Contemporary Outcomes for Infants with Necrotizing Enterocolitis-A Systematic Review

Applications of Artificial Intelligence in Acute Abdominal Imaging

Artificial intelligence (AI) is a rapidly growing field with significant implications for radiology. Acute abdominal pain is a common clinical presentation that can range from benign conditions to life-threatening emergencies. The critical nature of these situations renders emergent abdominal imaging an ideal candidate for AI applications. CT, radiographs, and ultrasound are the most common modalities for imaging evaluation of these patients. For each modality, numerous studies have assessed the performance of AI models for detecting common pathologies, such as appendicitis, bowel obstruction, and cholecystitis. The capabilities of these models range from simple classification to detailed severity assessment. This narrative review explores the evolution, trends, and challenges in AI applications for evaluating acute abdominal pathologies. We review implementations of AI for non-traumatic and traumatic abdominal pathologies, with discussion of potential clinical impact, challenges, and future directions for the technology.

Assessing the association between necrotizing enterocolitis and the type of initial central venous access in preterm infants

AIM

Umbilical venous catheters (UVC) have been associated with an increased risk of necrotizing enterocolitis (NEC). We aimed to assess the relationship between the type of initial central venous access in preterm infants and NEC.

METHODS

Using the Canadian Neonatal Network database, we identified preterm infants <30 weeks gestation born between 2014 and 2021 in one of 32 participating centres who had a peripherally inserted central catheter (PICC) as initial vascular access. These infants were matched in a 1:1 ratio based on gestational age, sex and birth weight to infants in two other groups: (i) those who initially had an UVC and (ii) those who had an UVC followed by a PICC.

RESULTS

A total of 497 infants were included in this study: 165 in the PICC group, 164 in the UVC group and 165 in the UVC + PICC group. There was no association between the type of initial central venous access and NEC.

CONCLUSION

Although this retrospective study did not find an association between the type of initial central venous access and NEC, larger prospective studies are required to evaluate this association.

CSF1 is expressed by the intestinal epithelial cells to regulate Mφ macrophages and maintain epithelial homeostasis and is downregulated in neonates with necrotizing enterocolitis

BACKGROUND

Colony stimulating factor 1 (CSF1) is generally expressed by immune cells in response to pro-inflammatory stimuli. The CSF1 receptor (CSFR) is activated by CSF1, and plays a key role in macrophage homeostasis. Furthermore, the CSF1R+ macrophages maintain homeostasis in the intestinal epithelium. The aim of this study was to explore the functions of CSF1-expressing and CSF1R+ macrophages in necrotizing enterocolitis (NEC), which commonly affects the ileum of neonates.

METHODS

In-situ CSF1 expression in the intestines of neonates with NEC or intestinal atresia (n = 4 each) was detected by immunofluorescence staining. The CSF1 levels in the intestinal crypt-derived organoid cultures were measured by ELISA. Peripheral blood monocyte-derived Mφ macrophages were co-cultured with the organoids and stimulated with lipopolysaccharide (LPS) to mimic the inflamed state of the ileum in NEC patients.

RESULTS

CSF1 was expressed in the intestinal epithelial cells of the fetal and neonatal samples, but suppressed in the NEC samples. Furthermore, CSF1 expression was downregulated in the intestinal crypt-derived organoids by LPS. CSF1R+ macrophages were detected near the intestinal crypts in the non-inflamed intestines but were absent in tissues obtained from pediatric NEC patients. Peripheral blood monocyte-derived macrophages promoted intestinal organoid proliferation in vitro following CSF1 stimulation. Finally, low concentrations of LPS slightly enhanced the proliferation of organoids co-cultured with the macrophages, whereas higher doses had a significant inhibitory effect.

CONCLUSIONS

Intestinal epithelial cells express CSF1 to regulate the resident macrophages, maintain epithelial homeostasis, and resist infection. The abundant CSF1R+ macrophages in the fetal intestine may overexpress TNF-α upon activation of the TLR4/NF-κB pathway, resulting in epithelial damage and NEC induction.

Non-nutritional use of human milk as a therapeutic agent in neonates: Brain, gut, and immunologic targets

Human milk (HM) exposure improves short- and long-term outcomes for infants due to a complex milieu of bioactive, stem cell, anti-inflammatory, anti-microbial, and nutritive components. Given this remarkable biologic fluid, non-nutritional utilization of HM as a targeted therapeutic is being explored in pre-clinical and clinical studies. This article describes recent research pertinent to non-nutritional uses of HM for neurologic, gastrointestinal, and infectious pathologies in neonates, as well as future directions.

Surgery for intestinal injuries in very preterm infants: a Norwegian population-based study with a new approach to disease classification

OBJECTIVE

To evaluate population-based data on very preterm infants (<32 weeks gestation) operated for intestinal injuries, focusing on necrotising enterocolitis (NEC) and focal intestinal perforation (FIP).

DESIGN

Nationwide, population-based registry cohort study.

SETTING

All 21 neonatal units in Norway.

PARTICIPANTS

All very preterm infants born from 2014 through 2021 and admitted to a neonatal unit.

MAIN OUTCOME MEASURES

Incidence of surgery for subgroups of intestinal injuries, medical record data on laboratory-radiology results, anatomical location of affected bowel, length of resections, number of re-operations, morbidities of prematurity and/or death before discharge.

RESULTS

Abdominal surgery was performed in 124/4009 (3.1%) very preterm infants and in 97/1300 (7.5%) extremely preterm infants <28 weeks. The main intestinal injuries operated were NEC (85/124; 69%), FIP (26/124; 21%) and 'other abdominal pathologies' (13/124; 10%). NEC cases were divided in (i) acute NEC, extensive disease (n=18), (ii) non-extensive disease (n=53) and (iii) NEC with surgery >3 days after disease onset (n=14). High lactate values immediately prior to surgery was predominantly seen in acute NEC-extensive disease and associated with high mortality. Other laboratory values could not discriminate between acute NEC and FIP. Timing of surgery for acute NEC and FIP overlapped. Radiological absence of portal venous gas was typical in FIP. Most infants (62.5%) underwent a stoma formation at initial surgery. The overall survival rate was 67% for NEC and 77% for FIP.

CONCLUSION

NEC cases have different presentation and prognosis depending on the extent of bowel affected. Revised classifications for intestinal injuries in preterm infants may improve prognostication and better guide therapy.

Exogenous autoinducer-2 alleviates intestinal damage in necrotizing enterocolitis via PAR2/MMP3 signaling pathway

BACKGROUND

Imbalanced intestinal microbiota and damage to the intestinal barrier contribute to the development of necrotizing enterocolitis (NEC). Autoinducer-2 (AI-2) plays a crucial role in repairing intestinal damage and reducing inflammation.

OBJECTIVE

This study aimed to investigate the impact of AI-2 on the expression of intestinal zonula occludens-1 (ZO-1) and occludin proteins in NEC. We evaluated its effects in vivo using NEC mice and in vitro using lipopolysaccharide (LPS)-stimulated intestinal cells.

METHODS

Pathological changes in the intestines of neonatal mice were assessed using histological staining and scoring. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay to determine the optimal conditions for LPS and AI-2 interventions. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to analyze the mRNA levels of matrix metalloproteinase-3 (MMP3), protease activated receptor-2 (PAR2), interleukin-1β (IL-1β), and IL-6. Protein levels of MMP3, PAR2, ZO-1, and occludin were evaluated using western blot, immunohistochemistry, or immunofluorescence.

RESULTS

AI-2 alleviated NEC-induced intestinal damage (P < 0.05) and enhanced the proliferation of damaged IEC-6 cells (P < 0.05). AI-2 intervention reduced the mRNA and protein expressions of MMP3 and PAR2 in intestinal tissue and cells (P < 0.05). Additionally, it increased the protein levels of ZO-1 and occludin (P < 0.05), while reducing IL-1β and IL-6 mRNA expression (P < 0.05).

CONCLUSION

AI-2 intervention enhances the expression of tight junction proteins (ZO-1 and occludin), mitigates intestinal damage in NEC neonatal mice and IEC-6 cells, potentially by modulating PAR2 and MMP3 signaling. AI-2 holds promise as a protective intervention for NEC. AI-2 plays a crucial role in repairing intestinal damage and reducing inflammation.

Redox Chemistry: Implications for Necrotizing Enterocolitis

Reduction-oxidation (redox) chemistry plays a vital role in human homeostasis. These reactions play critical roles in energy generation, as part of innate immunity, and in the generation of secondary messengers with various functions such as cell cycle progression or the release of neurotransmitters. Despite this cornerstone role, if left unchecked, the body can overproduce reactive oxygen species (ROS) or reactive nitrogen species (RNS). When these overwhelm endogenous antioxidant systems, oxidative stress (OS) occurs. In neonates, OS has been associated with retinopathy of prematurity (ROP), leukomalacia, and bronchopulmonary dysplasia (BPD). Given its broad spectrum of effects, research has started to examine whether OS plays a role in necrotizing enterocolitis (NEC). In this paper, we will discuss the basics of redox chemistry and how the human body keeps these in check. We will then discuss what happens when these go awry, focusing mostly on NEC in neonates.

Necrotising enterocolitis in a middle-income country: Early onset and risk factors for mortality

AIM

There is limited literature available about necrotising enterocolitis (NEC) in low- and middle-income countries. This study sought to determine the proportion, pattern and risk factors for mortality among very low birth weight (VLBW) neonates with NEC in a middle-income setting.

METHODS

A retrospective observational cohort study was conducted on all infants with birth weights less than 1501 g admitted from 2018 to 2020 at Groote Schuur Hospital, Cape Town, South Africa. Data were obtained from the Vermont Oxford Network and hospital folders.

RESULTS

A total of 104/1582 (6.6%) neonates were diagnosed with NEC with a median onset of 8 days of life. The mortality rate was 39.0%, compared to the all-cause mortality rate of 18.7% for VLBW neonates. Thirty-two (32.0%) neonates with NEC were transferred for surgery of whom 10 (31.3%) died. Small for gestational age (p = 0.13), NEC stage 2B or above (p = 0,002), a positive blood culture (p = 0.018), a raised C-reactive protein (p = 0.013), hyponatraemia (p = 0.004), anaemia requiring blood transfusion (p = 0.003) and thrombocytopenia requiring platelet transfusion (p = 0.033) were associated with mortality. A positive blood culture was found in 37.0% with a predominance of Klebsiella pneumoniae isolates.

CONCLUSION

NEC has an early onset and a high mortality rate in our setting.

Macrophage α7nAChR alleviates the inflammation of neonatal necrotizing enterocolitis through mTOR/NLRP3/IL-1β pathway

BACKGROUND

Neonatal necrotizing enterocolitis (NEC) is one of the most prevalent and severe intestinal emergencies in newborns. The inflammatory activation of macrophages is associated with the intestinal injury of NEC. The neuroimmune regulation mediated by α7 nicotinic acetylcholine receptor (α7nAChR) plays an important role in regulating macrophage activation and inflammation progression, but in NEC remains unclear. This study aims to explore the effect of macrophage α7nAChR on NEC.

METHODS

Mice NEC model were conducted with high-osmolarity formula feeding, hypoxia, and cold stimulation. The α7nAChR agonist PNU-282987 and mTOR inhibitor rapamycin were treated by intraperitoneal injections in mice. The expression and distribution of macrophages, α7nAChR, and phospho-mammalian target of rapamycin (p-mTOR) in the intestines of NEC patients and mice was assessed using immunohistochemistry, immunofluorescence, and flow cytometry. The expression of NLRP3, activated caspase-1 and IL-1β in mice intestines was detected by flow cytometry, western blot or ELISA. In vitro, the mouse RAW264.7 macrophage cell line was also cultured followed by various treatments. Expression of p-mTOR, NLRP3, activated caspase-1, and IL-1β in macrophages was determined.

RESULTS

Macrophages accumulated in the intestines and the expression of α7nAChR in the mucosal and submucosal layers of the intestines was increased in both the NEC patients and mice. The p-mTOR and CD68 were increased and co-localized in intestines of NEC patients. In vitro, α7nAChR agonist PNU-282987 significantly reduced the increase of NLRP3, activated caspase-1, and IL-1β in macrophages. PNU-282987 also significantly reduced the increase of p-mTOR. The effect was blocked by AMPK inhibitor compound C. The expression of NLRP3, activated caspase-1, and IL-1β was inhibited after mTOR inhibitor rapamycin treatment. In NEC model mice, PNU-282987 reduced the expression of p-mTOR, NLRP3, activated caspase-1, and IL-1β in the intestine. Meanwhile, rapamycin significantly attenuated NLRP3 activation and the release of IL-1β. Moreover, the proportion of intestinal macrophages and intestinal injury decreased after PNU-282987 treatment.

CONCLUSION

Macrophage α7nAChR activation mitigates NLRP3 inflammasome activation by modulating mTOR phosphorylation, and subsequently alleviates intestinal inflammation and injury in NEC.

Clinical Characteristics of Necrotizing Enterocolitis Diagnosed by Independent Adjudication of Abdominal Radiographs, Laparotomy, or Autopsy in Preterm Infants in the "Connection Trial"

OBJECTIVE

 Necrotizing enterocolitis (NEC) classically is diagnosed by radiographic demonstration of pneumatosis intestinalis/portal venous gas (PI/PVG). This study examines clinical characteristics of NEC confirmed by independent evaluation of abdominal radiographs, taken for clinical signs of NEC, or by pathologic findings at laparotomy or autopsy (confirmed NEC [cNEC]).

STUDY DESIGN

 The investigated cohort included 1,382 extremely low birth weight (BW) infants (BW range: 500-1,000 g) with median 27 weeks (range: 23-32) gestational age (GA) at birth. They were randomized into the placebo-controlled "Connection Trial" of the new biological drug candidate IBP-9414 with cNEC as one primary endpoint.

RESULTS

 Total 119 infants (8.6%) had cNEC diagnosed at median 14 days of age by confirming PI/PVG at X-ray adjudication (n = 111) and/or by surgery/autopsy (n = 21). Sixteen percent of cNEC cases died. Adverse events of NEC were reported in 8.5% of infants and 4.1% had NEC diagnosed by radiology and surgery/autopsy at the participating centers. Regression analyses showed that the risk of cNEC decreased by 11 to 30% for every 100-g increment in BW and single-week increment in GA and associated cNEC with odds ratios (ORs) > 2.0 for gastrointestinal (GI) perforation and obstruction, hypotension, hypokalemia, hypophosphatemia, and death. Comparing risks of cNEC in infants below and above 750-g BW showed higher ORs (2.7-4.3) for GI perforation, hypotension, hypokalemia, and renal complications in the smaller infants, whereas the bigger infants had higher ORs (1.9-3.2) for serious non-GI events, late-onset sepsis (LOS), and death. Predictors of cNEC (hazard ratio, HR > 1.5) included serious non-GI events (mainly infections), hyponatremia, and hyperglycemia, whereas the HR was 0.52 for intravenous antibiotics. After cNEC diagnosis, there were higher rates of GI perforation and obstruction, hypotension, hypokalemia, and LOS.

CONCLUSION

 Independent adjudication of abdominal radiographs increased radiological recognition of NEC and proved to be feasible in a multicenter study setting as well as able to diagnose clinically relevant NEC.

KEY POINTS

· Independent adjudication of abdominal radiographs in ELBW infants increased NEC recognition.. · Risk of NEC decreased by 11 to 30% with every 100-g increment in BW and GA week.. · In infants with BW 750 to 1,000 g, the risk of death from NEC was almost twice that in infants with BW 500 to 749 g. · Infants with NEC received antibiotics during one-third and parenteral nutrition during half of the first 7 postnatal weeks..

Mortality and neurodevelopmental outcomes at 2 years' corrected age of very preterm infants with necrotising enterocolitis or spontaneous intestinal perforation: The EPIPAGE-2 cohort study

PURPOSE

The primary objective was to evaluate the impact of necrotising enterocolitis (NEC) and spontaneous intestinal perforation (SIP) on mortality and neurodevelopmental outcomes at 2 years' corrected age (CA) in infants born before 32 weeks' gestation (WG).

METHODS

We studied neurodevelopment at 2 years' CA of infants with NEC or SIP who were born before 32 WG from the EPIPAGE-2 cohort study. The primary outcome was death or the presence of moderate-to-severe motor or sensory disability defined by moderate-to-severe cerebral palsy or hearing or visual disability. The secondary outcome was developmental delay defined by a score < 2 SDs below the mean for any of the five domains of the Ages and Stages Questionnaire.

RESULTS

At 2 years' CA, 46% of infants with SIP, 34% of infants with NEC, and 14% of control infants died or had a moderate-to-severe sensorimotor disability (p < 0.01). This difference was mainly due to an increase in in-hospital mortality in the infants with SIP or NEC. Developmental delay at 2 years' CA was more frequent for infants with SIP than controls (70.8% vs 44.0%, p = 0.02) but was similar for infants with NEC and controls (49.3% vs 44.0%, p = 0.5). On multivariate analysis, the likelihood of developmental delay was associated with SIP (adjusted odds ratio = 3.0, 95% CI 1.0-9.1) but not NEC as compared with controls.

CONCLUSION

NEC and SIP significantly increased the risk of death or sensorimotor disability at 2 years' CA. SIP was also associated with risk of developmental delay at 2 years' CA.

Human Milk Protein-Derived Bioactive Peptides from In Vitro-Digested Colostrum Exert Antimicrobial Activities against Common Neonatal Pathogens

Human milk reduces risk for necrotizing enterocolitis in preterm infants. Necrotizing enterocolitis occurs in the ileocecal region where thousands of milk protein-derived peptides have been released from digestion. Digestion-released peptides may exert bioactivity, such as antimicrobial and immunomodulatory activities, in the gut. In this study, we applied mass spectrometry-based peptidomics to characterize peptides present in colostrum before and after in vitro digestion. Sequence-based computational modeling was applied to predict peptides with antimicrobial activity. We identified more peptides in undigested samples, yet the abundances were much higher in the digested samples. Heatmapping demonstrated highly different peptide profiles between undigested and digested samples. Four peptides (αS1-casein [157-163], αS1-casein [157-165], β-casein [153-159] and plasminogen [591-597]) were selected, synthesized and tested against common pathogenic bacteria associated with necrotizing enterocolitis. All four exhibited bacteriostatic, though not bactericidal, activities against Klebsiella aerogenes, Citrobacter freundii and Serratia marcescens, but not Escherichia coli.

The Potential Value of Mean Platelet Volume and Platelet Distribution Width as Inflammatory Indicators in Surgical Necrotizing Enterocolitis

Background

This study aims to investigate the potential significance of mean platelet volume (MPV) and platelet distribution width (PDW) in predicting surgical neonatal necrotizing enterocolitis (NEC) and establish the correlation between MPV/PDW levels and the severity/prognosis of NEC.

Methods

A retrospective study was conducted on a cohort of 372 patients diagnosed with NEC. The patients were categorized into two groups based on whether they underwent surgical therapy. Univariate /multivariate analysis were employed to compare the MPV and PDW between the two groups. Moreover, patients in surgical group were categorized into multiple subgroups based on intraoperative findings and postoperative prognosis, and the levels of MPV and PDW were compared among these subgroups.

Results

Of the 372 patients, the operative group exhibited significantly higher levels of MPV and PDW than the nonoperative group (P < 0.05). Logistic regression analysis revealed that MPV (OR = 4.895, P < 0.001) and PDW (OR = 1.476, P < 0.001) independently associated with surgical NEC. The analysis of the receiver operating characteristic (ROC) curve revealed that the area under the curve (AUC) was 0.706 for MPV alone, with a cut-off value of 11.8 fL. Similarly, the AUC was 0.728 for PDW alone, with a cut-off value of 16%. However, when MPV and PDW were combined, the AUC increased to 0.906 for predicting surgical NEC. In accordance with the intraoperative findings, the levels of MPV and PDW were found to be higher in the large area necrosis group than in the partial or mild necrosis group (P < 0.01). Furthermore, the MPV and PDW values in the death group were significantly greater than those in the survival group (P =0.040, P =0.008).

Conclusion

MPV and PDW may serve as potentially valuable indicators for determining the need for surgical intervention and predicting the prognosis of patients with NEC.

[Research progress on the relationship between anemia and neonatal necrotizing enterocolitis]

Neonatal necrotizing enterocolitis (NEC) is the most common inflammatory intestinal disease in preterm infants, with a high incidence and mortality rate. The etiology and mechanisms of NEC are not yet fully understood, and multiple factors contribute to its occurrence and development. Recent studies have found that anemia is a risk factor for NEC in neonates, but the specific pathogenic mechanism remains unclear. This article reviews recent research on the relationship between anemia and NEC, providing a reference for further understanding the impact of anemia on intestinal injury and its association with NEC.

Do hematological biomarkers predict surgical necrotizing enterocolitis?

Necrotizing enterocolitis (NEC) is a devastating gastrointestinal emergency in preterm infants and the clinical presentation of NEC may vary with gestational age. We lack reliable biomarkers for early diagnosis of NEC limiting timely intervention. Hematological changes in NEC are actively researched for their potential role as biomarkers. The pattern and severity of hematological abnormalities have been correlated with rapid progression, the need for surgery, increased risk of mortality, and morbidity. In this issue of Pediatric Research, Chong et al. report GA-specific hematological biomarkers in preterm infants with NEC that could predict the need for surgery. Thrombocytopenia at NEC onset was an independent predictor of surgical intervention in extremely preterm infants. Persistent thrombocytopenia and lymphopenia at 72 h and elevated C-reactive protein at 48 h after NEC onset, predicted surgery in infants of 28 to <32 weeks GA. Persistent thrombocytopenia at 24 h after the onset of NEC was predictive of mortality in infants who underwent surgery. Well-designed, prospective, multi-center studies are needed to confirm the role of hematological biomarkers in early diagnosis and prognostication in NEC.

Core Outcome Set for Necrotizing Enterocolitis Treatment Trials

BACKGROUND AND OBJECTIVES

Variability in outcome reporting in necrotizing enterocolitis (NEC) treatment trials hinders conducting meta-analyses and implementing novel treatments. We aimed to develop a core outcome set (COS) for NEC treatment trials including outcome measures most relevant to patients and physicians, from NEC diagnosis to adulthood.

METHODS

Clinicians and/or researchers from low-middle- and high-income countries were approached based on their scientific contributions to NEC literature, and patients and parents through local organizations. We presented participants with 45 outcomes used in NEC research, identified through a systematic review. To achieve consensus, outcomes were rated on a scale of 1 to 9 in 3 online Delphi rounds, and discussed at a final consensus meeting.

RESULTS

Seventy-one participants from 25 countries completed all Delphi rounds, including 15 patients and family representatives. Thirteen outcomes reached consensus in one of the stakeholder groups and were included in the consensus meeting, 6 outcomes reached consensus in both groups. Twenty-seven participants from both high- and low-middle-income countries attended the online consensus meeting, including family representatives and NEC patients. After discussion and a final vote, 5 outcomes reached consensus to be included: mortality, NEC-related mortality, short bowel syndrome, quality of life, and neurodevelopmental impairment.

CONCLUSIONS

This NEC COS includes 5 predominantly long-term outcomes agreed upon by clinicians, patients, and family representatives. Use of this international COS will help standardize outcome selection in clinical trials, ensure these are relevant to those most affected by NEC care, and, ultimately, improve the care of infants with NEC.

Chromatin as alarmins in necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease primarily affecting premature neonates, marked by poorly understood pro-inflammatory signaling cascades. Recent advancements have shed light on a subset of endogenous molecular patterns, termed chromatin-associated molecular patterns (CAMPs), which belong to the broader category of damage-associated molecular patterns (DAMPs). CAMPs play a crucial role in recognizing pattern recognition receptors and orchestrating inflammatory responses. This review focuses into the realm of CAMPs, highlighting key players such as extracellular cold-inducible RNA-binding protein (eCIRP), high mobility group box 1 (HMGB1), cell-free DNA, neutrophil extracellular traps (NETs), histones, and extracellular RNA. These intrinsic molecules, often perceived as foreign, have the potential to trigger immune signaling pathways, thus contributing to NEC pathogenesis. In this review, we unravel the current understanding of the involvement of CAMPs in both preclinical and clinical NEC scenarios. We also focus on elucidating the downstream signaling pathways activated by these molecular patterns, providing insights into the mechanisms that drive inflammation in NEC. Moreover, we scrutinize the landscape of targeted therapeutic approaches, aiming to mitigate the impact of tissue damage in NEC. This in-depth exploration offers a comprehensive overview of the role of CAMPs in NEC, bridging the gap between preclinical and clinical insights.

Epigenetic Insights Into Necrotizing Enterocolitis: Unraveling Methylation-Regulated Biomarkers

Necrotizing enterocolitis (NEC) is a multifactorial gastrointestinal disease with high morbidity and mortality among premature infants. This study aimed to identify novel methylation-regulated biomarkers in NEC intestinal tissue through multiomics analysis. We analyzed DNA methylation and transcriptome datasets from ileum and colon tissues of patients with NEC. We identify methylation-related differential genes (MrDEGs) based on the rule that the degree of methylation in the promoter region is inversely proportional to RNA transcription. These MrDEGs included ADAP1, GUCA2A, BCL2L14, FUT3, MISP, USH1C, ITGA3, UNC93A and IL22RA1. Single-cell data revealed that MrDEGs were mainly located in the intestinal epithelial part of intestinal tissue. These MrDEGs were verified through Target gene bisulfite sequencing and RT-qPCR. We successfully identified and verified the ADAP1, GUCA2A, IL22RA1 and MISP, primarily expressed in intestinal epithelial villus cells through single-cell data. Through single-gene gene set enrichment analysis, we found that these genes participate mainly in the pathological process of T-cell differentiation and the suppression of intestinal inflammation in NEC. This study enhances our understanding of the pathogenesis of NEC and may promote the development of new precision medicine methods for NEC prediction and diagnosis.

Transcriptomic analysis of the effect of remote ischaemic conditioning in an animal model of necrotising enterocolitis

Necrotising enterocolitis (NEC) has a complex pathophysiology but the common end-point is ischaemia reperfusion injury (IRI) and intestinal necrosis. We have previously reported that RIC significantly reduces the intestinal injury in a rat model of NEC. Here we describe the changes in intestinal mRNA occurring in the intestine of animals exposed to IRI, both with and without RIC. Related rat-pups were randomly assigned to four groups: SHAM, IRI only, RIC only and RIC + IRI. IRI animals, underwent 40 min of intestinal ischaemia, and 90 min of reperfusion. Animals that underwent RIC had three cycles of 5 min of alternating ischaemia/reperfusion by means of a ligature applied to the hind limb. Samples from the terminal ileum were immediately stored in RNA-preserving media for later next generation sequencing and transciptome analysis using R v 3.6.1. Differential expression testing showed that 868 genes differentially expressed in animals exposed to RIC alone compared to SHAM and 135 in the IRI and RIC group compared to IRI alone. Comparison between these two sets showed that 25 genes were differentially expressed in both groups. Pro-inflammatory molecules: NF-ĸβ2, Cxcl1, SOD2 and Map3k8 all show reduced expression in response to RIC. Targeted gene analysis revealed increased expression in PI3K which is part of the so-called RISK-pathway which is a key part of the protective mechanisms of RIC in the heart. Overall, this transcriptomic analysis shows that RIC provides a protective effect to the intestine via anti-inflammatory pathways. This could be particularly relevant to treating and preventing NEC.

Neonatal Necrotizing Enterocolitis: An Update on Pathophysiology, Treatment, and Prevention

Necrotizing enterocolitis (NEC) is a life-threatening disease predominantly affecting premature and very low birth weight infants resulting in inflammation and necrosis of the small bowel and colon and potentially leading to sepsis, peritonitis, perforation, and death. Numerous research efforts have been made to better understand, treat, and prevent NEC. This review explores a variety of factors involved in the pathogenesis of NEC (prematurity, low birth weight, lack of human breast milk exposure, alterations to the microbiota, maternal and environmental factors, and intestinal ischemia) and reports treatment modalities surrounding NEC, including pain medications and common antibiotic combinations, the rationale for these combinations, and recent antibiotic stewardship approaches surrounding NEC treatment. This review also highlights the effect of early antibiotic exposure, infections, proton pump inhibitors (PPIs), and H2 receptor antagonists on the microbiota and how these risk factors can increase the chances of NEC. Finally, modern prevention strategies including the use of human breast milk and standardized feeding regimens are discussed, as well as promising new preventative and treatment options for NEC including probiotics and stem cell therapy.

Bedside Ultrasound for Early Diagnosis of Necrotizing Enterocolitis: A Pilot Study

OBJECTIVE

This study aimed to assess whether bedside ultrasound (BUS) as the first imaging modality allows an earlier diagnosis of necrotizing enterocolitis (NEC) compared with abdominal radiography.

STUDY DESIGN

A before-after controlled study in preterm infants with suspected NEC. The intervention group (October 2019-October 2021) received BUS as the first imaging modality and was managed accordingly to BUS findings. The control group (October 2015-September 2019) received radiography as the first imaging modality. The main outcome was NEC confirmation at the time of initial imaging. Secondary outcomes included time to diagnosis, laboratory data, and treatment requirements.

RESULTS

Thirty-five episodes of suspected NEC with 14 (40%) confirmed NEC cases and 49 episodes of suspected NEC with 22 (44.9%) confirmed NEC cases were included in the intervention and control groups, respectively. In the intervention group, 11 of 14 (78.6%) NEC cases were confirmed at initial evaluation compared with 5 of 22 (22.7%) in the control group (p = 0.001). Infants in the intervention group developed thrombocytopenia and coagulopathy less frequently, were exposed to less radiation, and required less days of parenteral nutrition compared with the control group (p < 0.05).

CONCLUSION

The use of BUS as the first imaging modality allowed an earlier diagnosis and timely treatment of NEC compared with abdominal radiography.Key Points · This is the first study that has assessed the role of BUS as the first imaging modality in NEC.. · BUS improves early diagnosis of NEC compared with abdominal radiography.. · BUS shortens time to NEC confirmation and treatment initiation which may reduce clinical severity of the NEC episode..

Necrotizing Enterocolitis in Very Low Birth Weight Neonates: A Natural History Study

OBJECTIVE

We characterize the most recent natural history of necrotizing enterocolitis (NEC), as this is an essential first step in guiding the prevention and treatment of this disease in the present day.

STUDY DESIGN

We performed a retrospective cohort study of neonates who were born at 23 to 29 weeks' gestation and birth weight <1,500 g who received care from the Pediatrix Medical Group between 2004 and 2019. We assessed the incidence of medical and surgical NEC and the patterns of initial antibiotic treatment to develop a contemporary cohort for further analysis. Among patients discharged between 2015 and 2019, we characterized the stage-specific risk factors for patients diagnosed with medical or surgical NEC, as well as patterns of disease onset, progression, biomarkers, and outcomes. We used the same approach to characterize patients diagnosed with suspected NEC.

RESULTS

Among 34,032 patients in the contemporary cohort, 1,150 (3.4%) were diagnosed with medical NEC and 543 (1.6%) were diagnosed with surgical NEC. The temporal pattern of disease onset was different for medical and surgical NEC, with gestational age- and birth weight-specific risk disparities emerging earlier in surgical NEC. Thirty-day mortality was much greater among surgical NEC patients (medical NEC 16.4% vs. surgical NEC 43.0%), as were rates of various in-hospital and long-term outcomes. Suspected NEC was diagnosed in 1,256 (3.7%) patients, among whom risk factors and disease onset, progression, and outcomes closely resembled those of medical NEC.

CONCLUSION

Analyzing data from a contemporary cohort enabled us to characterize the current, stage-specific natural history of NEC, including novel insights into suspected NEC. Future studies could leverage this cohort to characterize how specific patient characteristics, care processes, or biomarkers may influence or predict disease outcomes.

KEY POINTS

· The incidence of NEC has reached a stable baseline in recent years.. · Risk factors for NEC vary in a stage-specific manner.. · The stage-specific onset and progression of NEC differ by gestational age and birth weight..

Quality of life after necrotizing enterocolitis: an integrative review

OBJECTIVE

To describe the long-term health outcomes of neonates affected by necrotizing enterocolitis (NEC) and its implications for quality of life.

DATA SOURCE

This is an integrative review, conducted by searching the literature in the following databases: Virtual Health Library (BVS), Latin American and Caribbean Health Sciences Literature (LILACS), Medical Literature Analysis and Retrieval System Online (MEDLINE), and PubMed, using Health Sciences Descriptors (DeCS): "necrotizing enterocolitis," "quality of life," and "prognosis" combined with the Boolean operators AND and OR: "quality of life" OR "prognosis." Inclusion criteria were: publication period between 2012 and 2022.

DATA SYNTHESIS

A total of 1,010 studies were located, of which ten were selected to comprise the bibliographic sample of this review. Children with NEC are prone to exhibit cognitive neurological impairment, especially those who undergo surgical procedures due to more severe conditions. Motor development was considered below average when compared to healthy children, with more noticeable delays in fine and gross motor function development. The search for the relationship between NEC and quality of life revealed that this condition has a negative impact on the well-being of affected individuals.

CONCLUSIONS

NEC has proven to be a serious condition contributing to high rates of morbidity and mortality in newborns, potentially leading to a reduction in the quality of life of affected patients.

DNA methylation in necrotizing enterocolitis

Epigenetic modifications, such as DNA methylation, are enzymatically regulated processes that directly impact gene expression patterns. In early life, they are central to developmental programming and have also been implicated in regulating inflammatory responses. Research into the role of epigenetics in neonatal health is limited, but there is a growing body of literature related to the role of DNA methylation patterns and diseases of prematurity, such as the intestinal disease necrotizing enterocolitis (NEC). NEC is a severe intestinal inflammatory disease, but the key factors that precede disease development remain to be determined. This knowledge gap has led to a failure to design effective targeted therapies and identify specific biomarkers of disease. Recent literature has identified altered DNA methylation patterns in the stool and intestinal tissue of neonates with NEC. These findings provide the foundation for a new avenue in NEC research. In this review, we will provide a general overview of DNA methylation and then specifically discuss the recent literature related to methylation patterns in neonates with NEC. We will also discuss how DNA methylation is used as a biomarker for other disease states and how, with further research, methylation patterns may serve as potential biomarkers for NEC.

Quality of Life in Long-Term Survivors of Surgical Necrotizing Enterocolitis

OBJECTIVE

This study evaluated the quality of life (QoL) in patients who have recovered from surgical necrotizing enterocolitis (NEC).

METHODS

This is a cross-sectional study conducted in a tertiary centre and patients who have received surgery for NEC between 2000 and 2014 were invited to participate. The Pediatric Quality of Life Inventory Generic (PedsQL™) Core Scale Version 4.0 was used as the assessment tool. Values were reported as median (interquartile rage) and compared with age-matched controls.

RESULTS

During the study period, 90 patients were eligible for the study and 29 patients have completed the survey. There was no gender difference and the median age was 10 years (9-13 years). Nine patients have suffered from short bowel syndrome (SBS) as a result of the surgery. For the QoL assessment, 17 participants have completed both parent proxy and child-rated survey; 11 completed the parent-rated survey and 1 completed child-rated survey only. The scores for parent-rated survey were - overall: 86.4 (70.7-92.7); physical: 95.3 (83.6-100) and psychosocial: 82.5 (66.3-90.4). The scores for child-rated survey were - overall: 82.1 (73.4-96.2); physical: 96.9 (90.6-99.2) and psychosocial: 81.7 (64.2-95.8). Regarding the impact of previous SBS on the QoL, there were no significant difference in the overall score for both parent proxy and child-rated survey (SBS-ve vs + ve) (parent-rated: 87.5 vs 85.3, p = 0.849; child-rated: 81.0 vs 88.0, p = 0.503). There were also no differences in physical and psychosocial assessments (parent-rated: [physical] 95.3 vs 95.3, p = 0.267; [psychosocial] 84.2 vs 80.0, p = 0.274; child-rated: [physical] 95.3 vs 96.9, p = 0.395; [psychosocial] 79.2 vs 87.5, p = 0.611).

CONCLUSION

The QoL in long-term survivors of surgical NEC without major medical illnesses is comparable to normal population. However, they may have a lower psychosocial well-being that should be addressed. Previous history of SBS does not have a significant impact on the future QoL.

LEVEL OF EVIDENCE

III.

Risk factors of necrotizing enterocolitis in twin preterm infants

PURPOSE

This study was aimed to investigate the risk factors of necrotizing enterocolitis (NEC) in twin preterm infants.

METHODS

The clinical data of 67 pairs of twin preterm infants admitted to the neonatal department of our hospital from January 2010 to December 2021 were retrospectively collected. One of the twins had NEC (Bell II and above) and the other twin without NEC. They were divided into NEC group and control group according to whether NEC occurred or not.

RESULTS

Univariate analysis showed that NEC was associated with congenital heart disease, small for gestational age, mild asphyxia at birth and feeding intolerance (P < 0.05).

CONCLUSION

Occurrence of NEC was associated with congenital heart disease, small for gestational age, and asphyxia at birth. For twin preterm infants with congenital heart disease, small for gestational age, or asphyxia at birth, special attention should be paid to the occurrence of NEC to minimize and avoid the occurrence of NEC.

The role of nutrition in analysis of risk factors and short-term outcomes for late-onset necrotizing enterocolitis among very preterm infants: a nationwide, multicenter study in China

BACKGROUND

Necrotizing enterocolitis (NEC) is a serious gastrointestinal disease, primarily affects preterm newborns and occurs after 7 days of life (late-onset NEC, LO-NEC). Unfortunately, over the past several decades, not much progress has been made in its treatment or prevention. This study aimed to analyze the risk factors for LO-NEC, and the impact of LO-NEC on short-term outcomes in very preterm infants (VPIs) with a focus on nutrition and different onset times.

METHOD

Clinical data of VPIs were retrospectively collected from 28 hospitals in seven different regions of China from September 2019 to December 2020. A total of 2509 enrolled VPIs were divided into 2 groups: the LO-NEC group and non-LO-NEC group. The LO-NEC group was divided into 2 subgroups based on the onset time: LO-NEC occurring between 8 ~ 14d group and LO-NEC occurring after 14d group. Clinical characteristics, nutritional status, and the short-term clinical outcomes were analyzed and compared among these groups.

RESULTS

Compared with the non-LO-NEC group, the LO-NEC group had a higher proportion of anemia, blood transfusion, and invasive mechanical ventilation (IMV) treatments before NEC; the LO-NEC group infants had a longer fasting time, required longer duration to achieve the target total caloric intake (110 kcal/kg) and regain birthweight, and showed slower weight growth velocity; the cumulative dose of the medium-chain and long-chain triglyceride (MCT/LCT) emulsion intake in the first week after birth was higher and breastfeeding rate was lower. Additionally, similar results including a higher proportion of IMV, lower breastfeeding rate, more MCT/LCT emulsion intake, slower growth velocity were also found in the LO-NEC group occurring between 8 ~ 14d when compared to the LO-NEC group occurring after 14 d (all (P < 0.05). After adjustment for the confounding factors, high proportion of breastfeeding were identified as protective factors and long fasting time before NEC were identified as risk factors for LO-NEC; early feeding were identified as protective factors and low gestational age, grade III ~ IV neonatal respiratory distress syndrome (NRDS), high accumulation of the MCT/LCT emulsion in the first week were identified as risk factors for LO-NEC occurring between 8 ~ 14d. Logistic regression analysis showed that LO-NEC was a risk factor for late-onset sepsis, parenteral nutrition-associated cholestasis, metabolic bone disease of prematurity, and extrauterine growth retardation.

CONCLUSION

Actively preventing premature birth, standardizing the treatment of grade III ~ IV NRDS, and optimizing enteral and parenteral nutrition strategies may help reduce the risk of LO-NEC, especially those occurring between 8 ~ 14d, which may further ameliorate the short-term clinical outcome of VPIs.

TRIAL REGISTRATION

ChiCTR1900023418 (26/05/2019).

Factors affecting neurodevelopmental outcome following surgical necrotising enterocolitis: a systematic review

Surgically treated necrotising enterocolitis (sNEC) is associated with significantly worse neurodevelopmental outcomes than that seen in premature infants without NEC. We aim to review the association between factors involved in the surgical treatment of NEC and subsequent neurodevelopmental outcomes to identify potential areas for improvement. The PubMed and Embase databases were interrogated for articles reporting neurodevelopmental outcomes in babies treated surgically for NEC using key terms including: "Infant", "Necrotising enterocolitis", "Surgical", "Neurodevelopmental" and "Outcomes". The search strategy yielded 1170 articles and after applying inclusion and exclusion criteria 22 studies remained and formed the review. A diverse range of neurodevelopmental outcomes were reported. Extreme prematurity and lower birth weight were associated with worse neurodevelopmental outcomes. The use of peritoneal drains and enterostomies were associated with worse outcomes. Modifications to surgical strategies in NEC may improve neurodevelopmental outcomes but the effect of confounding factors remains unclear. Further large scale studies are required to define the optimum strategies for treating NEC surgically and to develop a core outcome set for research into NEC.

Outcomes by disease onset, sex, and intervention in neonates with SIP and surgical NEC

BACKGROUND

Outcomes of infants following surgical necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) categorized by the age of onset, interventions, and sex are not well defined.

METHODS

Retrospective comparison of infants categorized by age of onset (NEC at <10, 10-20, and >20 days) and SIP at <7 versus ≥7 days), sex, and intervention [Penrose Drain (PD) vs. laparotomy].

RESULTS

A total of 114 infants had NEC and 37 had SIP. On multinomial logistic regression, infants with NEC/SIP onset >20 days had significantly lower odds of small bowel involvement (aOR = 0.07, 95% CI: 0.01-0.33, p = 0.001), higher necrosis (aOR = 3.59, 95% CI: 1.34-9.65, p = 0.012) and higher CRP (p = 0.004) than onset <10 days. Initial laparotomy was associated with more bowel loss (24.1 cm [12.3; 40.6] vs.12.1 [8.00; 23.2]; p = 0.001), small and large intestine involvement (47.1% vs 17.2%; p = 0.01), and ileocecal valve resection (42% vs. 19.4%; p = 0.036) than initial PD therapy. Females underwent fewer small bowel resections (52.3% vs 73.6%; p = 0.025) but had higher surgical morbidity (53.7% vs. 24.7%.; p = 0.001) than males.

CONCLUSION

Clinical, radiological, and histopathological presentation and outcomes in preterm infants with surgical NEC/SIP are associated with age of disease onset, sex, and initial intervention.

IMPACT

Neonates with surgical NEC onset >20 days had more severe necrosis, inflammation, kidney injury, and bowel loss than those with <10 days. Initial laparotomy was associated with later age onset, more bowel loss, and ileocecal valve resection compared to initial PD treatment, but not with differences in mortality or length of stay. Female sex was associated with lower maturity, more placental malperfusion, less often small bowel involvement, lower pre-NEC hematocrit as well as higher surgical morbidity than males. Whether the management of surgical NEC and SIP should differ by the age of onset requires further investigation.

Surgical Necrotizing Enterocolitis - Can We Predict the Need for Gastrostomy Tube Placement?

INTRODUCTION

Necrotizing enterocolitis (NEC) is a significant cause of morbidity and mortality among extremely premature infants. Approximately 50% of cases progress to surgery, frequently resulting in resection of necrotic bowel and ostomy creation. Premature neonates are at risk for bronchopulmonary dysplasia and feeding failure; surgery in these patients is higher risk. We evaluated the incidence of gastrostomy tube (GT) placement after ostomy reversal in surgical NEC to define a subset of patients who would benefit from concurrent ostomy reversal and GT placement.

METHODS

A single-center retrospective study of infants with surgical NEC requiring ostomy creation between 2007 and 2021 was performed.

RESULTS

Eighty patients met inclusion criteria. A GT was placed in 45/80 (56.3%), of which 3/45 (6.7%) were placed before, 20/45 (44.4%) concurrently with, and 22/45 (48.9%) after ostomy reversal. Between those who did and did not require GT placement, there were no significant differences in gestational age (27 versus 27 wk, P = 0.94) or birth weight (830 g versus 1055 g, P = 0.36). Hospital length of stay was longer in the GT group (128.2 versus 70.9 d, P < 0.0001). Time from ostomy reversal to hospital discharge was shorter when performed concurrently with GT (56 versus 77 d, P = 0.02). There were no differences in short-term or long-term GT related complications based on timing of GT placement.

CONCLUSIONS

GT placement occurred in approximately 50% of patients with surgical NEC and GT may be accomplished safely at the time of ostomy reversal thus reducing the need for an additional procedure.

Factors influencing necrotizing enterocolitis in premature infants in China: a systematic review and meta-analysis

BACKGROUND

Necrotizing enterocolitis (NEC) is a multifactorial gastrointestinal disease with high morbidity and mortality among premature infants. However, studies with large samples on the factors of NEC in China have not been reported. This meta-analysis aims to systematically review the literature to explore the influencing factors of necrotizing enterocolitis in premature infants in China and provide a reference for the prevention of NEC.

METHODS

PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM), Wanfang and VIP databases were systematically searched from inception to February 2023. We used Stata14.0 software to perform the systematic review and meta-analysis. We used fixed or random effects models with combined odds ratios (ORs) and 95% confidence intervals (CIs), and quality was evaluated using the Newcastle‒Ottawa Scale (NOS).

RESULTS

The total sample was 8616 cases, including 2456 cases in the intervention group and 6160 cases in the control group. It was found that 16 risk factors and 3 protective factors were related to necrotizing enterocolitis in premature infants. Septicemia (OR = 3.91), blood transfusion (OR = 2.41), neonatal asphyxia (OR = 2.46), pneumonia (OR = 6.17), infection (OR = 5.99), congenital heart disease (OR = 4.80), intrahepatic cholestasis of pregnancy (ICP) (OR = 2.71), mechanical ventilation (OR = 1.44), gestational diabetes mellitus (GDM) (OR = 3.08), respiratory distress syndrome (RDS) (OR = 3.28), hypoalbuminemia (OR = 2.80), patent ductus arteriosus (PDA) (OR = 3.10), respiratory failure (OR = 7.51), severe anemia (OR = 2.86), history of antibiotic use (OR = 2.12), and meconium-stained amniotic fluid (MSAF) (OR = 3.14) were risk factors for NEC in preterm infants in China. Breastfeeding (OR = 0.31), oral probiotics (OR = 0.36), and prenatal use of glucocorticoids (OR = 0.38) were protective factors for NEC in preterm infants.

CONCLUSIONS

Septicemia, blood transfusion, neonatal asphyxia, pneumonia, infection, congenital heart disease, ICP, GDM, RDS, hypoproteinemia, PDA, respiratory failure, severe anemia, history of antibiotic use and MSAF will increase the risk of NEC in premature infants, whereas breastfeeding, oral probiotics and prenatal use of glucocorticoids reduce the risk. Due to the quantity and quality of the included literature, the above findings need to be further validated by more high-quality studies.

Risk factor analysis and nomogram prediction model construction for NEC complicated by intestinal perforation

OBJECTIVE

To investigate the clinical characteristics of neonatal necrotizing enterocolitis (NEC) complicated by intestinal perforation and predict the incidence of intestinal perforation in NEC.

METHODS

Neonates diagnosed with NEC at the Affiliated Hospital of Zunyi Medical University from January 2012 to May 2022 were enrolled, and the clinical data were collected and analyzed retrospectively. The patients were divided into two groups based on intestinal perforation occurrence or not. Mann-Whitney U tests, t-tests, chi-square tests, and fisher's exact tests were performed between-group comparisons. Logistic and lasso regressions were applied to screen independent risk factors for concomitant bowel perforation, and R software (RMS package) was used to formulate the nomogram prediction model. In addition, the receiver operating curve (ROC) and the calibration curve were drawn to verify the predictive power, while decision curve analysis (DCA) was constructed to evaluate the clinical applicability of the nomogram model.

RESULTS

One hundred eighty neonates with NEC were included, of which 48 had intestinal perforations, and 132 did not; the overall incidence of intestinal perforation was 26.67% (48/180). Bloody stool (OR = 5.60), APTT ≥ 50 s (OR = 3.22), thrombocytopenia (OR = 4.74), and hypoalbuminemia (OR = 5.56) were identified as independent risk variables for NEC intestinal perforation (P < 0.05) through multivariate logistic regression analysis. These factors were then applied to develop a nomogram prediction model (C-index = 0.838) by using the R software. The area under the curve (AUC) for the nomogram in the training and validation cohorts were 0.838 (95% Cl: 0.768, 0.908) and 0.802 (95% CI: 0.659, 0.944), respectively. The calibration curve shown that the nomogram has a good predictive ability for predicting the risk of intestinal perforation occurrence. And the decision curve and clinical impact curve analyses demonstrated good clinical utility of the nomogram model.

CONCLUSION

We found that Bloody stool, APTT ≥ 50 s, Thrombocytopenia, and hypoalbuminemia could be used as independent risk factors for predicting intestinal perforation in neonates with NEC. The nomogram model based on these variables had high predictive values to identify NEC patients with intestinal perforation.

Nomogram to predict risk of neonatal mortality among preterm neonates admitted with sepsis at University of Gondar Comprehensive Specialized Hospital: risk prediction model development and validation

BACKGROUND

Mortality in premature neonates is a global public health problem. In developing countries, nearly 50% of preterm births ends with death. Sepsis is one of the major causes of death in preterm neonates. Risk prediction model for mortality in preterm septic neonates helps for directing the decision making process made by clinicians.

OBJECTIVE

We aimed to develop and validate nomogram for the prediction of neonatal mortality. Nomograms are tools which assist the clinical decision making process through early estimation of risks prompting early interventions.

METHODS

A three year retrospective follow up study was conducted at University of Gondar Comprehensive Specialized Hospital and a total of 603 preterm neonates with sepsis were included. Data was collected using KoboCollect and analyzed using STATA version 16 and R version 4.2.1. Lasso regression was used to select the most potent predictors and to minimize the problem of overfitting. Nomogram was developed using multivariable binary logistic regression analysis. Model performance was evaluated using discrimination and calibration. Internal model validation was done using bootstrapping. Net benefit of the nomogram was assessed through decision curve analysis (DCA) to assess the clinical relevance of the model.

RESULT

The nomogram was developed using nine predictors: gestational age, maternal history of premature rupture of membrane, hypoglycemia, respiratory distress syndrome, perinatal asphyxia, necrotizing enterocolitis, total bilirubin, platelet count and kangaroo-mother care. The model had discriminatory power of 96.7% (95% CI: 95.6, 97.9) and P-value of 0.165 in the calibration test before and after internal validation with brier score of 0.07. Based on the net benefit analysis the nomogram was found better than treat all and treat none conditions.

CONCLUSION

The developed nomogram can be used for individualized mortality risk prediction with excellent performance, better net benefit and have been found to be useful in clinical practice with contribution in preterm neonatal mortality reduction by giving better emphasis for those at high risk.

More than nutrition: Therapeutic potential and mechanism of human milk oligosaccharides against necrotizing enterocolitis

Human milk is the most valuable source of nutrition for infants. The structure and function of human milk oligosaccharides (HMOs), which are key components of human milk, have long been attracting particular research interest. Several recent studies have found HMOs to be efficacious in the prevention and treatment of necrotizing enterocolitis (NEC). Additionally, they could be developed in the future as non-invasive predictive markers for NEC. Based on previous findings and the well-defined functions of HMOs, we summarize potential protective mechanisms of HMOs against neonatal NEC, which include: modulating signal receptor function, promoting intestinal epithelial cell proliferation, reducing apoptosis, restoring intestinal blood perfusion, regulating microbial prosperity, and alleviating intestinal inflammation. HMOs supplementation has been demonstrated to be protective against NEC in both animal studies and clinical observations. This calls for mass production and use of HMOs in infant formula, necessitating more research into the safety of industrially produced HMOs and the appropriate dosage in infant formula.

NLRP3 activation in macrophages promotes acute intestinal injury in neonatal necrotizing enterocolitis

BACKGROUND

Macrophages are involved in various immune inflammatory disease conditions. This study aimed to investigate the role and mechanism of macrophages in regulating acute intestinal injury in neonatal necrotizing enterocolitis (NEC).

METHODS

CD68, nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing 3 (NLRP3), cysteine aspartate-specific protease-1 (caspase-1), and interleukin-1β (IL-1β) in paraffin sections of intestinal tissues from NEC and control patients were detected with immunohistochemistry, immunofluorescence, and western blot. Hypertonic pet milk, hypoxia and cold stimulation were used to establish a mouse (wild type and Nlrp3-/-) model of NEC. The mouse macrophage (RAW 264.7) and rat intestinal epithelial cell-6 lines were also cultured followed by various treatments. Macrophages, intestinal epithelial cell injuries, and IL-1β release were determined.

RESULTS

Compared to the gut "healthy" patients, the intestinal lamina propria of NEC patients had high macrophage infiltration and high NLRP3, caspase-1, and IL-1β levels. Furthermore, in vivo, the survival rate of Nlrp3-/- NEC mice was dramatically improved, the proportion of intestinal macrophages was reduced, and intestinal injury was decreased compared to those of wild-type NEC mice. NLRP3, caspase-1, and IL-1β derived from macrophages or supernatant from cocultures of macrophages and intestinal epithelial cells also caused intestinal epithelial cell injuries.

CONCLUSIONS

Macrophage activation may be essential for NEC development. NLRP3/caspase-1/IL-1β cellular signals derived from macrophages may be the underlying mechanism of NEC development, and all these may be therapeutic targets for developing treatments for NEC.

Necrotizing enterocolitis: current understanding of the prevention and management

Necrotizing enterocolitis (NEC) is one of the diseases in neonates, with a high morbidity and mortality rate, especially in preterm infants. This review aimed to briefly introduce the latest epidemiology, susceptibility factors, and clinical diagnosis and presentation of NEC. We also organized new prevention strategies by risk factors according to different pathogeneses and then discussed new treatment methods based on Bell's staging and complications, and the classification of mild to high severity based on clinical and imaging manifestations. Such a generalization will help clinicians and researchers to gain a deeper understanding of the disease and to conduct more targeted classification, grading prevention, and exploration. We focused on prevention and treatment of the early and suspected stages of NEC, including the discovery of novel biomarkers and drugs to control disease progression. At the same time, we discussed its clinical application, future development, and shortcomings.

Fecal virus-like particles are sufficient to reduce necrotizing enterocolitis

Fecal filtrate transfer (FFT) is emerging as a safer alternative to traditional fecal microbiota transplantation (FMT) - particularly in the context of necrotizing enterocolitis (NEC), a severe gastrointestinal condition affecting preterm infants. Using a preterm piglet model, FFT has demonstrated superiority over FMT in safety and NEC prevention. Since FFT is virtually devoid of bacteria, prokaryotic viruses (bacteriophages) are assumed to mediate the beneficial effects. However, this assumption remains unproven. To address this gap, we separated virus-like particles (30 kDa to 0.45 µm) of donor feces from the residual postbiotic fluid. We then compared clinical and gut microbiota responses to these fractions with the parent FFT solution after transferring them to NEC-susceptible preterm piglets. Virome transfer was equally effective as FFT in reducing the severity of NEC-like pathology. The bacterial compositional data corroborated clinical findings as virome transfer reduced the relative abundance of several NEC-associated pathogens e.g. Klebsiella pneumoniae and Clostridium perfringens. Virome transfer diversified gut viral communities with concomitant constraining effects on the bacterial composition. Unexpectedly, virome transfer, but not residual postbiotic fluid, led to earlier diarrhea. While diarrhea may be a minor concern in human infants, future work should identify ways of eliminating this side effect without losing treatment efficacy.

Cholestasis is associated with a higher rate of complications in both medical and surgical necrotizing enterocolitis

OBJECTIVE

To evaluate the relationship between cholestasis and outcomes in medical and surgical necrotizing enterocolitis (NEC).

STUDY DESIGN

A retrospective analysis of prospectively collected data from 1472 infants with NEC [455 medical (mNEC) and 1017 surgical (sNEC)] from the Children's Hospital Neonatal Database.

RESULTS

The prevalence of cholestasis was lower in mNEC versus sNEC (38.2% vs 70.1%, p < 0.001). In both groups, cholestasis was associated with lower birth gestational age [mNEC: OR 0.79 (95% CI 0.68-0.92); sNEC: OR 0.86 (95% CI 0.79-0.95)] and increased days of parenteral nutrition [mNEC: OR 1.08 (95% CI 1.04-1.13); sNEC: OR 1.01 (95% CI 1.01-1.02)]. For both groups, the highest direct bilirubin was associated with the composite outcome mortality or length of stay >75th percentile [mNEC: OR 1.21 (95% CI 1.06-1.38); sNEC: OR 1.06 (95% CI 1.03-1.09)].

CONCLUSION

Cholestasis with both medical NEC and surgical NEC is associated with adverse patient outcomes including increased mortality or extreme length of stay.

Factors associated with the increased incidence of necrotising enterocolitis in extremely preterm infants in Sweden between two population-based national cohorts (2004-2007 vs 2014-2016)

OBJECTIVE

To investigate potential risk factors behind the increased incidence of necrotising enterocolitis (NEC) in Swedish extremely preterm infants.

DESIGN

Registry data from two population-based national cohorts were studied. NEC diagnoses (Bell stage ≥II) were validated against hospital records.

PATIENTS

All liveborn infants <27 weeks of gestation 2004-2007 (n=704) and 2014-2016 (n=895) in Sweden.

MAIN OUTCOME MEASURES

NEC incidence.

RESULTS

The validation process resulted in a 28% reduction of NEC cases but still confirmed a higher NEC incidence in the later epoch compared with the earlier (73/895 (8.2%) vs 27/704 (3.8%), p=0.001), while the composite of NEC or death was lower (244/895 (27.3%) vs 229/704 (32.5%), p=0.022). In a multivariable Cox regression model, censored for mortality, there was no significant difference in early NEC (0-7 days of life) between epochs (HR=0.9 (95% CI 0.5 to 1.9), p=0.9), but being born in the later epoch remained an independent risk factor for late NEC (>7 days) (HR=2.7 (95% CI 1.5 to 5.0), p=0.001). In propensity score analysis, a significant epoch difference in NEC incidence (12% vs 2.8%, p<0.001) was observed only in the tertile of infants at highest risk of NEC, where the 28-day mortality was lower in the later epoch (35% vs 50%, p=0.001). More NEC cases were diagnosed with intramural gas in the later epoch (33/73 (45.2%) vs 6/26 (23.1%), p=0.047).

CONCLUSIONS

The increase in NEC incidence between epochs was limited to cases occurring after 7 days of life and was partly explained by increased survival in the most extremely preterm infants. Misclassification of NEC is common.

A Quality Improvement Initiative to Reduce Necrotizing Enterocolitis in Very Preterm Infants

OBJECTIVE

To reduce the incidence of necrotizing enterocolitis (NEC) among very preterm infants in the Calgary Health Region to ≤2% within 2 years.

METHODS

A multidisciplinary team developed key drivers for NEC. Targeted interventions included strategies to increase mothers' own milk (MOM), improve compliance with feeding regimens, standardize management of feeding intolerance, prevent intestinal microbial aberrations, and feed conservatively during blood transfusion and the treatment of patent ductus arteriosus. The outcome measure was NEC (≥ stage 2). Changes in NEC rates were examined among racial and ethnic groups. Process measures included MOM feeding at discharge, the difference between actual and expected time to reach full feeds, lowest hemoglobin, and the duration of empirical antibiotics. Growth, the rate of blood transfusion, and the duration of parenteral nutrition were balancing measures. The preintervention, intervention, and sustainment periods were January 2013 to June 2016, July 2016 to December 2018, and December 2018 to December 2021, respectively.

RESULTS

We included 2787 infants born at ≤326/7 weeks' gestation (1105 preintervention, 763 during intervention, and 919 in sustainment). NEC decreased from 5.6% to 1.9%. Process measures indicated increased MOM feeding at discharge, improved compliance with feeding regimens, increased lowest hemoglobin levels, and shorter durations of empirical antibiotics. Balancing measures revealed improved weight Z-scores, shorter durations on parenteral nutrition, and increased rates of blood transfusion.

CONCLUSIONS

Quality improvement initiatives to increase MOM, improve compliance with feeding regimens, feed conservatively during blood transfusion and treatment of patent ductus arteriosus, and prevent intestinal microbial aberrations were associated with reduced NEC.

High-dimensional mass cytometry reveals systemic and local immune signatures in necrotizing enterocolitis

Objective

Patients with necrotizing enterocolitis display severe gastrointestinal complications of prematurity, but the mechanism driving this clinical profile remains unknown. We used mass cytometry time-of-flight to characterize and compare immune cell populations in the blood and intestine tissue from patients with and without (controls) necrotizing enterocolitis at single-cell resolution.

Methods

We completed a deep mapping of the immune system of the peripheral blood mononuclear cells and intestinal mucosa tissue using mass cytometry to evaluate immune cell types, which revealed global immune dysregulation characteristics underlying necrotizing enterocolitis.

Results

Compared with controls, natural killer cells display signs of heightened activation and increased cytotoxic potential in the peripheral blood and mucosa of patients with necrotizing enterocolitis. Furthermore, CD4+ T effector memory cells, non-classical monocytes, active dendritic cells, and neutrophils were specifically enriched in the mucosa, suggesting trafficking from the periphery to areas of inflammation. Moreover, we mapped the systemic and local distinct immune signatures suggesting patterns of cell localization in necrotizing enterocolitis.

Conclusion

We used mass cytometry time-of-flight technology to identify immune cell populations specific to the peripheral blood and intestinal mucosa tissue from patients with necrotizing enterocolitis and controls. This information might be used to develop precise diagnosis and therapies that target specific cell populations in patients with necrotizing enterocolitis.

Benefits of routine probiotic supplementation in preterm infants

AIM

We introduced routine probiotic supplementation (RPS) of preterm infants in June 2012. We previously reported that RPS reduced the incidence of necrotising enterocolitis (NEC) and mortality in such infants. In this study, we assessed if the benefits of RPS were sustained for infants in the current era.

METHOD

We compared the outcomes of preterm infants in recent epoch 3 (RPS, 1st June 2014 to 31st December 2019) versus epoch 2 (RPS, 1st June 2012 to 31st May 2014) and epoch 1 (no RPS, 1st December 2008 to 30th November 2010). Multiple logistic and Cox regression models were used to compare the outcomes.

RESULTS

There were 645 infants in epoch 1, 712 in epoch 2 and 1715 in epoch 3. Age at full feeds was significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants <28 weeks of gestation. NEC and late-onset sepsis (LOS) were significantly lower in epoch 3 vs. 1 in infants <28 weeks. LOS and age at full feeds were significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants with gestation 28 to 32 weeks.

CONCLUSION

The benefits associated with RPS were sustained during epoch 3.

Outcome Reporting in Interventional Necrotizing Enterocolitis Studies: A Systematic Review

BACKGROUND

Despite an increasing necrotizing enterocolitis (NEC) incidence, treatment strategies have failed to make major advancements towards improved NEC outcomes. Heterogeneity in outcome reporting and a lack of treatment efficacy studies potentially hamper these advancements. We aimed to analyze outcome reporting in recent interventional NEC studies.

METHODS

We performed a systematic review identifying interventional studies on NEC between 1st of January 2016 and 1st of June 2023 in MEDLINE, Embase, CENTRAL and Cochrane reviews. Systematic reviews, clinical trials and change-in-practice cohort studies reporting any therapeutic intervention for NEC patients (Bell's stage ≥ IIa) were eligible. We excluded studies on NEC diagnostics or prevention and non-English publications. Outcomes were categorized into five core areas and presented descriptively. The review was registered with PROSPERO (CRD42022302712).

RESULTS

Out of 1.642 screened records, 65 were eligible for full-text review and 15 were finally included for data extraction. Median number of reported outcomes per article was six (range 1-19). We identified 66 unique outcomes, which were mapped to 53 outcome terms. Thirty-four out of the 53 of the outcome terms (64%) were only reported in a single article. Mortality was the most reported outcome (11/15 articles, 73%). Core area 'Adverse outcomes' contained the most outcome terms (n = 19), whereas 'Life impact' contained the least outcome terms (n = 4) and was represented in 3 articles (20%).

CONCLUSIONS

Considerable heterogeneity in outcome reporting and a paucity of outcomes concerning 'Life impact' exist in interventional NEC studies. Development of a NEC core outcome set may improve consistency and patient-relevance in outcome reporting.

STUDY TYPE

Systematic Review and Meta-Analyses.

LEVEL OF EVIDENCE

III.

Limosilactobacillus reuteri DSM 17938 as a probiotic in preterm infants: An updated systematic review with meta-analysis and trial sequential analysis

BACKGROUND

Our previous strain-specific systematic review (SR) showed that Lactobacillus reuteri (LR) DSM 17938 reduces necrotizing enterocolitis (NEC), late-onset sepsis (LOS), and time to full feeds (TFF) in preterm infants. Considering progress in the field over the past 6 years, we aimed to update our SR.

METHODS

SR of randomized controlled trials (RCTs) and non-RCTs was conducted. MEDLINE, Embase, Emcare, Cochrane CENTRAL, and gray literature were searched in June 2023. Primary outcomes were TFF, NEC stage ≥II, LOS, and all-cause mortality. Meta-analysis was performed using random-effects model. Certainty of evidence (CoE) was summarized using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) guidelines. Trial sequential analysis (TSA) was applied for outcome of NEC in RCTs.

RESULTS

Twelve RCTs (n = 2284) and four non-RCTs (n = 1616) were included. Six RCTs and three non-RCTs were new. Meta-analysis of RCTs showed LR significantly reduced TFF (mean difference, -2.70 [95% CI, -4.90 to -1.31] days; P = 0.0001), NEC stage ≥II (risk ratio [RR], 0.57 [95% CI, 0.37-0.87]; P = 0.009; eight RCTs), and LOS (RR, 0.72 [95% CI, 0.54-0.97]; P = 0.03); but not mortality (RR, 0.76 [95% CI, 0.54-1.06]; P = 0.10). TSA showed diversity-adjusted required information size (DARIS) as 3624 for NEC. Overall CoE was "very low." Meta-analysis of non-RCTs showed LR reduced NEC (odds ratio, 0.34 [95% CI, 0.15-0.77]; P = 0.01) but not LOS. LR had no adverse effects.

CONCLUSIONS

Very low CoE suggests that LR DSM 17938 may reduce NEC and LOS and shorten TFF in preterm infants. Additional RCTs are required to confirm our findings.

New insights into intestinal macrophages in necrotizing enterocolitis: the multi-functional role and promising therapeutic application

Necrotizing enterocolitis (NEC) is an inflammatory intestinal disease that profoundly affects preterm infants. Currently, the pathogenesis of NEC remains controversial, resulting in limited treatment strategies. The preterm infants are thought to be susceptible to gut inflammatory disorders because of their immature immune system. In early life, intestinal macrophages (IMφs), crucial components of innate immunity, demonstrate functional plasticity and diversity in intestinal development, resistance to pathogens, maintenance of the intestinal barrier, and regulation of gut microbiota. When the stimulations of environmental, dietary, and bacterial factors interrupt the homeostatic processes of IMφs, they will lead to intestinal disease, such as NEC. This review focuses on the IMφs related pathogenesis in NEC, discusses the multi-functional roles and relevant molecular mechanisms of IMφs in preterm infants, and explores promising therapeutic application for NEC.

Role of the gut-microbiota-metabolite-brain axis in the pathogenesis of preterm brain injury

Brain injury, a common complication in preterm infants, includes the destruction of the key structural and functional connections of the brain and causes neurodevelopmental disorders; it has high morbidity and mortality rates. The exact mechanism underlying brain injury in preterm infants is unclear. Intestinal flora plays a vital role in brain development and the maturation of the immune system in infants; however, detailed understanding of the gut microbiota-metabolite-brain axis in preterm infants is lacking. In this review, we summarise the key mechanisms by which the intestinal microbiota contribute to neurodevelopment and brain injury in preterm infants, with special emphasis on the influence of microorganisms and their metabolites on the regulation of neurocognitive development and neurodevelopmental risks related to preterm birth, infection and neonatal necrotising enterocolitis (NEC). This review provides support for the development and application of novel therapeutic strategies, including probiotics, prebiotics, synbiotics, and faecal bacteria transplantation targeting at brain injury in preterm infants.

Prediction of GutCheck NEC and Its Relation to Severity of Illness and Measures of Deterioration in Necrotizing Enterocolitis

BACKGROUND

Necrotizing enterocolitis (NEC) risk has been shown to arise from multiple sources and risk awareness may be supported using bedside tools.

PURPOSE

The purpose of this research was to examine the extent to which GutCheck NEC was associated with scores for clinical deterioration, severity of illness, and clinical outcome, and further to examine how scores might improve NEC prediction.

METHODS

A retrospective, correlational case-control study with infant data from 3 affiliated neonatal intensive care units was conducted.

RESULTS

Of 132 infants (44 cases, 88 controls), most were 28 weeks of gestation at birth and less (74%). Median age at NEC onset was 18 days (range: 6-34 days), with two-thirds diagnosed before 21 days. At 68 hours of life, higher GutCheck NEC scores were associated with NEC requiring surgery or resulting in death (relative risk ratio [RRR] = 1.06, P = .036), associations that persisted at 24 hours prior to diagnosis (RRR = 1.05, P = .046), and at the time of diagnosis (RRR = 1.05, P = .022) but showed no associations for medical NEC. GutCheck NEC scores were significantly correlated with pediatric early warning scores (PEWS) ( r > 0.30; P < .005) and SNAPPE-II scores ( r > 0.44, P < .0001). Increasing numbers of clinical signs and symptoms were positively associated with GutCheck NEC and PEWS at the time of diagnosis ( r = 0.19, P = .026; and r = 0.25, P = .005, respectively).

IMPLICATIONS FOR PRACTICE AND RESEARCH

GutCheck NEC provides structure to streamline assessment and communication about NEC risk. Yet, it is not intended to be diagnostic. Research is needed on how GutCheck NEC impacts timely recognition and treatment.

Recent advances in our understanding of NEC diagnosis, prognosis and surgical approach

Necrotising enterocolitis (NEC) remains a devasting condition that has seen limited improvement in outcomes in recent years. The incidence of the disease is increasing as more extremely premature infants survive. NEC is responsible for 1 in 10 neonatal deaths and up to 61% of survivors have significant neurodevelopmental delay. The aim of this review is to highlight recent advances in diagnosis, prognosis and surgical approach in this condition. Many recent studies have reported novel methods of diagnosis of NEC with the aim of earlier and more accurate identification. These include imaging and machine learning techniques. Prognostication of NEC is particularly important to allow earlier escalation of therapy. Around 25% of infants with NEC will require surgery and recent data has shown that time from disease onset to surgery is greater in infants whose indication for surgery is failed medical management, rather than pneumoperitoneum. This indication was also associated with worse outcomes compared to pneumoperitoneum. Ongoing research has highlighted several new methods of disease prognostication which includes differentiating surgical from medical NEC. Finally, recent randomised controlled trials in surgical technique are discussed along with the implications of these for practice. Further, high quality research utilising multi-centre collaborations and high fidelity data from electronic patient records is needed to address the issues discussed and ultimately improve outcomes in NEC.