Can we cut the incidence of necrotizing enterocolitis in half--today?

Is choline deficiency an unrecognized factor in necrotizing enterocolitis of preterm infants?

We undertook this review to determine if it is plausible that choline or phosphatidylcholine (PC) deficiency is a factor in necrotizing enterocolitis (NEC) after two clinical trials found a dramatic and unexpected reduction in NEC in an experimental group provided higher PC compared to a control group. Sources and amounts of choline/PC for preterm infants are compared to the choline status of preterm infants at birth and following conventional nutritional management. The roles of choline/PC in intestinal structure, mucus, mesenteric blood flow, and the cholinergic anti-inflammatory system are summarized. Low choline/PC status is linked to prematurity/immaturity, parenteral and enteral feeding, microbial dysbiosis and hypoxia/ischemia, factors long associated with the risk of developing NEC. We conclude that low choline status exists in preterm infants provided conventional parenteral and enteral nutritional management, and that it is plausible low choline/PC status adversely affects intestinal function to set up the vicious cycle of inflammation, loss of intestinal barrier function and worsening tissue hypoxia that occurs with NEC. In conclusion, this review supports the need for randomized clinical trials to test the hypothesis that additional choline or PC provided parenterally or enterally can reduce the incidence of NEC in preterm infants. IMPACT STATEMENT: Low choline status in preterm infants who are managed by conventional nutrition is plausibly linked to the risk of developing necrotizing enterocolitis.

Cannabidiol decreases histological intestinal injury in a neonatal experimental model of necrotizing enterocolitis

BACKGROUND

Necrotizing enterocolitis (NEC) is a severe inflammatory bowel disease in neonates. Our group has developed an experimental model of NEC, with an effectiveness of 73%. Cannabidiol (CBD) is an innovative treatment for neonatal cerebral hypoxic-ischemic pathologies due to its neuroprotective effect, as a potent anti-inflammatory and reducing oxidative stress substance. Our aim was to evaluate the effect of CBD on intestinal lesions in an experimental model of NEC.

RESULTS

Mortality and intestinal histological damage was significantly lower in the CBD group compared to the rest (p<0.05), establishing CBD as a protective factor against the development of NEC (OR=0.0255; 95% CI=0.0015-0.4460). At IHQ level (TUNEL technique), a lower cell death rate was also observed in the CBD group compared to the VEH group (p<0.05).

CONCLUSIONS

In our experimental model, intraperitoneal CBD acts as a protective factor against NEC, resulting in less histological damage and a lower rate of intestinal cell death.

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.

Measuring gut perfusion and blood flow in neonates using ultrasound Doppler of the superior mesenteric artery: a narrative review

The gut is a relatively silent organ in utero but takes on a major role after birth for the absorption and digestion of feed for adequate nutrition and growth. The neonatal circulation undergoes a transition period after birth, and gut perfusion increases rapidly to satisfy the oxygen demand and consumption. If this process is compromised at any stage, preterm and fetal growth restricted infants are at particular risk of gut tissue injury secondary to hypoxia, leading to necrotizing enterocolitis. Feeding can also be a challenge in these high-risk groups due to gut dysmotility. Superior mesenteric artery (SMA) Doppler is a safe, bedside investigation that could rapidly aid clinicians with feeding strategies and in monitoring high-risk infants. This article aims to establish normal patterns of gut blood flow velocity in neonates using SMA Doppler and reviews how it might be used clinically in pathologic states.

Comparison of twelve human milk oligosaccharides in mature milk from different areas in China in the Chinese Human Milk Project (CHMP) study

Human milk oligosaccharides (HMOs) act as a vital role in the development of infant's gut microbiome and immune function. This study aimed to measure 12 oligosaccharides in milk from Chinese donors (n = 203), and evaluated the influences of multiple factors on the HMOs profiles. The results indicated that concentrations of 6'-sialyllactose were the highest among 12 oligosaccharides (2.31 ± 0.81 g/L). HMOs concentrations varied depending on geographical location. Latitude was observed to be related to concentrations of Lacto-N-neohexaose, lacto-N-fucopentaose III, 3'-sialyllactose (r = -0.67, r = +0.63 and r = +0.50, respectively). Environmental factors like seasons correlated with lacto-N-difucohexaose Ⅱ, Lacto-N-neohexaose and 2'-fucosyllactose (r = -0.47, r = -0.4, r = -0.35, respectively). Several HMOs concentrations were correlated with maternal diet. As a consequence, the HMOs profiles measured were influenced by geographical, environmental, maternal anthropometric as well as dietary factors.

Engaging Parents of Fragile Infants in the Design and Appraisal of Health Literature: An Español Toolkit for Necrotizing Enterocolitis

WHAT WAS OBSERVED OR INVESTIGATED

The increased morbidity of diverse infants is unacceptable, and methods to reduce necrotizing enterocolitis (NEC) in their communities are needed. This article discusses the importance of the Español toolkit; provides a backstory of how the Español toolkit came about and how it was verified and validated; and concludes with impressions from involving parents in the research process.

SUBJECTS AND METHODS

After research evidence was translated from English into Spanish, a cross-sectional exploratory, descriptive, mixed-methods study was conducted, guided by the knowledge translation into practice (Translating Research Into Practice [TRIP]) framework. Twenty bilingual English-Spanish parents of fragile infants evaluated the NEC-Zero Español toolkit from a single neonatal intensive care unit.

RESULTS AND CONCLUSIONS

The NEC-Zero Español toolkit was found to be easy-to-use and useful and provided information that can be used to augment information sharing. Having access to health information offers a meaningful way to start a conversation and may even impact positive behaviors such as breastfeeding promotion. To lessen Spanish speakers' linguistic barriers, providing materials in Spanish can help meet their information needs and initiate conversations with healthcare providers. This is particularly important because Hispanic infants are at high risk for NEC.

Clinical characteristics of neonatal fulminant necrotizing enterocolitis in a tertiary Children's hospital in the last 10 years

The aim of this retrospective study was to explore the risk factors and clinical characteristics related to neonatal fulminant necrotizing enterocolitis (NEC). From 1 November 2007 to 31 October 2017, 352 neonates who were diagnosed with NEC (Bell stage ≥ΠB) and admitted to the Children’s Hospital of Chongqing Medical University were enrolled. Among these patients, 112 (31.82%) cases fulfilled the definition of fulminant NEC, and 62.5% (70/112) of fulminant cases presented a poor prognosis. All the survivors in the fulminant NEC group underwent surgery. Those in the fulminant NEC group were more likely to have the following clinical features: sepsis preceding NEC (P<0.001), abdominal distention (P<0.001), bowel sound disappearance (P = 0.001), leukopenia or neutropenia (P<0.001), C-reactive protein (CRP) <10 mg/L (P = 0.003), procalcitonin (PCT) < 2 μg/L (P<0.001), pH ≤7.2 (P<0.001), and radiographic evidence of pneumoperitoneum (P<0.001) or seroperitoneum on ultrasonography (P = 0.017). In conclusion, fulminant NEC is characterized by urgent onset and prompt deterioration, potentially resulting in death. The lack of unique characteristics makes it difficult to recognize by medical caregivers. Close observation, early detection and timely surgical intervention may improve the prognosis.

Modifiable Risk Factors in Necrotizing Enterocolitis

Multicenter groups have reported reductions in the incidence of necrotizing enterocolitis (NEC) among preterm infants over the past 2 decades. These large-scale prevalence studies have coincided with reports from multicenter consortia and single centers of modifications in practice using quality-improvement techniques aimed at either reducing NEC risk specifically or reducing risk of mortality and multiple morbidities associated with extreme prematurity. The modifications in practice have been based on mechanistic studies, epidemiologic association data, and clinical trials. Recent reports from centers modifying practice to reduce NEC are reviewed and select modified/modifiable practices discussed.

New Nutritional and Therapeutical Strategies of NEC

Necrotizing enterocolitis (NEC) is an acquired severe disease of the digestive system affecting mostly premature babies, possibly fatal and frequently associated to systemic complications. Because of the severity of this condition and the possible long-term consequences on the child's development, many studies have aimed at preventing the occurrence of the primary events at the level of the bowel wall (ischemia and necrosis followed by sepsis) by modifying or manipulating the diet (breast milk versus formula) and/or the feeding pattern (time for initiation after birth, continuous versus bolus feeding, modulation of intake according clinical events). Feeding have been investigated so far in order to prevent NEC. However, currently well-established and shared clinical nutritional practices are not available in preventing NEC. Nutritional and surgical treatments of NEC are instead well defined. In selected cases surgery is a therapeutic option of NEC, requiring sometimes partial intestinal resection responsible for short bowel syndrome. In this paper we will investigate the available options for treating NEC according to the Walsh and Kliegman classification, focusing on feeding practices in managing short bowel syndrome that can complicate NEC. We will also analyze the proposed ways of preventing NEC.

Standardized Feeding Protocols to Reduce Risk of Necrotizing Enterocolitis in Fragile Infants Born Premature or with Congenital Heart Disease: Implementation Science Needed

Although a unit-adopted standardized feeding protocol (SFP) for neonates is standard of care, implementation strategies for SFPs vary across neonatal and pediatric intensive care. Besides improving growth and reducing feeding interruptions, SFPs reduce risk for necrotizing enterocolitis in infants with heart disease or born premature. The purpose of this article is to bridge the gap between recommended and actual care using SFPs.

Comparative Effectiveness of Prophylactic Therapies for Necrotizing Enterocolitis in Preterm Infants: Protocol for a Network Meta-analysis of Randomized Trials

Necrotizing enterocolitis (NEC) is a common and devastating disease with high morbidity and mortality in premature infants. Current literature on the prevention of NEC has limitations including lack of direct and indirect comparisons of available therapies. We will search MEDLINE, EMBASE, Science Citation Index Expanded, Social Sciences Citation Index, CINAHL, Scopus, ProQuest Dissertations and Theses database, and grey literature sources to identify eligible trials evaluating NEC preventive therapies. Eligible studies will (1) enroll preterm (gestational age <37 weeks) and/or low birth weight (birth weight <2500 g) infants, (2) randomize infants to any preventive intervention or a placebo, or alternative active or nonactive intervention. Our outcomes of interest are severe NEC (stage II or more, based on Bell's criteria), all-cause mortality, NEC-related mortality, late-onset sepsis, duration of hospitalization, weight gain, time to establish full enteral feeds, and treatment-related adverse events. Two reviewers will independently screen trials for eligibility, assess risk of bias, and extract data. All discrepancies will be resolved by discussion. We will specify a priori explanations for heterogeneity between studies. For available comparisons between treatment and no treatment, and direct comparisons of treatments, we will conduct conventional meta-analysis using a random effects model. We will conduct a network meta-analysis using a random effects model within the Bayesian framework using Markov chain Monte Carlo methods to assess relative effects of eligible interventions. We will assess the certainty in direct, indirect, and network estimates using the Grading of Recommendations Assessment, Development and Evaluation approach.

Maternal pregnancy-induced hypertension increases subsequent neonatal necrotizing enterocolitis risk: A nationwide population-based retrospective cohort study in Taiwan

The utero-placental ischemia induced by pregnancy-induced hypertension (PIH) could lead to fetal hypoxia and proinflammatory cytokine release, which are associated with the development of neonatal necrotizing enterocolitis (NEC). However, a few studies have investigated the relationship between PIH and neonatal NEC and have produced controversial results. Therefore, we attempted to assess the relationship between PIH and the subsequent neonatal NEC risk and identify predictive risk factors.Patients with newly diagnosed PIH were recruited from the Taiwan National Health Insurance Research Database (NHIRD). For each participant, 4 age- and delivery-year-matched participants without PIH were randomly selected. A multivariable logistic regression was performed for the identification of the predictive risk factors for neonatal NEC.Among the 23.3 million individuals registered in the NHIRD, 29,013 patients with PIH and 116,052 matched controls were identified. For the multivariable analysis, maternal PIH was associated with an increased risk of subsequent neonatal NEC development (odds ratio [OR] 1.86, 95% confidence interval [CI] 1.08-3.21, P = .026). Furthermore, single parity (OR 2.06, 95% CI 1.12-3.77, P = .019), preterm birth (OR 5.97, 95% CI 3.49-10.20, P < .001), multiple gestations (OR 2.25, 95% CI 1.22-4.14, P = .010), and intrauterine growth restriction (IUGR) (OR 3.59, 95% CI 2.06-6.24, P < .001) were independent risk factors for the development of subsequent neonatal NEC.Maternal PIH increases the risk for developing neonatal NEC. Furthermore, primiparity, preterm birth, multiple gestations, and IUGR were independent risk factors for neonatal NEC.

Protective effect of Lactobacillus reuteri DSM 17938 against experimental necrotizing enterocolitis is mediated by Toll-like receptor 2

Lactobacillus reuteri DSM 17938 (LR 17938) has been shown to reduce the incidence and severity of necrotizing enterocolitis (NEC). It is unclear if preventing NEC by LR 17938 is mediated by Toll-like receptor 2 (TLR2), which is known to mediate proinflammatory responses to bacterial cell wall components. NEC was induced in newborn TLR2^-/- or wild-type (WT) mice by the combination of gavage-feeding cow milk-based formula and exposure to hypoxia and cold stress. Treatment groups were administered formula supplemented with LR 17938 or placebo (deMan-Rogosa-Sharpe media). We observed that LR 17938 significantly reduced the incidence of NEC and reduced the percentage of activated effector CD4⁺T cells, while increasing Foxp3⁺ regulatory T cells in the intestinal mucosa of WT mice with NEC, but not in TLR2^-/- mice. Dendritic cell (DC) activation by LR 17938 was mediated by TLR2. The percentage of tolerogenic DC in the intestine of WT mice was increased by LR 17938 treatment during NEC, a finding not observed in TLR2^-/- mice. Furthermore, gut levels of proinflammatory cytokines IL-1β and IFN-γ were decreased after treatment with LR 17938 in WT mice but not in TLR2^-/- mice. In conclusion, the combined in vivo and in vitro findings suggest that TLR2 receptors are involved in DC recognition and DC-priming of T cells to protect against NEC after oral administration of LR 17938. Our studies further clarify a major mechanism of probiotic LR 17938 action in preventing NEC by showing that neonatal immune modulation of LR 17938 is mediated by a mechanism requiring TLR2. NEW & NOTEWORTHY Lactobacillus reuteri DSM 17938 (LR 17938) has been shown to protect against necrotizing enterocolitis (NEC) in neonates and in neonatal animal models. The role of Toll-like receptor 2 (TLR2) as a sensor for gram-positive probiotics, activating downstream anti-inflammatory responses is unclear. Our current studies examined TLR2 ^-/- mice subjected to experimental NEC and demonstrated that the anti-inflammatory effects of LR 17938 are mediated via a mechanism requiring TLR2.

Human and Bovine Colostrum for Prevention of Necrotizing Enterocolitis: A Meta-analysis

CONTEXT

Human and bovine colostrum (HBC) administration has been linked to beneficial effects on morbidity and mortality associated with necrotizing enterocolitis (NEC).

OBJECTIVES

To determine the effectiveness and safety of HBC for reducing NEC, mortality, sepsis, time to full-feed and feeding intolerance in preterm infants.

DATA SOURCES

We conducted searches through Medline, Embase, Cumulative Index of Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, and gray literature.

STUDY SELECTION

Randomized controlled trials comparing human or bovine colostrum to placebo.

DATA EXTRACTION

Two reviewers independently did screening, review, and extraction.

RESULTS

Eight studies (385 infants) proved eligible. In comparison with placebo, HBC revealed no effect on the incidence of severe NEC (relative risk [RR]: 0.99; 95% confidence interval [CI] 0.48 to 2.02, I² = 2.2%; moderate certainty of evidence), all-cause mortality (RR: 0.88; 95% CI 0.39 to 1.82, I² = 0%; moderate certainty), culture-proven sepsis (RR: 0.78; 95% CI 0.53 to 1.14, I² = 0%; moderate certainty), and feed intolerance (RR: 0.97; 95% CI 0.37 to 2.56, I² = 55%; low certainty). HBC revealed a significant effect on reducing the mean days to reach full enteral feed (mean difference: -3.55; 95% CI 0.33 to 6.77, I² = 41.1%; moderate certainty). The indirect comparison of bovine versus human colostrum revealed no difference in any outcome.

LIMITATIONS

The number of patients was modest, whereas the number of NEC-related events was low.

CONCLUSIONS

Bovine or human colostrum has no effect on severe NEC, mortality, culture-proven sepsis, feed intolerance, or length of stay. Additional research focused on the impact on enteral feeding may be needed to confirm the findings on this outcome.

A quality improvement initiative to reduce necrotizing enterocolitis across hospital systems

OBJECTIVE

Necrotizing enterocolitis (NEC) is a devastating intestinal disease in premature infants. Local rates of NEC were unacceptably high. We hypothesized that utilizing quality improvement methodology to standardize care and apply evidence-based practices would reduce our rate of NEC.

STUDY DESIGN

A multidisciplinary team used the model for improvement to prioritize interventions. Three neonatal intensive care units (NICUs) developed a standardized feeding protocol for very low birth weight (VLBW) infants, and employed strategies to increase the use of human milk, maximize intestinal perfusion, and promote a healthy microbiome.

RESULTS

The primary outcome measure, NEC in VLBW infants, decreased from 0.17 cases/100 VLBW patient days to 0.029, an 83% reduction, while the compliance with a standardized feeding protocol improved.

CONCLUSION

Through reliable implementation of evidence-based practices, this project reduced the regional rate of NEC by 83%. A key outcome and primary driver of success was standardization across multiple NICUs, resulting in consistent application of best practices and reduction in variation.

Clinical Outcomes Related to the Gastrointestinal Trophic Effects of Erythropoietin in Preterm Neonates: A Systematic Review and Meta-Analysis

Erythropoietin (EPO) plays an important role in the development and maturation of the gastrointestinal tract. Recombinant EPO (rEPO) has been used to prevent anemia of prematurity. The gastrointestinal trophic effects of EPO may reduce feeding intolerance and necrotizing enterocolitis (NEC) in preterm neonates. The aim of this systematic review of randomized controlled trials (RCTs) was to evaluate the effects of rEPO on clinical outcomes such as feeding intolerance, stage II or higher NEC, any stage NEC, sepsis, retinopathy of prematurity, and bronchopulmonary dysplasia in preterm neonates. Twenty-five RCTs (intravenous: 13; subcutaneous: 10; enteral: 2; n = 4025) were eligible for inclusion. Meta-analysis of data from 17 RCTs (rEPO compared with placebo) with the use of a fixed-effects model showed no significant effect of rEPO on stage II or higher NEC (RR: 0.87; 95% CI: 0.64, 1.19; P = 0.39). Meta-analysis of data from 25 RCTs (rEPO compared with placebo) showed that rEPO significantly decreased the risk of any stage NEC [cases/total sample: 120/2058 (5.83%) compared with 146/1967 (7.42%); RR: 0.77; 95% CI: 0.61, 0.97; P = 0.03]. Only one RCT reported on time to full feedings. Meta-analysis of data from 15 RCTs showed a significant reduction in late-onset sepsis after rEPO administration (RR: 0.81; 95% CI: 0.71, 0.94; P = 0.004). Meta-analysis of 13 RCTs showed no significant effect of rEPO on mortality, retinopathy of prematurity, and bronchopulmonary dysplasia. Prophylactic rEPO had no effect on stage II or higher NEC, but it reduced any stage NEC, probably by reducing feeding intolerance, which is often labeled as stage I NEC. Adequately powered RCTs are required to confirm these findings.

Expert consensus to weight an adherence score for audit and feedback of practices that prevent necrotizing enterocolitis in very low birth weight infants

OBJECTIVE

Necrotizing enterocolitis (NEC) is a catastrophic abdominal complication threatening the life of premature infants, but adoption of prevention and early recognition practices differs as do NEC rates in Neonatal Intensive Care Units (NICUs). The purpose of this research was to validate and weight an evidence-based adherence score (aka NEC-Zero Adherence Score) to prevent and foster timely recognition of NEC.

STUDY DESIGN

An electronic Delphi (e-Delphi) approach was used to identify consensus. NEC experts were recruited via the NEC Society and surveyed until consensus and stability criteria for the Delphi were met (≥70% consensus and mean responses changed <15% between rounds).

RESULTS

Expert panelists (n=22) were experienced (M=17.6, SD 11years) and predominately physicians (68%) or neonatal nurse practitioners (18%). Consensus (>70% by item) supported a 10 point score. Points were distributed across 1) an exclusive human milk diet (5 points), 2) standardized feeding protocols (3 points), 3) antibiotic stewardship (1 point), and 4) a unit-specified approach to early recognition (1 point). Withholding feeding during transfusion was controversial (M=0.50, SD 0.73) and met consensus criteria to drop from the score.

CONCLUSIONS

Holding feeding during transfusion was dropped from the score. Relationships between the score and unit NEC rates as well as its utility for use in audit and feedback should be studied in the future.

Risk factors for necrotizing enterocolitis in very preterm infants: a case-control study in southwest China

OBJECTIVE

The objective of this study is to investigate perinatal risk factors for necrotizing enterocolitis (NEC) in very preterm infants.

METHODS

This retrospective study included all preterm infants with a gestational age <32 weeks attending our institution from 2013 to 2016. The NEC group comprised patients with NEC enrolled according to the inclusion criteria. Controls were selected from the database and were matched for gender, gestational age, and birth weight. Enumeration data are expressed as percentages (%) and were compared using the χ² test. Quantitative data are expressed as the mean (standard deviation) and were compared using Student's t-test. Conditional logistic regression analyses were performed to identify the factors significantly associated with NEC.

RESULTS

During the study period, 945 very preterm infants were admitted to the neonatal intensive care unit, of whom 46 (4.87%) acquired NEC. A total of 33 cases were enrolled in the NEC group, and 33 controls were selected from the database. Univariate analyses revealed significant differences between groups in the incidence of maternal placenta previa, neonatal infection symptoms, septicemia, and intravenous aminophylline administration (p < .05). Conditional logistic regression analysis demonstrated statistically significant associations of neonatal septicemia (odds ratio [OR] = 4.000, p = .043) and intravenous aminophylline (OR = 4.922, p = .035) with NEC.

CONCLUSION

Neonatal septicemia and intravenous aminophylline use are risk factors associated with NEC development in very preterm infants.

Standardized feeding regimen for reducing necrotizing enterocolitis in preterm infants: an updated systematic review

OBJECTIVE

A systematic review (2005) of observational studies has reported 87% reduction in the incidence of necrotizing enterocolitis (NEC) after introducing standardized feeding regimen (SFR) in preterm infants. Considering the many new studies in this field since 2005 and the continued health burden of NEC, we aimed to systematically review the incidence of NEC in preterm infants 'before' vs 'after' implementing a SFR.

STUDY DESIGN

PubMed, EMBASE, CINAHL and E-abstracts from the Pediatric Academic Society meetings and other pediatric and neonatal conference proceedings were searched in May 2016. Observational studies reporting incidence of NEC before and after implementing a SFR were included. Relevant data were extracted independently by two reviewers. Meta-analysis was conducted using random effects model (REM) and results rechecked with fixed effects model.

RESULTS

Pooled results from 15 observational studies (N=18 160) using REM showed that SFR significantly reduced the incidence of NEC (risk ratio 0.22; 95% confidence interval 0.13 to 0.36; P<0.00001; I2=74%). The results remained significant after comparing studies in two epochs (1978 to 2003 vs 2004 to 2016).

CONCLUSION

SFR continues to be an important tool in prevention of NEC in preterm infants.

Red blood cell transfusion in premature infants leads to worse necrotizing enterocolitis outcomes

BACKGROUND

Necrotizing enterocolitis (NEC) is a severe intestinal disease of premature infants with high mortality. Studies suggest a causative relationship between red blood cell (RBC) transfusion and NEC; however, whether RBC transfusion leads to worse outcomes in NEC is unknown. We sought to determine whether RBC transfusion was associated with an increased risk of surgical NEC and mortality.

METHODS

In this retrospective study, 115 patients were enrolled with NEC Bell's stage 2A or greater from 2010-2015. Patients were classified based on the timing of RBC transfusion before NEC: ≤72 h, >72 h, and no transfusion. Variables including gestational age (GA), birth weight (BW), feedings, and hematocrit levels were analyzed. Outcomes were surgical intervention for NEC following RBC transfusion and mortality.

RESULTS

Twenty-three (20%) infants developed NEC ≤ 72 h after RBC transfusion, 16 (69.6%) required surgery with a mortality rate of 21.7% (n = 5). Seventeen (15%) infants developed NEC > 72 h after RBC transfusion, 12 (70.6%) required surgery with a mortality rate of 23.5% (n = 4). 75 (65%) patients developed NEC without RBC transfusion, 17 (22.7%) required surgery with a mortality rate of 4% (n = 3). Lower GA and BW were significantly associated with RBC transfusion and the need for surgical intervention. RBC transfusion ≤72 h before NEC was associated with surgical NEC (pairwise adjusted P < 0.001) and mortality (pairwise adjusted P = 0.048). However, multivariable logistic regression analysis revealed RBC transfusion is not an independent risk factor for surgical NEC.

CONCLUSIONS

Infants of lower GA and BW were more likely to receive an RBC transfusion before NEC, which was significantly associated with surgical intervention and an increasing risk of mortality. Judicious use of transfusions in premature infants may improve NEC outcomes.

A critical question for NEC researchers: Can we create a consensus definition of NEC that facilitates research progress?

In the last decades the reported incidence of preterm necrotizing enterocolitis (NEC) has been declining in large part due to implementing comprehensive NEC prevention initiatives, including breast milk feeding, standardized feeding protocols, transfusion guidelines, and antibiotic stewardship and improving the rigor with which non-NEC cases are excluded from NEC data. However, after more than 60 years of NEC research in animal models, the promise of a "magic bullet" to prevent NEC has yet to materialize. There are also serious issues involving clinical NEC research. There is a lack of a common, comprehensive definition of NEC. National datasets have their own unique definition and staging definitions. Even within academia, randomized trials and single center studies have widely disparate definitions. This makes NEC metadata of very limited value. The world of neonatology needs a comprehensive, universal, consensus definition of NEC. It also needs a de-identified, international data warehouse.

Comparison of enteral feeding of preterm infants between two hospitals in China and United States

AIM

To compare the details of preterm infants enteral feeding between the two hospitals in China and in the United States, and to analyze the reason of the differences.

METHODS

A retrospective cohort study was conducted. Infants < 32 weeks were enrolled from Cincinnati University Hospital (CUH) during January 2011 to January 2012 and Peking Union Medical College Hospital (PUMCH) during January 2011 to May 2012. Basic data and enteral feeding data of the two groups were compared.

RESULTS

Eighty-two infants in CUH group and 74 infants in PUMCH group were enrolled, infants in CUH group were much smaller than PUMCH group (gestational age (29.1 ± 2.0) versus (30.6 ± 1.3) weeks, p = 0.000, birth weight (1204 ± 328) versus (1406 ± 320) g, p = 0.000). Significantly more infants in CUH group received human milk as the first enteral feeding (78/82 versus 7/74, p = 0.000). Human milk feeding rate in first 28 days in CUH group was much higher (77/82 versus 7/74, p = 0.000). The initial milk volume, and the milk volume on the 7th, 14th, 21st and 27th day of CUH group were significant larger [(15.9 versus 9.3 ml/kg·d, p = 0.000), (79.8 versus 35.2 ml/kg·d, p = 0.000), (133.2 versus 76.4 ml/kg·d, p = 0.000), (140.6 versus 108.6 ml/kg·d, p = 0.000), (142.2 versus 121.5 ml/kg·d, p = 0.002)]. CUH group achieved full enteral feeding sooner (12.0 versus 22.4 d, p = 0.000).

CONCLUSION

Preterm infants achieved full enteral feeding sooner at CUH compared to PUMCH. Human milk feeding may improve enteral feeding tolerance. We need more aggressive enteral feeding proposal in PUMCH.

Etiology and medical management of NEC

Necrotising enterocolitis (NEC) is a serious infection of the bowel that predominantly affects preterm infants and is a leading cause for mortality and morbidity in preterm infants. It involves a spectrum of pathology including widespread inflammation of the intestinal mucosa, invasion of the immature gut by enteric gas forming bacteria, dissection of the gut wall and portal veins by this gas, often culminating in ischemic necrosis of the intestine. This article provides an overview of the incidence, etio-pathological risk factors, preventive strategies and medical management of NEC.

The complete blood cell count in a refined cohort of preterm NEC: the importance of gestational age and day of diagnosis when using the CBC to estimate mortality

OBJECTIVE

The value of the white blood cell count (WBC) in necrotizing enterocolitis (NEC) is controversial. One reason for this confusion may be that the various WBC lineages change substantially with increasing gestational age and thereby age of NEC onset. This study postulated that if a data set was large enough and the diagnosis of NEC clean enough, absolute WBC counts would facilitate prediction of NEC mortality. The objective of this study was to determine whether absolute WBC counts enhance the prediction of NEC mortality.

STUDY DESIGN

A de-identified data subset from the Pediatrix national data set specific to the diagnoses of NEC in patients who had a CBC drawn on the day of diagnosis (exclusive of the diagnoses of spontaneous intestinal perforations and congenital anomalies) was the target for analysis. Values of primary interest included: gestation, day of diagnosis, absolute WBC count, platelet count, hematocrit, mortality and the day of diagnosis. Stepwise regression analysis was used to predict mortality.

RESULT

A total of 4059 (79%) survivors and 1107 (21%) infants who died with a diagnosis of medical or surgical NEC were included in the data set. Associations with mortality were found with low gestational age, low platelet count, low hematocrit, high band/segmented neutrophil ratio, earlier day of diagnosis, high birth weight z-score, non-white race, no antenatal steroids in gestations above 24 weeks, absolute lymphocyte count adjusted for gestational age, and absolute monocyte count high and low values. A stepwise regression analysis yielded a receiver-operator curve of 0.819 with a sensitivity of 65% and specificity of 84%.

CONCLUSION

Absolute WBC values enhance prediction of NEC survival when used in combination with readily available data on the day of NEC diagnosis.

Cluster of late preterm and term neonates with necrotizing enterocolitis symptomatology: descriptive and case-control study

OBJECTIVE

To investigate a necrotizing enterocolitis (NEC) cluster of late preterm and term neonates (gestational age ≥34 weeks).

METHODS

We conducted a descriptive and a case-control study. Medical records of neonates with modified Bell stage ≥ IB NEC and matched controls were reviewed, in addition to microbiological and environmental investigation. Study variables included maternal/delivery and neonatal factors, medications, procedures and feeding practices. Univariable/multivariable logistic regression analyses were performed for all and for stage ≥ II cases.

RESULTS

Out of 1841 late preterm and term neonates, 10 stage IB and 10 stage ≥ II [mean(SD) birthweight 2529.3 (493.04) g, gestational age 36.96 (1.48) weeks] presented with NEC symptomatology at mean 4.6 (range 2-8) days. Nearly all (19/20) resulted from high-risk pregnancies and received postpartum intermediate care. All were exclusively or partly formula fed. Most (14/20) were born by cesarean delivery. Eight underwent surgery, with no fatality. Intermediate care (p = 0.006), transient tachypnea (p = 0.049), not receiving breast milk (p = 0.019) and in addition intrauterine growth restriction (IUGR) (p = 0.017) for stage ≥ II cases were independently associated with NEC.

CONCLUSIONS

Late preterm and term neonates in need of intermediate care, with IUGR and transient tachypnea were susceptible to NEC; feeding with breast milk was an important protective factor.

Early gradual feeding with bovine colostrum improves gut function and NEC resistance relative to infant formula in preterm pigs

It is unclear when and how to start enteral feeding for preterm infants when mother's milk is not available. We hypothesized that early and slow advancement with either formula or bovine colostrum stimulates gut maturation and prevents necrotizing enterocolitis (NEC) in preterm pigs, used as models for preterm infants. Pigs were given either total parenteral nutrition (TPN, n = 14) or slowly advancing volumes (16-64 ml·kg(-1)·day(-1)) of preterm infant formula (IF, n = 15) or bovine colostrum (BC, n = 13), both given as adjunct to parenteral nutrition. On day 5, both enteral diets increased intestinal mass (27 ± 1 vs. 22 ± 1 g/kg) and glucagon-like peptide 2 release, relative to TPN (P < 0.05). The incidence of mild NEC lesions was higher in IF than BC and TPN pigs (60 vs. 0 and 15%, respectively, P < 0.05). Only the IF pigs showed reduced gastric emptying and gastric inhibitory polypeptide release, and increased tissue proinflammatory cytokine levels (IL-1β and IL-8, P < 0.05) and expression of immune-related genes (AOAH, LBP, CXCL10, TLR2), relative to TPN. The IF pigs also showed reduced intestinal villus-to-crypt ratio, lactose digestion, and some plasma amino acids (Arg, Cit, Gln, Tyr, Val), and higher intestinal permeability, compared with BC pigs (all P < 0.05). Colonic microbiota analyses showed limited differences among groups. Early feeding with formula induces intestinal dysfunction whereas bovine colostrum supports gut maturation when mother's milk is absent during the first week after preterm birth. A diet-dependent feeding guideline may be required for newborn preterm infants.

Reducing necrotizing enterocolitis in very low birth weight infants using quality-improvement methods

OBJECTIVE

Owing to a rise in necrotizing enterocolitis (NEC, stage ⩾ 2) among very low birth weight (VLBW, birth weight <1500 g) infants from 4% in 2005 to 2006 to 10% in 2007 to 2008, we developed and implemented quality improvement (QI) initiatives. The objective was to evaluate the impact of QI initiatives on NEC incidence in VLBW infants.

STUDY DESIGN

In September 2009, we developed an NEC QI multidisciplinary team that conducted literature reviews and reviewed practices from other institutions to develop a feeding protocol, which was implemented in December 2009. The team tracked intervention compliance and occurrence of NEC stage ⩾ 2. In May 2010, we reviewed our nasogastric tube practice and relevant literature to develop a second intervention that reduced nasogastric tube indwelling time. The infants were divided into three groups: baseline (January 2008 to Novovember 2009, n219), QI phase 1 (December 2009 to May 2010, n62) and QI phase 2 (June 2010 to November 2011, n170).

RESULT

The NEC incidence did not decrease after implementation of the feeding protocol in QI phase 1 (19.4%) but did decline significantly after changing nasogastric tube management in QI phase 2 (2.9%). Multivariable logistic regression analysis demonstrated a significant relationship between QI phase and the incidence of NEC.

CONCLUSION

QI initiatives were effective in decreasing NEC incidence in our high human milk-feeding NICU. Nasogastric tube bacterial contamination may have contributed to our peak in NEC incidence.

Risk factors for necrotising enterocolitis in an HIV-endemic region

BACKGROUND

Several risk factors have been implicated in the development of necrotising enterocolitis (NEC). However, little has been reported on the risk factors for NEC in infants born in a setting where exposure to maternal human immunodeficiency virus (HIV) is prevalent.

OBJECTIVES

To determine maternal and infant characteristics associated with NEC in a setting with a high prevalence of HIV infection and to compare clinical presentation and mortality of NEC in HIV-exposed and unexposed infants.

METHODS

This was a retrospective, case-control study. Infants with a confirmed diagnosis of NEC, admitted between January 2005 and December 2008 were identified as cases. Two controls for each case were selected by matching them for birthweight, gestational age and date of birth. Hospital records were reviewed for maternal and infant characteristics.

RESULTS

One hundred and ten infants with confirmed NEC were identified and 220 were selected as controls. Median birthweight and gestational age were similar between cases and controls, (1370 and 1380 g, P = 0·96, and 31 weeks each, P = 0·62, respectively). Lack of use of antenatal corticosteroids (ANS) (OR 2·77, 95% CI 1·42-5·38, P = 0·003), presence of chorio-amnionitis (OR 7·28, 95% CI 2·16-24·51, P = 0·001) and not mechanically ventilated at birth (OR 3·54, 95% CI 1·29-9·69, P = 0·01) were independently associated with NEC. Maternal HIV status was not associated with NEC. Clinical presentation and mortality from NEC were similar between HIV-exposed and unexposed infants.

CONCLUSIONS

Infants who develop NEC were less likely to have received mechanical ventilation at birth, suggesting that they were less critically ill when born. Use of ANS should be encouraged as it is protective against NEC. Infants born to HIV-infected mothers were not at increased risk of NEC.

Intestinal alkaline phosphatase is protective to the preterm rat pup intestine

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common surgical emergency in neonates, with a mortality rate between 10 and 50%. The onset of necrotizing enterocolitis is highly variable and associated with numerous risk factors. Prior research has shown that enteral supplementation with intestinal alkaline phosphatase (IAP) decreases the severity of NEC. The aim of this study is to investigate whether IAP is protective to the preterm intestine in the presence of formula feeding and in the absence of NEC.

METHODS

Preterm rat pups were fed formula with or without supplementation with IAP, and intestine was obtained on day of life 3 for analysis of IAP activity, mRNA expression of TNFα, IL-6 and iNOS and permeability and cytokine expression after LPS exposure.

RESULTS

There was no difference in the absolute and intestine specific alkaline phosphatase activity in both groups. Rat pups fed IAP had decreased mRNA expression of the inflammatory cytokines TNFα, IL-6 and iNOS. Pups supplemented with IAP had decreased permeability and inflammatory cytokine expression after exposure to LPS ex vivo when compared to formula fed controls.

CONCLUSIONS

Our results support that IAP is beneficial to preterm intestine and decreases intestinal injury and inflammation caused by LPS.

Prevention and early recognition of necrotizing enterocolitis: a tale of 2 tools--eNEC and GutCheckNEC

BACKGROUND AND SIGNIFICANCE

Risk for neonatal necrotizing enterocolitis (NEC) is complex, reflecting its multifactorial pathogenesis.

PURPOSE

To improve risk awareness and facilitate communication among neonatal caregivers, especially nurses, 2 tools were developed.

DESIGN

GutCheck was derived and validated as part of a formal research study over 3 phases, evidence synthesis, expert consensus building, and statistical modeling. The Wetzel/Krisman tool, eNEC, was developed and tested as part of a quality improvement initiative in a single clinical setting using evidence synthesis, review by internal expert clinicians, and implementation and evaluation of its use by direct line neonatal staff. Refinement of both tools is under way to evaluate their effect on clinical decision making, early identification of NEC and surgical NEC.

METHODS AND MAIN OUTCOMES

Clinicians can take an active role to reduce NEC in their units by focusing on modifiable risk factors such as adoption of standardized feeding protocols, preferential feeding of human milk, and antibiotic and histamine blocker stewardship.

RESULTS

Feeding during transfusion remains controversial, but judicious use of transfusions, adoption of transfusion guidelines, and withholding feeding during transfusion are feasible measures with potential benefit to prevent NEC and confer little risk.

Discrimination of GutCheck(NEC): a clinical risk index for necrotizing enterocolitis

OBJECTIVE

Better measures are needed to identify infants at risk for developing necrotizing enterocolitis (NEC) and facilitate communication about risk across transitions. Although NEC is multi-factorial, quantification of composite risk for NEC in an individual infant is not clearly defined. The objective of this study was to describe the derivation, validation and calibration testing of a novel clinical NEC risk index, GutCheck(NEC). Individual risk factors were weighted to assess composite odds of developing NEC. GutCheck(NEC) is designed to improve communication about NEC risk and coordination of care among clinicians across an infant's clinical course.

STUDY DESIGN

On the basis of a synthesis of research evidence about NEC risk and an e-Delphi study including 35 neonatal experts, we identified NEC risk factors believed by the experts to be most relevant for a NEC risk index, then applied a logistic model building process to derive and validate GutCheck(NEC). De-identified data from the Pediatrix BabySteps Clinical Data Warehouse (discharge date 2007 to 2011) were split into three samples for derivation, validation and calibration. By comparing infants with medical NEC, surgical NEC and those who died to infants without NEC, we derived the logistic model using the un-matched derivation set. Discrimination was then tested in a case-control matched validation set and an un-matched calibration set using receiver operating characteristic curves.

RESULT

Sampled from a cohort of 58 820 infants, the randomly selected derivation set (n=35 013) revealed nine independent risk factors (gestational age, history of packed red blood cell transfusion, unit NEC rate, late-onset sepsis, multiple infections, hypotension treated with inotropic medications, Black or Hispanic race, outborn status and metabolic acidosis) and two risk reducers (human milk feeding on both days 7 and 14 of life, and probiotics). Unit NEC rate carried the most weight in the summed score. Validation using a 2:1 matched case-control sample (n=360) demonstrated fair to good discrimination. In the calibration set (n=23 447), GutCheck(NEC) scores (range 0 to 58) discriminated those infants who developed surgical NEC (area under the curve (AUC)=0.84, 95% confidence interval (CI) 0.82 to 0.84) and NEC leading to death (AUC=0.83, 95% CI 0.81 to 0.85), more accurately than medical NEC (AUC= 0.72, 95% CI 0.70 to 0.74).

CONCLUSION

GutCheck(NEC) represents weighted composite risk for NEC and discriminated infants who developed NEC from those who did not with very good accuracy. We speculate that targeting modifiable NEC risk factors could reduce national NEC prevalence.

Conditioned medium from Bifidobacteria infantis protects against Cronobacter sakazakii-induced intestinal inflammation in newborn mice

Necrotizing enterocolitis (NEC) is associated with a high morbidity and mortality in very low birth weight infants. Several hypotheses regarding the pathogenesis of NEC have been proposed but to date no effective treatment is available. Previous studies suggest that probiotic supplementation is protective. We recently reported that probiotic (Bifidobacterium infantis) conditioned medium (PCM) has an anti-inflammatory effect in cultured fetal human intestinal cells (H4) and fetal intestine explants. In this study, we tested in vivo whether PCM protects neonatal mice from developing intestinal inflammation induced by exposure to Cronobacter sakazakii (C. sakazakii), an opportunistic pathogen associated with NEC. We found that infected neonatal mice had a significantly lower body weight than control groups. Infection led to ileal tissue damage including villous rupture, disruption of epithelial cell alignment, intestinal inflammation, apoptotic cell loss, and decreased mucus production. Pretreatment with PCM prevented infection caused decrease in body weight, attenuated enterocyte apoptotic cell death, mitigated reduced mucin production, and maintained ileal structure. Infected ileum expressed reduced levels of IκBα, which could be restored upon pretreatment with PCM. We also observed a nuclear translocation of NF-κB p65 in H4 cells exposed to C. sakazakii, which was prevented in PCM-pretreated cells. Finally, treatment of neonatal mice with PCM prior to infection sustained the capacity of ileal epithelial proliferation. This study suggests that an active component(s) released into the culture medium by B. infantis may prevent ileal damage by a pathogen linked to NEC.

Heparin-binding EGF-like growth factor (HB-EGF) therapy for intestinal injury: Application and future prospects

Throughout the past 20 years, we have been investigating the potential therapeutic roles of heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor family, in various models of intestinal injury including necrotizing enterocolitis (NEC), intestinal ischemia/reperfusion (I/R) injury, and hemorrhagic shock and resuscitation (HS/R). Our studies have demonstrated that HB-EGF acts as an effective mitogen, a restitution-inducing reagent, a cellular trophic factor, an anti-apoptotic protein and a vasodilator, via its effects on various cell types in the intestine. In the current paper, we have reviewed the application and therapeutic effects of HB-EGF in three classic animal models of intestinal injury, with particular emphasis on its protection of the intestines from NEC. Additionally, we have summarized the protective functions of HB-EGF on various target cells in the intestine. Lastly, we have provided a brief discussion focusing on the future development of HB-EGF clinical applications for the treatment of various forms of intestinal injury including NEC.

Recent advances toward defining the benefits and risks of erythrocyte transfusions in neonates

Like many treatments available to small or ill neonates, erythrocyte transfusions carry both benefits and risks. This review examines recent publications aimed at better defining those benefits and those risks, as means of advancing evidence-based neonatal intensive care unit transfusion practices. Since decisions regarding whether to not to order an erythrocyte transfusion are based, in part, on the neonate's blood haemoglobin concentration, the authors also review recent studies aimed at preventing the haemoglobin from falling to a point where a transfusion is considered.

The cost of using donor human milk in the NICU to achieve exclusively human milk feeding through 32 weeks postmenstrual age

OBJECTIVES

Donor human milk (DHM) is increasingly being used in neonatal intensive care units (NICUs) to achieve exclusive human milk (EHM) feedings in preterm infants. The aim of the study was to determine the cost of DHM to achieve EHM feeding for very preterm infants. The hypothesis was that the cost of DHM per infant is modulated by the availability of mother's own milk (MOM).

SUBJECTS AND METHODS

Preterm infants (<1,500 g at birth weight or <33 weeks in gestational age) were retrospectively evaluated for a 1-year interval. MOM, DHM, and formula feeding categories were determined. A DHM feeding log was retrospectively analyzed for feeding volumes (in milliliters) and duration (in days). Four categories were created, based on maternal ability to provide sufficient breastmilk volumes and her intention to breastfeed. The volume, duration, and cost of DHM were calculated for each category.

RESULTS

Forty-six of the 64 (72%) infants admitted to the NICU who were <33 weeks in gestational age received DHM. Four categories of DHM use were observed. The mean costs of DHM were $27 for infants of mothers who provided sufficient breastmilk through to discharge, $154 for infants of mothers who had insufficient milk supply during admission, $281 for infants of mothers who went home on formula but received any volume of MOM during admission, and $590 for infants who received no MOM during admission.

CONCLUSIONS

Most NICU mothers (72%) of very preterm infants were unable to provide all of the milk necessary for an EHM diet. Few infants (15%) received exclusively DHM. The cost of DHM per NICU infant ranged from $27 to $590 and was influenced by the mother's willingness or ability to provide human milk.

Neonates presenting with bloody stools and eosinophilia can progress to two different types of necrotizing enterocolitis

OBJECTIVE

We hypothesized that neonates with bloody stools and concomitant eosinophilia are likely to have atopic enteropathy rather than necrotizing enterocolitis (NEC).

STUDY DESIGN

This was a retrospective cross-sectional study using electronic medical records and paper charts. Records of neonates admitted to any Intermountain Healthcare NICU between 1 January 2005 and 30 June 2010 were eligible if 'bloody stools' were listed in any archive. Qualifying records were divided into two groups depending on whether or not within 72 h of passing bloody stool eosinophil counts were above the 95th percentile reference range limit for age.

RESULT

Bloody stools were identified in 275 predominantly Caucasian neonates. Fifty-four of these had eosinophilia and 221 had normal eosinophil counts. Those with eosinophilia were born at a slightly younger gestational age (31.3 ± 4.6 vs 32.6 ± 4.0 weeks, mean ± s.d., P=0.032). Contrary to our hypothesis, those with eosinophilia did not have a lower rate of pneumatosis or bowel resection, or death ascribed to NEC. Eosinophilia was more common among those who had a red blood cell (RBC) transfusion within 48 h before passing bloody stools (P<0.001). Those with a recent RBC transfusion were the only neonates to have NEC surgery or to die from NEC. Preceding the bloody stools, those with no antecedent transfusion had been fed a larger volume (P=0.014), and had trends toward receiving calorically enriched feedings (P=0.055) and recent addition of human milk fortifier (P=0.060). Eosinophil counts following RBC transfusion tended to increase for 3-6 days, but when bloody stools were not preceded by transfusion the eosinophil counts were more static over that period.

CONCLUSION

In this predominantly Caucasian group of neonates with bloody stools, the presence of eosinophilia did not identify a benign condition distinct from NEC. A total of 44% of these neonates had transfusion-associated NEC. Eosinophils could have a previously unrecognized role in the pathogenesis of this NEC subtype.

Hospital and neurodevelopmental outcomes of extremely low-birth-weight infants with necrotizing enterocolitis and spontaneous intestinal perforation

OBJECTIVE

We sought to determine the incidence of necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) in surviving extremely low-birth-weight (ELBW, <1000 g birth weight) infants and to establish the impact of NEC on outcomes by hospital discharge and at 18 to 22 months adjusted age in a large, contemporary, population-based practice.

STUDY DESIGN

Hospital outcome data for all ELBW infants born in the greater Cincinnati region from 1998 to 2009 were extracted from the National Institute of Child Health Neonatal Research Network Database. Neurodevelopmental outcome at 18 to 22 months was assessed using Bayley Scales of Infant Development-II scores for Mental Developmental Index and Psychomotor Developmental Index. Multivariable logistic regression was used and adjusted odds ratios reported to control for confounders.

RESULT

From 1998 to 2009, ELBW infants accounted for 0.5% of the 352 176 live-born infants in greater Cincinnati. The incidence of NEC was 12%, with a 50% case-fatality rate. Death before discharge, morbid complications of prematurity and neurodevelopmental impairment were all increased among infants diagnosed with NEC. Infants with surgical NEC and SIP had a higher incidence of death, but long-term neurodevelopmental outcomes were not different comparing surviving ELBW infants with medical NEC, surgical NEC and SIP.

CONCLUSION

Although ELBW infants comprise a very small proportion of live-born infants, those who develop NEC and SIP are at an increased risk for death, morbid complications of prematurity and neurodevelopmental impairment. No significant differences in neurodevelopmental outcomes were observed between the medical and surgical NEC and SIP groups.

Intestinal alkaline phosphatase administration in newborns decreases systemic inflammatory cytokine expression in a neonatal necrotizing enterocolitis rat model

BACKGROUND

Supplementation of intestinal alkaline phosphatase (IAP), an endogenous protein expressed in the intestines, decreases the severity of necrotizing enterocolitis (NEC)-associated intestinal injury and permeability. We hypothesized that IAP administration is protective in a dose-dependent manner of the inflammatory response in a neonatal rat model.

MATERIALS AND METHODS

Pre- and full-term newborn Sprague-Dawley rat pups were sacrificed on day of life 3. Control pups were vaginally delivered and dam fed. Preterm pups were delivered via cesarean section and exposed to intermittent hypoxia and formula feeds containing lipopolysaccharide (NEC) with and without IAP. Three different standardized doses were administered to a group of pups treated with 40, 4, and 0.4U/kg of bovine IAP (NEC+IAP40, IAP4, or IAP0.4U). Reverse transcription-real-time polymerase chain reaction (RT-PCR) for inducible nitric oxide synthase (iNOS) and tumor necrosis factor (TNF)-α on liver and lung tissues and serum cytokine analysis for interleukin (IL)-1β, IL-6, IL-10, and TNF-α were performed. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests, expressed as mean±standard error of the mean and P≤0.05 considered significant.

RESULTS

Levels of cytokines IL-1β, IL-6, and TNF-α increased significantly in NEC versus control, returning to control levels with increasing doses of supplemental enteral IAP. Hepatic and pulmonary TNF-α and iNOS messenger ribonucleic acid expressions increased in NEC, and the remaining elevated despite IAP supplementation.

CONCLUSIONS

Proinflammatory cytokine expression is increased systemically with intestinal NEC injury. Administration of IAP significantly reduces systemic proinflammatory cytokine expression in a dose-dependent manner. Early supplemental enteral IAP may reduce NEC-related injury and be useful for reducing effects caused by a proinflammatory cascade.

Intestinal alkaline phosphatase administration in newborns is protective of gut barrier function in a neonatal necrotizing enterocolitis rat model

BACKGROUND

Previously, we have shown that supplementation of intestinal alkaline phosphatase (IAP) decreased severity of necrotizing enterocolitis (NEC)-associated intestinal injury. We hypothesized that IAP administration is protective of intestinal epithelial barrier function in a dose-dependent manner.

METHODS

Control rat pups were vaginally delivered and breast-fed. Premature rats were divided into 4 groups: formula fed with lipopolysaccharide and hypoxia (NEC) or additional daily bovine IAP 40, 4, or 0.4 U/kg (NEC + IAP 40 U, IAP 4 U, or IAP 0.4 U).

RESULTS

Necrotizing enterocolitis is associated with decreased IAP protein expression and activity. Supplemental IAP increases IAP activity in intestinal homogenates and decreased NEC injury score in a dose-dependent manner. Intestinal injury as measured by fluorescein isothiocyanate-dextran flux from ileal loops showed increased permeability vs control, but supplemental IAP reversed this. Tight junction proteins claudin-1, claudin-3, occludin, and zonula occludin 1 were elevated in the NEC and IAP-treated groups with differences in expression patterns. No differences in messenger RNA levels were observed on postinjury day 3. Intestinal alkaline phosphatase administration decreases intestinal NEC injury in a dose-dependent manner.

CONCLUSION

Early enteral supplemental IAP may reduce NEC-related injury and may be useful for preserving the intestinal epithelial barrier function.

Necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the most common acquired gastrointestinal disease of premature neonates and is a serious cause of morbidity and mortality. NEC is one of the leading causes of death in neonatal intensive care units. Surgical treatment is necessary in patients whose disease progresses despite medical therapy. Surgical options include peritoneal drainage and laparotomy, with studies showing no difference in outcome related to approach. Survivors, particularly those requiring surgery, face serious sequelae.

Necrotizing enterocolitis risk: state of the science

Necrotizing enterocolitis (NEC) is the most common cause of gastrointestinal-related morbidity and mortality in the neonatal intensive care unit (NICU). Its onset is sudden and the smallest, most premature infants are the most vulnerable. Necrotizing enterocolitis is a costly disease, accounting for nearly 20% of NICU costs annually. Necrotizing enterocolitis survivors requiring surgery often stay in the NICU more than 90 days and are among those most likely to stay more than 6 months. Significant variations exist in the incidence across regions and units. Although the only consistent independent predictors for NEC remain prematurity and formula feeding, others exist that could increase risk when combined. Awareness of NEC risk factors and adopting practices to reduce NEC risk, including human milk feeding, the use of feeding guidelines, and probiotics, have been shown to reduce the incidence of NEC. The purpose of this review is to examine the state of the science on NEC risk factors and make recommendations for practice and research.

Fulminant necrotizing enterocolitis in a multihospital healthcare system

OBJECTIVE

A subset of necrotizing enterocolitis (NEC) cases is fulminant, characterized by rapid progression to death with massive bowel necrosis found at laparotomy or autopsy. We sought to identify and report all such cases in a multihospital healthcare system during the past 9 years and to characterize this entity using case-control methodologies.

STUDY DESIGN

This was a multicentered, cross-sectional, historic cohort study conducted using Intermountain Healthcare hospital patient data. All neonates who died of NEC within 48 h of onset, during 2001 to 2009, were compared with two matched control groups: (1) demographically matched controls who developed non-fulminant NEC, (2) demographically matched controls that did not develop NEC.

RESULT

During this period, 2 71 327 live births occurred in the Intermountain Healthcare hospitals. Of these, 318 had a diagnosis of NEC (Bell stage ≥II). Also during this period, 205 other neonates were transferred into an Intermountain hospital for treatment of NEC. Of these 523 NEC cases, 35 (6.7%) had a fulminant course. Compared with the non-fulminant cases, the fulminant group were born at lower weight (1088±545 vs 1652±817 g, P=0.000) and earlier gestational age (27.5±3.3 vs 31.1±4.4 weeks, P=0.000), and were more likely to have: (1) radiographic evidence of portal venous air (P=0.000), (2) hematocrit <22% (P=0.000), (3) increase in feeding volume >20 ml/kg/day (P=0.003), (4) immature to total (I/T) neutrophil ratio >0.5 (P=0.005), (5) blood lymphocyte count <4000/μl (P=0.018), (6) an increase in concentration of human milk fortifier within 48 h before developing NEC (P=0.020).

CONCLUSION

Portal venous air, anemia, rapid feeding escalation, a high I/T neutrophil ratio, a low lymphocyte count and recent increases in fortifier may all be associated with fulminant NEC.

Characteristics of patients who die of necrotizing enterocolitis

OBJECTIVE

Necrotizing enterocolitis (NEC) is associated with high morbidity and mortality among infants admitted for intensive care. The factors associated with mortality and catastrophic presentation remain poorly understood. Our objective was to describe the factors associated with mortality in infants with NEC and to quantify the degree to which catastrophic presentation contributes to mortality in infants with NEC. Catastrophic NEC was defined before data analysis as NEC that led to death within 7 days of diagnosis.

STUDY DESIGN

We performed a retrospective review of the Pediatrix's Clinical Data Warehouse (1997 to 2009, n=560,227) to compare the demographic, therapeutic and outcome characteristics of infants who survived NEC vs those who died. Associations were tested by bivariate and multivariate analysis.

RESULT

We compared the 5594 infants diagnosed with NEC and who were discharged home with 1505 infants diagnosed with NEC who died. In multivariate analysis, the factors associated with death (P<0.01 in analysis) were lower estimated gestational age, lower birth weight, treatment with assisted ventilation on the day of diagnosis of NEC, treatment with vasopressors at the time of diagnosis, and Black race. Patients who received only ampicillin and gentamicin on the day of diagnosis were less likely to die. Two-thirds of NEC deaths occurred quickly (<7 days from diagnosis), with a median time of death of one day from time of diagnosis. Infants who died within 7 days of diagnosis had a higher birth weight, more often were on vasopressors and high frequency ventilation at the time of diagnosis compared with patients who died at 7 or more days. Although mortality decreased with increasing gestational age, the proportion of deaths that occurred within 7 days was relatively consistent (65 to 75% of the patients who died) across all gestational ages.

CONCLUSION

Mortality among infants who have NEC remains high and infants who die of NEC commonly (66%) die quickly. Most of the factors associated with mortality are related to immaturity, low birth weight and severity of illness.

Evidence-based guidelines for use of probiotics in preterm neonates

BACKGROUND

Current evidence indicates that probiotic supplementation significantly reduces all-cause mortality and definite necrotising enterocolitis without significant adverse effects in preterm neonates. As the debate about the pros and cons of routine probiotic supplementation continues, many institutions are satisfied with the current evidence and wish to use probiotics routinely. Because of the lack of detail on many practical aspects of probiotic supplementation, clinician-friendly guidelines are urgently needed to optimise use of probiotics in preterm neonates.

AIM

To develop evidence-based guidelines for probiotic supplementation in preterm neonates.

METHODS

To develop core guidelines on use of probiotics, including strain selection, dose and duration of supplementation, we primarily used the data from our recent updated systematic review of randomised controlled trials. For equally important issues including strain identification, monitoring for adverse effects, product format, storage and transport, and regulatory hurdles, a comprehensive literature search, covering the period 1966-2010 without restriction on the study design, was conducted, using the databases PubMed and EMBASE, and the proceedings of scientific conferences; these data were used in our updated systematic review.

RESULTS

In this review, we present guidelines, including level of evidence, for the practical aspects (for example, strain selection, dose, duration, clinical and laboratory surveillance) of probiotic supplementation, and for dealing with non-clinical but important issues (for example, regulatory requirements, product format). Evidence was inadequate in some areas, and these should be a target for further research.

CONCLUSION

We hope that these evidence-based guidelines will help to optimise the use of probiotics in preterm neonates. Continued research is essential to provide answers to the current gaps in knowledge about probiotics.

Poly(ADP-ribose) polymerase-1: a novel therapeutic target in necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the most common gastrointestinal disease of infancy, afflicting 11% of infants born 22-28 wk GA. Both inflammation and oxidation may be involved in NEC pathogenesis through reactive nitrogen species production, protein oxidation, and DNA damage. Poly(ADP-ribose) polymerase-1 (PARP-1) is a critical enzyme activated to facilitate DNA repair using nicotinamide adenine dinucleotide (NAD+) as a substrate. However, in the presence of severe oxidative stress and DNA damage, PARP-1 overactivation may ensue, depleting cells of NAD+ and ATP, killing them by metabolic catastrophe. Here, we tested the hypothesis that NO dysregulation in intestinal epithelial cells during NEC leads to marked PARP-1 expression and that administration of a PARP-1 inhibitor (nicotinamide) attenuates intestinal injury in a newborn rat model of NEC. In this model, 56% of control pups developed NEC (any stage) versus 14% of pups receiving nicotinamide. Forty-four percent of control pups developed high-grade NEC (grades 3-4), whereas only 7% of pups receiving nicotinamide developed high-grade NEC. Nicotinamide treatment protects pups against intestinal injury incurred in the newborn rat NEC model. We speculate that PARP-1 overactivation in NEC may drive mucosal cell death in this disease and that PARP-1 may be a novel therapeutic target in NEC.

Necrotizing enterocolitis: an update

Necrotizing enterocolitis (NEC) is a leading cause of death among patients in the neonatal intensive care unit, carrying a mortality rate of 15-30%. Its pathogenesis is multifactorial and involves an overreactive response of the immune system to an insult. This leads to increased intestinal permeability, bacterial translocation, and sepsis. There are many inflammatory mediators involved in this process, but thus far none has been shown to be a suitable target for preventive or therapeutic measures. NEC usually occurs in the second week of life after the initiation of enteral feeds, and the diagnosis is made based on physical examination findings, laboratory studies, and abdominal radiographs. Neonates with NEC are followed with serial abdominal examinations and radiographs, and may require surgery or primary peritoneal drainage for perforation or necrosis. Many survivors are plagued with long term complications including short bowel syndrome, abnormal growth, and neurodevelopmental delay. Several evidence-based strategies exist that may decrease the incidence of NEC including promotion of human breast milk feeding, careful feeding advancement, and prophylactic probiotic administration in at-risk patients. Prevention is likely to have the greatest impact on decreasing mortality and morbidity related to NEC, as little progress has been made with regard to improving outcomes for neonates once the disease process is underway.