Necrotizing enterocolitis (NEC) is a microbiota- and feeding-related gut inflammatory disease in preterm infants. The standard of care (SOC) treatment for suspected NEC is antibiotic treatment and reduced enteral feeding, but how SOC treatment mitigates NEC remains unclear. We explored whether SOC treatment alone or combined with an anti-inflammatory protein (inter-alpha inhibitor protein, IAIP) supplementation improves outcomes in a preterm piglet model of formula-induced NEC. Seventy-one cesarean-delivered preterm piglets were initially fed formula, developing NEC symptoms by day 3, and then randomized into CON (continued feeding) or SOC groups (feeding cessation and antibiotics), each with or without human IAIP (2×2 factorial design). By day 5, IAIP treatment did not significantly influence outcomes, whereas SOC treatment effectively reduced NEC lesions, diarrhea, and bloody stools. Notably, SOC treatment improved gut morphology and function, dampened gut inflammatory responses, altered the colonic microbiota composition, and modulated systemic immune responses. Plasma proteomic analysis revealed the effects of SOC treatment on organ development and systemic inflammatory responses. Collectively, these findings suggest that SOC treatment significantly prevents NEC progression in preterm piglets via effects on gut structure, function, and microbiota, as well as systemic immune and inflammatory responses. Timely feeding cessation and antibiotics are critical factors in preventing NEC progression in preterm infants, while the benefits of additional human IAIP treatment remain to be established.

BACKGROUND: To construct a nomogram for predicting necrotizing enterocolitis (NEC) in preterm infants.
METHODS: A total of 4,724 preterm infants who were admitted into 8 hospitals between April 2019 and September 2020 were initially enrolled this retrospective multicenter cohort study. Finally, 1,092 eligible cases were divided into training set and test set based on a 7:3 ratio. A univariate logistic regression analysis was performed to compare the variables between the two groups. Stepwise backward regression, LASSO regression, and Boruta feature selection were utilized in the multivariate analysis to identify independent risk factors. Then a nomogram model was constructed based on the identified risk factors.
RESULTS: Risk factors for NEC included gestational diabetes mellitus, gestational age, small for gestational age, patent ductus arteriosus, septicemia, red blood cell transfusion, intravenous immunoglobulin, severe feeding intolerance, and absence of breastfeeding. The nomogram model developed based on these factors showed well discriminative ability. Calibration and decision curve analysis curves confirmed the good consistency and clinical utility of the model.
CONCLUSIONS: We developed a nomogram model with strong discriminative ability, consistency, and clinical utility for predicting NEC. This model could be valuable for the early prediction of preterm infants at risk of developing NEC.

Necrotizing enterocolitis (NEC) is a severe intestinal disease of very preterm infants with mother\'s own milk (MOM) providing protection, but the contribution of the MOM microbiota to NEC risk has not been explored. Here, we analyze MOM of 110 preterm infants (48 NEC, 62 control) in a cross-sectional study. Breast milk contains viable bacteria, but there is no significant difference in MOM microbiota between NEC and controls. Integrative analysis between MOM microbiota, human milk oligosaccharides (HMOs), and the infant gut microbiota shows positive correlations only between Acinetobacter in the infant gut and Acinetobacter and Staphylococcus in MOM. This study suggests that NEC protection from MOM is not modulated through the MOM microbiota. Thus, \"\'restoring\" the MOM microbiota in donor human milk is unlikely to reduce NEC, and emphasis should instead focus on increasing fresh maternal human milk intake and researching different therapies for NEC prevention.

Aberrant preterm infant gut microbiota assembly predisposes to early-life disorders and persistent health problems. Here, we characterize gut microbiome dynamics over the first 3 months of life in 236 preterm infants hospitalized in three neonatal intensive care units using shotgun metagenomics of 2,512 stools and metatranscriptomics of 1,381 stools. Strain tracking, taxonomic and functional profiling, and comprehensive clinical metadata identify Enterobacteriaceae, enterococci, and staphylococci as primarily exploiting available niches to populate the gut microbiome. Clostridioides difficile lineages persist between individuals in single centers, and Staphylococcus epidermidis lineages persist within and, unexpectedly, between centers. Collectively, antibiotic and non-antibiotic medications influence gut microbiome composition to greater extents than maternal or baseline variables. Finally, we identify a persistent low-diversity gut microbiome in neonates who develop necrotizing enterocolitis after day of life 40. Overall, we comprehensively describe gut microbiome dynamics in response to medical interventions in preterm, hospitalized neonates.

BACKGROUND: Surgeons often encounter patients with intestinal failure due to inadequate intestinal length (\"short bowel syndrome\"/SBS). Treatment in these patients remains challenging and the process of physiologic adaptation may take years to complete, which frequently requires parenteral nutrition. We propose a proof-of-concept mechanical bowel elongation approach using a self-expanding prototype of an intestinal expansion sleeve (IES) for use in SBS to accelerate the adaptation process.
METHODS: IESs were deployed in the small intestines of Sprague Dawley rats. Mechanical characterization of these prototypes was performed. IES length-tension relationships and post-implant bowel expansion were measured ex vivo. Bowel histology before and after implantation was evaluated.
RESULTS: IES mechanical studies demonstrated decreasing expansive force with elongation. The deployment of IES devices produced an immediate 21 ± 8% increase in bowel length (p < 0.001, n = 11). Mechanical load testing data showed that the IESs expressed maximum expansive forces at 50% compression of the initial pre-contracted length. The small-intestine failure load in the rats was 1.88 ± 21 N. Intestinal histology post deployment of the IES showed significant expansive changes compared to unstretched bowel tissue.
CONCLUSIONS: IES devices were scalable to the rat intestinal model in our study. The failure load of the rat small intestine was many times higher than the force exerted by the contraction of the IES. Histology demonstrated preservation of intestinal structure with some mucosal erosion. Future in vivo rat studies on distraction enterogenesis with this IES should help to define this organogenesis phenomenon.

OBJECTIVE: The analysis of abdominal radiography is essential for the diagnosis and management of necrotizing enterocolitis (NEC) in newborns (NB). Studies, however, show a lack of agreement among physicians in the interpretation of images. This study aims to evaluate the agreement in the radiological interpretation of the NEC between examiners from different specialties (interexaminer analysis) and between the same examiner at different times (intraexaminer analysis).
METHODS: Cross-sectional study for concordance analysis using plain radiographs of the abdomen of NB with suspected or confirmed NEC. The study included two neonatologists (Neo), two surgeons (SU), and two radiologists (RD). The participants filled out a form with questions about the radiographic findings; regarding the presence of intestinal loop distension, the specialists answered subjectively (yes or no) and objectively (calculation of the ratio between loop diameter and lumbar vertebrae measurements). Kappa coefficients were calculated for agreement analysis.
RESULTS: A total of 90 radiological images were analyzed. For the interexaminer evaluation, the agreement was low (kappa<0.4) in 30 % of the answers (Neo versus SU), 38 % (Neo versus RD), and 46 % (SU versus RD). In the intraexaminer evaluation, the neonatologist and the surgeon presented substantial or almost perfect agreement in 92 % of the answers, and the radiologist in 77 %. In the evaluation of intestinal loop distention, the greatest agreement between the specialties occurred when done objectively.
CONCLUSIONS: The results confirmed the low intra- and interexaminer agreement in the radiological analysis of the NEC, reinforcing the importance of standardizing the methods of radiological interpretation of the disease.

BACKGROUND: Although pneumoperitoneum from necrotizing enterocolitis or spontaneous intestinal perforation is a surgical emergency, risk stratification to determine which neonates benefit from initial peritoneal drainage (PD) is lacking.
METHODS: Using a single-center retrospective review of very low birth weight neonates under 1500 g who underwent PD for pneumoperitoneum (January 2015 to December 2023) from necrotizing enterocolitis or spontaneous intestinal perforation, two cohorts were created: drain \"responders\" (patients managed definitively with PD; includes placement of a second drain) and \"nonresponders\" (patients who underwent subsequent laparotomy or died after PD). Antenatal/postnatal characteristics, periprocedural clinical data, and hospital outcomes were compared between responders and nonresponders using Student\'s t-test, chi-squared test, or Kruskal-Wallis test as appropriate, with P < 0.05 considered significant.
RESULTS: Fifty-six neonates were included: 31 (55%) drain responders and 25 (45%) nonresponders. Birth weight, gestational age, sex, ethnicity, use of postnatal steroids, and enteral feeds were similar between the cohorts. Nonresponders had higher base deficits (-3.4 versus -5.0, P = 0.032) and FiO2 (0.25 versus 0.52, P = 0.001) after drain placement. Drain responders had significantly shorter lengths of stay (89 versus 148 days, P = 0.014) and lower mortality (6.4% versus 56%, P < 0.001). A subgroup analysis of the nonresponders showed no differences in birth weight, vasopressor requirement, FiO2, or postdrain base deficit between nonresponders who had a drain alone versus laparotomy following drain placement.
CONCLUSIONS: PD remains a viable initial therapy for pneumoperitoneum in premature very low birth weight neonates (< 1500 g), demonstrating clinical response in more than half. Ongoing clinical assessment and judgment is imperative after drain placement to ensure continued clinical improvement.

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.

Purpose: Weight thresholds have historically determined timing of enterostomy closure (EC) in premature neonates. Recent evidence suggests that neonates less than 2 kg (L2K) can safely undergo EC. We evaluate our single-center experience with performing EC in preterm neonates at L2K versus greater than 2 kg (G2K) at time of EC. Methods: A retrospective review of neonates who underwent EC from January 2018 to 2020 was performed. Neonates who were greater than 90 days at initial operation were excluded. Demographics, clinical characteristics including gestational age (GA) and birth weight (BW), operative reports, and outcomes were reviewed. We compared 30-day complications between neonates who underwent EC at L2K and G2K. We also compared time to full feeds (FF) and postoperative length of stay (LOS). Results: Twenty-four neonates were included: 11 L2K and 13 G2K. The median GA and BW was 25.9 weeks (IQR 2.89) and 805 g (IQR 327), respectively. The most common intraoperative diagnosis during index operation was spontaneous perforation (70%), followed by necrotizing enterocolitis (8.69%). There were no significant differences in GA, BW, or diagnosis, between the L2K versus G2K cohort. We found no difference in complication rates, time to FF (12 days versus 10 days, P = .89), or postoperative LOS (31 days versus 36.5 days, P = .76) between patients who underwent EC at L2K versus G2K, respectively. Conclusion: Although weight gain may be an important indicator of perioperative nutrition status, this study shows that weight alone should not preclude otherwise appropriate patients from undergoing EC.

UNASSIGNED: To explore risk factors for Stage-III necrotizing enterocolitis (NEC-III) in preterm neonates.
UNASSIGNED: This was a retrospective case-control study of neonates born <33 weeks gestational age (GA) who were admitted to a tertiary neonatal intensive care unit, between 2015 and 2018. NEC-III cases were compared with Stage-II NEC (NEC-II) and non-NEC controls. Two to four non-NEC controls were matched by GA ± 1 week and date of birth ± 3 months, to one NEC-III case. Univariate and multivariate analyses were used to examine risk factors for NEC-III.
UNASSIGNED: Of 1360 neonates born <33 weeks, 71 (5.2%) had NEC-II and above, with 46% being NEC-III. Mean age of onset of NEC-III was 13.7 days versus 23.9 days for NEC-II (p = 0.01). Neonates with NEC-III were of lower GA (NEC-III 25.4 weeks, NEC-II 27.3 weeks, and non-NEC 26 weeks; p = 0.0008) and had higher Score for Neonatal Acute Physiology Perinatal Extension-II scores (NEC-III 47.5, NEC-II 28.4 and non-NEC 37, p = 0.003). Multivariate analysis showed duration of umbilical arterial catheter (UAC) >5 days was significantly associated with the development of NEC-III with adjusted odds ratio (AOR) 3.8; 95% confidence interval (CI) (1.05-13.66) for NEC-III versus non-NEC and AOR 5.57; 95% CI (1.65-18.73), p = 0.006 for NEC-III versus NEC-II. Rupture of membranes (ROM) >1 week was associated with NEC-III (AOR 6.93; 95% CI [1.56-30.69] vs. non-NEC and AOR 11.74; 95% CI [1.14-120.34] vs. NEC-II).
UNASSIGNED: The increased association of NEC-III with duration of UAC and ROM could be further examined in prospective studies, and an upper limit for UAC duration could be considered in NEC prevention bundles.