggest that inhibiting MD2 may be an important way to prevent NEC.

Abnormalities in microbial composition and function in infants with necrotizing enterocolitis: A single-center observational study

OBJECTIVE

To investigate the features and functions of the intestinal microbiota in neonates with necrotizing enterocolitis (NEC) in a single center in China.

METHODS

We collected clinical information and stool samples from 19 participants in our center, including 9 infants with necrotizing enterocolitis and 10 control infants. DNA was extracted from the samples, and 16S rRNA gene sequencing was used to analyse the participants' gut microbiota. Functional prediction was achieved using PICRUSt2.

RESULTS

Alpha diversity analysis found that similar levels of bacterial richness and diversity were found in the gut microbiota of infants with NEC and control infants (P = 0.1800), whereas beta diversity analysis suggested that the overall structures of the gut microbiota were significantly different (P = 0.0020). The Mann-Whitney U test of bacterial composition and abundance analysis revealed that the abundance levels of Proteobacteria (P = 0.03049) and Firmicutes (P = 0.01011) significantly differed between the two groups at the phylum level. Proteobacteria was the most abundant phylum in the NEC group. At the genus level, the abundance levels of Enterococcus (P = 0.0003), Streptococcaceae (P = 0.0109) and Lactobacillales (P = 0.0171) were significantly decreased in infants with NEC. Furthermore, the linear discriminant analysis effect size (LEfSe) method showed 12 bacterial taxa with significant differences in relative abundances in the two groups. Interestingly, members of Proteobacteria were enriched in NEC samples. In addition, functional prediction suggested that the microbial changes observed in infants with NEC resulted in a decline in galactose metabolism, the pentose phosphate pathway, fructose and mannose metabolism, amino sugar and nucleotide sugar metabolism, glycolysis/gluconeogenesis, starch and sucrose metabolism, and phosphotransferase system (PTS) pathways (P < 0.05).

CONCLUSIONS

Our study shows the compositional and functional alterations of the intestinal microbiota in NEC, which will help demonstrate the relationship between the gut microbiota and NEC pathogenesis.

Lack of Enteral Feeding Associated with Mortality in Prematurity and Necrotizing Enterocolitis

BACKGROUND

Necrotizing Enterocolitis (NEC) remains a significant cause of morbidity and mortality. Recently, there has been an increased recognition of the importance of intestinal immunity and the associations with antibiotics and enteral feeds in the pathophysiology of NEC. The primary purpose of this study is to examine the association of enteral feeds on the survival of premature neonates with NEC.

MATERIAL AND METHODS

A retrospective review using the Vermont Oxford Network for a Level IV NICU from January 1, 2013 through December 31, 2019 was performed. All neonates had a gestational age between 22 to 29 weeks, weighed at least 300 grams (n = 653), had a reported enteral feed status and were treated for NEC (n = 43). Data analysis utilized two-tailed t-tests for NEC and infection rates then Fisher's exact tests for survival status.

RESULTS

The incidence of NEC in the population was 6.6% (43/653). Of the 43 neonates treated for NEC, 27 were enterally fed, while the other 16 were not. All 27 neonates with NEC that were able to achieve enteral feeds survived and had an infection rate of 22.2%. Meanwhile, all 16 neonates with NEC that were unable to achieve enteral feeds died and had an infection rate of 62.5%.

CONCLUSIONS

There is a significant association between enteral feeds and NEC, survival, and infection rates in premature neonates. These findings support the importance of intestinal immunity and the microbiota in NEC. Given the limitations of the retrospective review, the profound survival advantage with enteral feeds reinforces the need for further study.

Exogenous Autoinducer-2 Rescues Intestinal Dysbiosis and Intestinal Inflammation in a Neonatal Mouse Necrotizing Enterocolitis Model

Autoinducer-2 (AI-2) is believed to be a bacterial interspecies signaling molecule that plays an important role in the regulation of the physiological behaviors of bacteria. The effect of AI-2 on the process of necrotizing enterocolitis (NEC) is unknown, and the aim of this study was to study the effect of AI-2 in a mouse NEC model. C57BL/6 mouse pups were randomly divided into three groups: the control group, the NEC group, and the NEC+AI-2 (NA) group. Exogenous AI-2 (500 nM) was added to the formula milk of the NA group. The concentrations of fecal AI-2 and flora were tested. The expression of cytokines, TLR4 and NF-κB in intestinal tissue was detected. The AI-2 level was significantly decreased in the NEC group (P<0.05). Compared with the NEC group, the intestinal injury scores, expression of TLR4, NF-kB, and proinflammatory factors (IL-1β, IL-6, IL-8 and TNF-α) were reduced, and expression of anti-inflammatory factor (IL-10) was increased in the NA group mice (P<0.05). At the phylum level, the Proteobacteria abundance in the NA group was significantly increased, while the Bacteroidota abundance in the control group was significantly increased (P<0.05). At the genus level, Helicobacter and Clostridium_sensu_stricto_1 exhibited significantly greater abundance in the NEC group than in the other two groups, while Lactobacillus had the opposite trend (P<0.05). In addition, the abundances of Klebsiella, Rodentibacter and Enterococcus were significantly higher in the NA group than in the NEC and control groups (P < 0.05). Exogenous AI-2 partially reverses flora disorder and decreases inflammation in an NEC mouse model.

Effect and Safety of Saccharomyces boulardii for Neonatal Necrotizing Enterocolitis in Pre-term Infants: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

Necrotizing enterocolitis (NEC) is one of the most common and urgent neonatal emergencies in the neonatal intensive care unit. This disease leads to considerable morbidity and mortality; it also imposes a huge financial burden on patient family and society. Thus, Treatment and prevention of NEC are crucial. This meta-analysis aims to investigate the effect and safety of Saccharomyces boulardii for NEC in pre-term infants.

METHODS

A comprehensive search was retrieved in six major databases. The search included randomized controlled trials (RCTs) reporting the incidence of NEC (stage ≥ II), sepsis, mortality, feeding intolerance, full feeding days, time to regain birth weight, days of hospitalization and adverse effects. The random model was used to calculate risk ratio (RR), the standard mean difference (SMD) and its 95% confidence interval (95% CI) between the S. boulardii group and control group. Statistical analyses were conducted using Cochrane systematic review software, Rev Man (version 5.3).

RESULTS

In total, 10 RCTs involving 1264 participants met the inclusion criteria. There were significant reductions in the incidence of NEC [RR = 0.56, 95% CI (0.36-0.89)], feeding intolerance [RR = 0.52, 95% CI (0.39-0.68)], full feeding days [SMD = -1.25, 95% CI (-2.06 to -0.45)] and hospitalization days [SMD = -1.33, 95% CI (-2.64 to -0.02)] in the study group compared with the control group. However, there were no significant differences in sepsis [RR = 0.84, 95% CI (0.61-1.17)], death [RR = 1.12, 95% CI (0.46-2.70)] and the time to regain birth weight [SMD = -0.93, 95% CI (-1.88 to 0.03)] between the two groups. The adverse effect of S. boulardii was not reported. The overall methodological quality was evaluated as moderate by the Cochrane Bias Risk Assessment Tool.

CONCLUSION

According to this evidence we recommend S. boulardii to prevent NEC, reduce the feeding intolerance, shorten the full feeding days and hospitalization days. However, S. boulardii might be invalid on the incidence of sepsis, mortality and the time to regain birth weight.

REGISTRATION

This review has been registered to the PROSPERO (International prospective register of systematic reviews) on 5 December 2019 (ID: CRD42019147896).

Osmolality of Commonly Used Oral Medications in the Neonatal Intensive Care Unit

OBJECTIVE

The administration of hyperosmolar oral products in neonates has been associated with gastrointestinal complications. The American Academy of Pediatrics recommends a maximum osmolality of 450 mOsm/kg for formulas and enteral nutrition for term infants, and recent studies reported intolerance to enteral nutrition with osmolality above 500 mOsm/kg in low birthweight infants. The osmolality of medications administered to neonates is often not available in the literature or from manufacturers. The purpose of this study was to determine the osmolality of oral medications commonly administered to neonates in the NICU.

METHODS

Fifty-two oral medications were chosen for this study, including solutions, suspensions, syrups, elixirs, and intravenous solutions administered orally. The osmolality of each medication was measured in triplicate by using freezing point depression.

RESULTS

Thirty-seven of the 43 medications with measurable values (86.1%) had an osmolality greater than 500 mOsm/kg, and 6 medications (14%) had an osmolality less than 500 mOsm/kg. Nine medications did not result in a value.

CONCLUSIONS

Our study provides osmolality data on oral medications commonly used in neonates with most oral medications having an osmolality greater than 500 mOsm/kg.

Impact and Clinical Implications of Prematurity on Adaptive Immune Development

Purpose of Review

Detail normal adaptive immune maturation during fetal and neonatal life and review the clinical implications of arrested immune development.

Recent Findings

Advancements in the field of immunology have enabled investigations of the adaptive immunity starting during fetal life. New insights have drawn important distinctions between the neonatal and adult immune systems. The presence of diverse immunologic responses in the perinatal period suggests the importance of in utero immune development. Disruption of immune maturation due to premature birth may have significant implications for clinical pathology.

Summary

Establishing protective adaptive immunity during the perinatal period is critical for effective immune responses later in life. Preterm infants are susceptible to aberrant immune system maturation and inflammatory immune responses have been associated with the development of necrotizing enterocolitis (NEC) and bronchopulmonary dysplasia (BPD). Improving our understanding of how immune responses contribute to the pathogenesis of NEC and BPD may offer new opportunities for future treatment and prevention of these diseases.

Protective effects of different doses of human milk on neonatal necrotizing enterocolitis

We aim to summarize the evidence focusing on the effects of various doses of human milk on the risk of neonatal necrotizing enterocolitis (NEC). The eligible articles in the study were those investigating the association between human milk and NEC published before June 26, 2019, in the PubMed, EMBASE, the Cochrane Library, VIP database, CNKI database, and Wangfang database. The included criteria were as follows: premature infants of <37 weeks; randomly controlled trials (RCTs); those fed by mother's own milk or donor human milk; studies focused on the comparison of human milk and formula milk, involving various breast milk doses; and NEC-related studies. Compared with the exclusive formula, the incidence of NEC in the infants fed by exclusive human milk was significantly lower. The incidence of NEC in the infants fed by exclusive human milk was significantly lower than that of partial human milk [risk ratio (RR) = 0.54, 95% confidence interval (95% CI): 0.36-0.79, P < .05]. The incidence of NEC in the infants fed mainly by human milk was significantly lower than that of mainly fed by formula. Incidence of NEC in the infants fed by exclusive human milk was significantly lower than that of any formula (RR = 0.49, 95% CI: 0.34-0.71, P < .05). In summary, this meta-analysis was based on the RCTs involving the prevention of NEC using human milk. Exclusive human milk and partial human milk reduced the incidence of NEC in premature infants, especially in the those fed by high proportion of human milk. In addition, more RCTs are needed to further validate such conclusion.

Does probiotic bacteremia in premature infants impact clinically relevant outcomes? A case report and updated review of literature

Prophylactic use of probiotics decreases the incidence of necrotizing enterocolitis (NEC) in premature infants. However, there are ongoing concerns related to the routine use of probiotics including inconsistent literature regarding optimal dose and strain, lack of regulatory standards in production and reports regarding potential side effects. There is limited data regarding the incidence of probiotic bacteremia and its impact on relevant clinical outcomes in the premature population. We report the first case of Bifidobacterium longum bacteremia in our center since the routine introduction of probiotics. The neonate had NEC with perforation on day of life 7, which likely led to translocation of the probiotic strain to the blood stream. The neonate did not have any hemodynamic instability and the repeat blood culture was negative after starting antibiotic therapy. We also conducted a literature review and found 13 other cases of probiotic bacteremia in premature or very low birth weight neonates. Although the incidence of probiotic bacteremia is low, it can impact several clinical outcomes including prolonged exposure to antibiotics, removal of central lines and additional laboratory testing such as lumbar puncture. There has been no mortality attributable to probiotic bacteremia and there is no data regarding long term neurodevelopmental outcomes.

Maltodextrin-induced intestinal injury in a neonatal mouse model

Prematurity and enteral feedings are major risk factors for intestinal injury leading to necrotizing enterocolitis (NEC). An immature digestive system can lead to maldigestion of macronutrients and increased vulnerability to intestinal injury. The aim of this study was to test in neonatal mice the effect of maltodextrin, a complex carbohydrate, on the risk of intestinal injury. The goal was to develop a robust and highly reproducible murine model of intestinal injury that allows insight into the pathogenesis and therapeutic interventions of nutrient-driven intestinal injury. Five- to 6-day-old C57BL/6 mice were assigned to the following groups: dam fed (D); D+hypoxia+Klebsiella pneumoniae; maltodextrin-dominant human infant formula (M) only; M+hypoxia; and M+hypoxia+K. pneumoniae. The mice in all M groups were gavage fed five times a day for 4 days. Mice were exposed to hypoxia twice a day for 10 min prior to the first and last feedings, and K. pneumoniae was added to feedings as per group assignment. Mice in all M groups demonstrated reduced body weight, increased small intestinal dilatation and increased intestinal injury scores. Maltodextrin-dominant infant formula with hypoxia led to intestinal injury in neonatal mice accompanied by loss of villi, increased MUC2 production, altered expression of tight junction proteins, enhanced intestinal permeability, increased cell death and higher levels of intestinal inflammatory mediators. This robust and highly reproducible model allows for further interrogation of the effects of nutrients on pathogenic factors leading to intestinal injury and NEC in preterm infants.This article has an associated First Person interview with the first author of the paper.

Opportunities for the federal government to advance necrotizing enterocolitis research

BACKGROUND

Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality in the neonatal ICU with minimal progress in the research.

METHODS

Federal webpages were queried to look for funding opportunity announcements (FOAs) and to develop lists of funded projects on NEC to identify gaps in NEC-related research topics.

RESULTS

Over the past 30 years, the National Institutes of Health (NIH) issued two FOAs to stimulate research on NEC with $4.1 million set aside for the first year of respective funding. We identified 23 recently funded studies of which 18 were research projects, 4 training grants, and 1 conference grant support. Only one grant focused on parent and family engagement in the NICU.

CONCLUSION

There are significant research gaps that can be addressed with adequate funding from the federal government on the prevention and treatment of NEC.

Developmental 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure of either parent enhances the risk of necrotizing enterocolitis in neonatal mice

BACKGROUND

Necrotizing enterocolitis (NEC) is a rare, but potentially fatal intestinal inflammatory condition most often arising in premature infants. Infants provided formula are also at greater risk of developing this disease. Although the majority of formula-fed, preterm infants do not develop NEC, up to 30% of infants with the disease do not survive. Thus, identifying additional, currently unrecognized factors, which may predispose a specific infant to NEC development would be a significant clinical advancement. In this regard, we have previously reported that offspring of female or male mice with a history of developmental exposure to the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exhibit altered sensitivity to inflammatory challenges and are frequently born premature. Herein, we examined the possibility that, compared to unexposed mice (F1_NONE ), developmental TCDD exposure of either parent (maternal, F1M_TCDD , or paternal, F1P_TCDD ) would enhance the risk of NEC in offspring (F2_TCDD mice) in association with supplemental formula feeding.

METHODS

Beginning on postnatal day 7, all neonates were randomized to maternal milk only or maternal milk with up to 20 supplemental formula feedings. All pups remained with the Dams and were additionally allowed to nurse ad libitum.

RESULTS

Formula-fed F2_NONE pups rarely developed NEC while this disease was common in formula-fed F2M_TCDD and F2P_TCDD mice. Unexpectedly, 50% of F2M_TCDD pups that were not provided supplemental formula also developed NEC.

CONCLUSIONS

Our studies provide evidence that a history of parental TCDD exposure enhances the risk of NEC in offspring and suggest exposure to environmental immunotoxicants such as TCDD may also contribute to this inflammatory disease in humans.

TMEM16A deficiency: a potentially fatal neonatal disease resulting from impaired chloride currents

INTRODUCTION

TMEM16A is a calcium-activated chloride channel expressed in various secretory epithelia. Two siblings presented in early infancy with reduced intestinal peristalsis and recurrent episodes of haemorrhagic diarrhoea. In one of them, the episodes were characterised by hepatic pneumatosis with gas bubbles in the portal vein similar to necrotising enterocolitis of the newborn.

METHODS

Exome sequencing identified a homozygous truncating pathogenic variant in ANO1. Expression analysis was performed using reverse transcription PCR, western blot and immunohistochemistry. Electrophysiological and cell biological studies were employed to characterise the effects on ion transport both in patient respiratory epithelial cells and in transfected HEK293 cells.

RESULTS

The identified variant led to TMEM16A dysfunction, which resulted in abolished calcium-activated Cl^- currents. Secondarily, CFTR function is affected due to the close interplay between both channels without inducing cystic fibrosis (CF).

CONCLUSION

TMEM16A deficiency is a potentially fatal disorder caused by abolished calcium-activated Cl^- currents in secretory epithelia. Secondary impairment of CFTR function did not cause a CF phenotyp, which may have implications for CF treatment.

Probiotics and Preterm Infants: A Position Paper by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Committee on Nutrition and the European Society for Paediatric Gastroenterology Hepatology and Nutrition Working Group for Probiotics and Prebiotics

More than 10,000 preterm infants have participated in randomised controlled trials on probiotics worldwide, suggesting that probiotics in general could reduce rates of necrotising enterocolitis (NEC), sepsis, and mortality. Answers to relevant clinical questions as to which strain to use, at what dosage, and how long to supplement are, however, not available. On the other hand, an increasing number of commercial products containing probiotics are available from sometimes suboptimal quality. Also, a large number of units around the world are routinely offering probiotic supplementation as the standard of care despite lacking solid evidence. Our recent network meta-analysis identified probiotic strains with greatest efficacy regarding relevant clinical outcomes for preterm neonates. Efficacy in reducing mortality and morbidity was found for only a minority of the studied strains or combinations. In the present position paper, we aim to provide advice, which specific strains might potentially be used and which strains should not be used. In addition, we aim to address safety issues of probiotic supplementation to preterm infants, who have reduced immunological capacities and occasional indwelling catheters. For example, quality reassurance of the probiotic product is essential, probiotic strains should be devoid of transferable antibiotic resistance genes, and local microbiologists should be able to routinely detect probiotic sepsis. Provided all safety issues are met, there is currently a conditional recommendation (with low certainty of evidence) to provide either Lactobacillus rhamnosus GG ATCC53103 or the combination of Bifidobacterium infantis Bb-02, Bifidobacterium lactis Bb-12, and Streptococcus thermophilus TH-4 in order to reduce NEC rates.

Recent Advances in Prevention and Therapies for Clinical or Experimental Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is one of the most severe diseases of preterm neonates and has a high mortality rate. With the development of inspection techniques and new biomarkers, the diagnostic accuracy of NEC is constantly improving. The most recognized potential risk factors include prematurity, formula-feeding, infection, and microbial dysbiosis. With further understanding of the pathogenesis, more effective prevention and therapies will be applied to clinical or experimental NEC. At present, such new potential prevention and therapies for NEC are mainly focused on the Toll-like receptor 4 inflammatory signaling pathway, the repair of intestinal barrier function, probiotics, antioxidative stress, breast-feeding, and immunomodulatory agents. Many new studies have changed our understanding of the pathogenesis of NEC and improve our approaches for preventing and treating of NEC each year. This review provides an overview of the recent researches focused on clinical or experimental NEC and highlights the advances made within the past 5 years toward the development of new potential preventive approaches and therapies for this disease.

Arguments against routine administration of probiotics for NEC prevention

PURPOSE OF REVIEW

Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality among premature neonates. Although randomized trials have shown that probiotics may be efficacious in the prevention of NEC, their use has not been universally adopted in the neonatal intensive care unit (NICU). Caveats regarding routine probiotic supplementation for the prevention of NEC are summarized in this review.

RECENT FINDINGS

Accumulating evidence indicates that prophylactic probiotic supplementation in preterm infants can reduce the incidence of NEC. However, substantial knowledge gaps, regulatory issues, and implementation challenges should be addressed before probiotics are introduced as standard of care for all preterm neonates. Limitations of published trial data have made it challenging to define regimens that optimize efficacy and safety in specific patient subgroups. Moreover, the current probiotic market lacks rigorous regulatory oversight, which could raise concerns about the quality and safety of probiotic products. Finally, implementation pitfalls include risks of cross-colonization and resource requirements to monitor and mitigate potential adverse events.

SUMMARY

Probiotics have shown promise in the prevention of NEC. However, there is insufficient evidence to guide the selection of optimal regimens. Furthermore, issues related to regulatory and institutional oversight should be addressed before supplementation is routinely implemented in NICUs.