Introduction
Necrotizing enterocolitis (NEC) is an inflammatory intestinal disease that affects 5–7% of preterm neonates1. It is characterized by variable intestinal injury from epithelial injury to transmural involvement and perforation. It is also marked by inflammation and often bacterial invasion2. NEC is one of the leading causes of morbidity in preterm infants3. It affects nearly 10% of preterm infants with a birth weight of <1,500 grams4. The mortality rate for preterm infants who have extremely low birth weight (<1,000 grams) is 30–50% and for infant with a very low birth weight (VLBW) (<1,500 grams) is 10–30%, and there has not been a significant change in the past 20 years5.
To assess the severity of NEC, Bell’s classification was proposed in 1978. It categorizes the severity of NEC based on clinical and radiographic signs and remains the most widely used tool in early assessment. In recent years, however, this staging criterion has been modified as our understanding of the disease has improved, yet there continues to be controversy about the validity of this staging system at lower gestational ages (GAs)6. Severity of NEC plays a key role in both the management and the outcome of affected neonates. Neonates with proven or advanced NEC, categorized as Bell’s stage II and III, respectively, are at risk of developing peritonitis, sepsis, bowel perforation, and other severe systematic complications including capillary leak syndrome and multi-system organ failure7.
The pathophysiology of NEC is multifactorial and remains not fully understood. The risk factors for the development of the disease are multiple and some are controversial. This leads to difficulty in establishing novel strategies to prevent the development of NEC and its progression. Herein we discuss some of our latest understanding of the disease’s epidemiology, risk factors, pathophysiology, treatment strategies, and future directions.
Epidemiology
The incidence of proven NEC (Bell’s stage II and III) in preterm babies depends on both the degree of prematurity and the geographic location of the patient. A recent systematic review on the incidence of NEC in high-income countries found variation in the incidence of the disease based on GA, birth weight, and country8,9. Overall, NEC incidence was highest among the most preterm infants. In infants born at a GA of <28 weeks, the lowest reported incidence of NEC was in Japan (2%) and the highest in Australia, Canada, and Italy (7–9%)8. In neonates with a GA of between 28 and 31 weeks, reported NEC incidence was also lowest in Japan (0.2%), while other developed nations had incidence rates ranging from 2–3%. Similarly, for VLBW infants, NEC incidence ranged from 2% in Japan to 6–7% in the USA and 9% in Poland8–10. These findings collectively indicate that the degree of prematurity and low birth weight are important factors in developing NEC. The varied incidence rates between countries suggest various factors influencing the development of NEC including environment, diet, and genetic predisposition.
Risk factors
The only consistently described risk factors for NEC are formula feeding, intestinal dysbiosis, low birth weight, and prematurity11. Low birth weight and prematurity are the most commonly reported risk factors for NEC, with the lowest birth weights and GAs having the highest incidence of NEC12. Maternal factors such as chorioamnionitis, cocaine abuse, in-utero growth restriction, increased body mass index, intrahepatic cholestasis during pregnancy, lack of prenatal steroids, mode of delivery, placental abruption, preeclampsia, and smoking have inconsistently been implicated in the development of NEC13–17. In addition, many other risk factors for the development of NEC have been reported including administration of acid-suppressing medications, acute hypoxia, antibiotic exposure, blood transfusions, cardiac anomalies, neonatal anemia, and poor intestinal perfusion18–21. Finally, prolonged use of indomethacin to promote the closure of patent ductus arteriosus (PDA) has been shown to be associated with the development of NEC22,23. However, the incidence of NEC was not lower in infants who underwent primary surgical closure of PDA compared to infants treated with indomethacin24 (Table 1).
Table 1. Risk factors for the development of necrotizing enterocolitis.
Maternal factors Chorioamnionitis Cocaine abuse In-utero growth restriction Increased body mass index Intrahepatic cholestasis during pregnancy Lack of prenatal steroids Mode of delivery Placental abruption Preeclampsia Smoking |
Main risk factors Low birth weight Prematurity Formula feeding Intestinal dysbiosis |
Other risk factors Acid-suppressing medications Acute hypoxia Antibiotic exposure Blood transfusions Cardiac anomalies Neonatal anemia Poor intestinal perfusion Prolonged use of indomethacin for patent ductus arteriosus closure |
Pathophysiology
NEC affects multiple organs, and its pathophysiology appears to be multifactorial. The classical understanding of NEC pathophysiology suggests that intra-luminal bacteria disrupt and invade the intestinal epithelium at the tips of intestinal villi25. Endotoxin from these bacteria binds to Toll-like receptor 4 (TLR4) found on the intestinal epithelial cells, activating pathogen-associated molecular pattern (PAMP) receptors, which facilitate the breakdown of the gut barrier and allow bacteria to translocate26. This process subsequently leads to an intense inflammatory response in the lamina propria mediated by tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and other inflammatory cytokines27. Vasoactive substances are also released in the intestine, and those associated with NEC include platelet-activating factor (PAF), endothelin-1 (ET-1), and nitric oxide (NO)28. Intestinal inflammation also activates complement and coagulation systems. In these systems, leukocytes and platelets adhere to the endothelium, preventing blood flow in the microvascular structure of the small intestine and leading to tissue injury. Additional damage to the endothelium from adherent neutrophils and platelets also impairs NO generation needed for vasorelaxation29,30. Through the efforts of various research laboratories, including ours, potential mechanisms have been explored to investigate how the disease may develop and how it may be treated (Table 2).
Table 2. Factors involved in necrotizing enterocolitis pathophysiology.
| Nitric oxide |
| Toll-like receptor 4 |
| Microvascular blood flow (intestinal ischemia) |
| Dysbiosis |
| Reduced activity of intestinal stem cells |
Nitric oxide
The pathogenesis of NEC is likely initiated by postnatal insults on the immature intestine in the presence of some of the previously mentioned risk factors. These factors lead to the initial epithelial injury, which causes an intestinal inflammatory response and release of inflammatory mediators31. Ford et al.32 first highlighted the role of NO and that of inducible NO synthase (iNOS)-derived NO in NEC development. NO plays a critical role in NEC development, and the details of its role have been extensively explored. Once intestinal barrier failure occurs, the lamina propria is exposed to increased levels of endotoxins and other bacterial products owing to bacterial translocation33. The net result is activation of the neonatal immune system, which triggers an inflammatory cascade that leads to a severe pro-inflammatory response characterized by the release of NO, cytokines, and prostanoids. NO interacts with superoxide and leads to the production of peroxynitrite, a potent oxidant34. This subsequently leads to enterocyte apoptosis or necrosis as well as impairment of both enterocyte proliferation and epithelial repair through enterocyte migration. The imbalance between tissue injury and repair further catalyzes the inflammatory cascade involved in NEC development. The ultimate consequence of these insults is further epithelial injury with risk for bacterial translocation resulting in sepsis, a vicious cycle which can lead to severe inflammation, bowel necrosis, perforation, and death.
Toll-like receptor 4
The premature infant intestine is characterized by elevated expression of TLR4 on the intestinal epithelium35,36. TLRs play an essential role in the activation of innate immunity by recognizing specific patterns of microbial components37. TLR4 expression was increased in mice and humans with NEC38,39, and mutations in the TLR4 signaling pathways have been described in human NEC40–42. Additionally, TLR4 knockout mice were protected from NEC induction43. TLR4 is activated by lipopolysaccharides on Gram-negative bacteria36. Activation of TLR4 by intestinal lumen microbes results in barrier injury and impaired intestinal repair39, which consequently allows the translocation of the luminal bacteria, vasoconstriction, intestinal ischemia, and NEC44. TLR4 can also be inhibited by probiotic bacteria that activate TLR945 and can prevent goblet cell differentiation43, which are needed to maintain the physical mucous intestinal barrier to pathogenic bacteria.
Microvascular blood flow
NEC is a disease often characterized by areas of intestinal ischemia with insufficient blood supply. The development of NEC has been associated with generalized neonatal hypoxia and exchange transfusions46. Derangement of the intestinal microcirculation in NEC leads to areas of poor blood flow which may help facilitate the inflammatory cascade, resulting in intestinal injury47. Feeding and postprandial hypoxia have been shown to synergistically induce intestinal hypoxia in experimental NEC, highlighting the important balance between oxygen supply and demand48. The role of circulation in the pathogenesis of NEC continues to be a topic of research interest.
Microbiota
Dysbiosis is a disruption of gut microbiota development and its homeostasis, which has been associated with the development of NEC49. This pathological process involves a lack of beneficial commensal microbes combined with a low diversity of bacteria, which allows the overgrowth of pathogenic bacteria that induce an inflammatory response50. A meta-analysis of intestinal dysbiosis in preterm infants preceding NEC found an increased relative abundance of Proteobacteria and a decreased relative abundance of Firmicutes and Bacteroides51. Dysbiosis has been associated with the use of antibiotics and/or antacids in the NICU, formula feeding, and inflammatory response dysregulation52. NEC and matched control fecal samples tested for bacterial diversity and clustering showed that NEC patients tend to have less-diverse microbiomes and different distributions of the intestinal bacteria53–56. Proteobacteria may trigger a strong inflammatory response and colonization by anaerobic bacteria, which have been associated with NEC57. However, since Proteobacteria are also common constituents in the intestinal microbiome of preterm neonates who do not develop NEC, the role of microbiota remains unclear and represents only part of the complex pathogenesis58. While prophylactic probiotics have been shown to reduce the incidence of NEC when baseline incidence levels are high59, not all probiotic preparations are equally efficacious60. Comparing the efficacy of different strains, mixtures of multiple strains and long-term safety remain areas of current research61,62.
Intestinal stem cells and epithelial regeneration
The small intestinal epithelium renews every three to six days, a rate driven by vigorous proliferation within the intestinal crypts towards the villus tip63. Within the crypts there is a distinct stem cell zone containing intestinal stem cells (ISCs). ISCs are responsible for producing progenitor cells that differentiate into various types of epithelial cells including enterocytes, goblet cells, entero-endocrine cells, and Paneth cells64. ISCs are activated and replicate in response to intestinal injury. To measure the number of ISCs, leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5), a well-established wingless integrated (Wnt)-associated stem cell marker65, has been used. NEC has been characterized by a decrease in Lgr5-positive ISCs63,66, and restoration of ISC activity appears to have a beneficial effect66. The mechanism by which ISC viability is disrupted in NEC remains poorly understood and is currently being investigated.
Treatment strategies
Preventative treatments
Breast feeding has been shown to reduce the incidence of NEC relative to formula feeding59,67. In examining which components of breast milk help in reducing NEC incidence, breast milk-derived exosomes68 and human milk oligosaccharides (HMOs)69 were investigated using an experimental model of NEC. Breast milk-derived exosomes have been shown to promote intestinal epithelial cell viability and stimulate intestinal stem cell activity68. HMOs increased the number of goblet cells and mucin expression, stabilizing the intestinal barrier69. In infants with a birth weight of <1,500 grams, the use of prophylactic probiotics reduced the incidence of NEC (RR 0.34, 95% CI of 0.23–0.50)70, the risk of NEC-associated mortality (RR 0.56, 95% CI of 0.34–0.93)71, and the total length of hospital stay72. Notably, however, probiotic administration did not significantly reduce the risk of developing NEC in infants with a birth weight of <1,000 grams73 or the risk of developing NEC requiring surgery in infants of any size (RR 0.56, 95% CI of 0.56–1.25)70. Despite remaining uncertainties, the American Pediatric Surgical Association (APSA) Outcomes and Clinical Trials Committee Cochrane Review supports the prophylactic use of probiotics in preterm infants with a birth weight of <2,500 grams to reduce the risk of NEC in addition to the use of human breast milk rather than formula whenever possible70.
Medical and surgical treatments
Suspicion of NEC is frequently based on clinical presentation, which can include feeding intolerance, abdominal distention, bloody stools, emesis, and gastric retention. These signs lead to further workup including blood work to detect potential thrombocytopenia or metabolic acidosis and imaging studies to identify dilated loops of bowel, intestinal perforation, pneumatosis intestinalis, and portal venous gas. Depending on imaging findings and clinical presentation, surgical intervention is considered. Abdominal X-ray and ultrasound have been shown to be useful in helping to monitor the progression of the disease and detecting the presence of NEC74. In general, for Bell stage I (suspected NEC), supportive medical management alone is provided. For Bell stage II (proven NEC), medical management is usually tried first. This includes antibiotic treatment, nasogastric decompression, and total parenteral nutrition. If the patient fails to respond to medical treatment, surgical management is considered75. Patients with Bell stage III (advanced NEC) can be treated medically and may require inotropic support. However, neonates who develop intestinal perforation, have suspected bowel necrosis, or fail to respond to medical treatment require surgical treatment. Among VLBW infants, 27–52% require surgical intervention76.
Future directions
Current research using both animal models and human tissue has yielded novel potential therapeutic avenues (Table 3). For example, the prospects of using stem cell therapy77 and breast-milk derived exosomes68 appear to be promising. Amniotic fluid stem cells given by intraperitoneal injection migrated to the intestinal villi and colonized almost exclusively the damaged intestine of NEC rat pups, where they promoted auto-regeneration of the intestinal epithelium78. Stem cell-derived exosomes have also reduced the incidence and severity of experimental NEC79. In addition, milk-derived exosomes have recently been shown to reduce intestinal epithelial injury68. Safety and efficacy trials still need to take place before some of these potential treatments may become clinically available. Considering the lack of improvement and the unchanged mortality associated with NEC, it is promising to see that several avenues are being explored in both disease prevention and treatment.
Table 3. Future potential therapy for necrotizing enterocolitis.
Breast milk component (human milk oligosaccharides or exosomes) administration |
| Prophylactic probiotics |
| Stem cell administration |
Grant information
This work is supported by a Canadian Institutes of Health Research (CIHR) Foundation Grant 353857. AP is the Robert M. Filler Chair of Surgery at The Hospital for Sick Children (HSC).
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
F1000 recommendedReferences
- 1.
Neu J, Walker WA:
Necrotizing enterocolitis.
N Engl J Med.
2011; 364(3): 255–64. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 2.
Thompson AM, Bizzarro MJ:
Necrotizing enterocolitis in newborns: pathogenesis, prevention and management.
Drugs.
2008; 68(9): 1227–38. PubMed Abstract
| Publisher Full Text
- 3.
Cotten CM, Oh W, McDonald S, et al.:
Prolonged hospital stay for extremely premature infants: risk factors, center differences, and the impact of mortality on selecting a best-performing center.
J Perinatol.
2005; 25(10): 650–5. PubMed Abstract
| Publisher Full Text
- 4.
Luig M, Lui K, NSW & ACT NICUS Group:
Epidemiology of necrotizing enterocolitis--Part II: Risks and susceptibility of premature infants during the surfactant era: a regional study.
J Paediatr Child Health.
2005; 41(4): 174–9. PubMed Abstract
| Publisher Full Text
- 5.
Fitzgibbons SC, Ching Y, Yu D, et al.:
Mortality of necrotizing enterocolitis expressed by birth weight categories.
J Pediatr Surg.
2009; 44(6): 1072–5; discussion 1075-6. PubMed Abstract
| Publisher Full Text
- 6.
Gordon PV, Swanson JR, Attridge JT, et al.:
Emerging trends in acquired neonatal intestinal disease: is it time to abandon Bell's criteria?
J Perinatol.
2007; 27(11): 661–71. PubMed Abstract
| Publisher Full Text
- 7.
Sonntag J, Wagner MH, Waldschmidt J, et al.:
Multisystem organ failure and capillary leak syndrome in severe necrotizing enterocolitis of very low birth weight infants.
J Pediatr Surg.
1998; 33(3): 481–4. PubMed Abstract
| Publisher Full Text
- 8.
Battersby C, Santhalingam T, Costeloe K, et al.:
Incidence of neonatal necrotising enterocolitis in high-income countries: a systematic review.
Arch Dis Child Fetal Neonatal Ed.
2018; 103(2): F182–F189. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 9.
Kosloske AM:
Epidemiology of necrotizing enterocolitis.
Acta Paediatr Suppl.
1994; 396: 2–7. PubMed Abstract
| Publisher Full Text
- 10.
Wójkowska-Mach J, Różańska A, Borszewska-Kornacka M, et al.:
Necrotising enterocolitis in preterm infants: epidemiology and antibiotic consumption in the Polish neonatology network neonatal intensive care units in 2009.
PLoS One.
2014; 9(3): e92865. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 11.
Rose AT, Patel RM:
A critical analysis of risk factors for necrotizing enterocolitis.
Semin Fetal Neonatal Med.
2018; 23(6): 374–9. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 12.
Samuels N, van de Graaf RA, de Jonge RCJ, et al.:
Risk factors for necrotizing enterocolitis in neonates: a systematic review of prognostic studies.
BMC Pediatr.
2017; 17(1): 105. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 13.
Travers CP, Clark RH, Spitzer AR, et al.:
Exposure to any antenatal corticosteroids and outcomes in preterm infants by gestational age: prospective cohort study.
BMJ.
2017; 356; j1039. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 14.
Been JV, Lievense S, Zimmermann LJ, et al.:
Chorioamnionitis as a risk factor for necrotizing enterocolitis: a systematic review and meta-analysis.
J Pediatr.
2013; 162(2): 236–42.e2. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 15.
Lu Q, Cheng S, Zhou M, et al.:
Risk Factors for Necrotizing Enterocolitis in Neonates: A Retrospective Case-Control Study.
Pediatr Neonatol.
2017; 58(2): 165–70. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 16.
Czyrko C, Del Pin CA, O'Neill JA Jr, et al.:
Maternal cocaine abuse and necrotizing enterocolitis: outcome and survival.
J Pediatr Surg.
1991; 26(4): 414–8; discussion 419-21. PubMed Abstract
| Publisher Full Text
- 17.
Downard CD, Grant SN, Maki AC, et al.:
Maternal cigarette smoking and the development of necrotizing enterocolitis.
Pediatrics.
2012; 130(1): 78–82. PubMed Abstract
| Publisher Full Text
- 18.
Denning NL, Prince JM:
Neonatal intestinal dysbiosis in necrotizing enterocolitis.
Mol Med.
2018; 24(1): 4. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 19.
Mueller NT, Bakacs E, Combellick J, et al.:
The infant microbiome development: mom matters.
Trends Mol Med.
2015; 21(2): 109–17. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 20.
Safe M, Chan WH, Leach ST, et al.:
Widespread use of gastric acid inhibitors in infants: Are they needed? Are they safe?
World J Gastrointest Pharmacol Ther.
2016; 7(4): 531–539. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 21.
Singh R, Visintainer PF, Frantz ID 3rd, et al.:
Association of necrotizing enterocolitis with anemia and packed red blood cell transfusions in preterm infants.
J Perinatol.
2011; 31(3): 176–82. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 22.
Herrera C, Holberton J, Davis P:
Prolonged versus short course of indomethacin for the treatment of patent ductus arteriosus in preterm infants.
Cochrane Database Syst Rev.
2007; (2): CD003480. PubMed Abstract
| Publisher Full Text
- 23.
Jain A, Shah PS:
Diagnosis, Evaluation, and Management of Patent Ductus Arteriosus in Preterm Neonates.
JAMA Pediatr.
2015; 169(9): 863–72. PubMed Abstract
| Publisher Full Text
- 24.
Yee WH, Scotland J, Evidence-based Practice for Improving Quality (EPIQ) Evidence Review Group:
Does primary surgical closure of the patent ductus arteriosus in infants <1500 g or ≤32 weeks’ gestation reduce the incidence of necrotizing enterocolitis?
Paediatr Child Health.
2012; 17(3): 125–8. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 25.
Zhang C, Sherman MP, Prince LS, et al.:
Paneth cell ablation in the presence of Klebsiella pneumoniae induces necrotizing enterocolitis (NEC)-like injury in the small intestine of immature mice.
Dis Model Mech.
2012; 5(4): 522–32. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 26.
Molteni M, Gemma S, Rossetti C:
The Role of Toll-Like Receptor 4 in Infectious and Noninfectious Inflammation.
Mediators Inflamm.
2016; 2016: 6978936. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 27.
De Plaen IG:
Inflammatory signaling in necrotizing enterocolitis.
Clin Perinatol.
2013; 40(1): 109–24. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 28.
Schnabl KL, Van Aerde JE, Thomson AB, et al.:
Necrotizing enterocolitis: a multifactorial disease with no cure.
World J Gastroenterol.
2008; 14(14): 2142–61. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 29.
Claud EC, Keegan KP, Brulc JM, et al.:
Bacterial community structure and functional contributions to emergence of health or necrotizing enterocolitis in preterm infants.
Microbiome.
2013; 1(1): 20. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 30.
Watkins DJ, Besner GE:
The role of the intestinal microcirculation in necrotizing enterocolitis.
Semin Pediatr Surg.
2013; 22(2): 83–7. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 31.
Nowicki PT, Reber KM, Giannone PJ, et al.:
Intestinal O2 consumption in necrotizing enterocolitis: role of nitric oxide.
Pediatr Res.
2006; 59(4 Pt 1): 500–5. PubMed Abstract
| Publisher Full Text
- 32.
Ford H, Watkins S, Reblock K, et al.:
The role of inflammatory cytokines and nitric oxide in the pathogenesis of necrotizing enterocolitis.
J Pediatr Surg.
1997; 32(2): 275–82. PubMed Abstract
| Publisher Full Text
- 33.
Ciftci I, Ozdemir M, Aktan M, et al.:
Bacterial translocation and intestinal injury in experimental necrotizing enterocolitis model.
Bratisl Lek Listy.
2012; 113(4): 206–10. PubMed Abstract
| Publisher Full Text
- 34.
Aceti A, Beghetti I, Martini S, et al.:
Oxidative Stress and Necrotizing Enterocolitis: Pathogenetic Mechanisms, Opportunities for Intervention, and Role of Human Milk.
Oxid Med Cell Longev.
2018; 2018: 7397659. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 35.
Kuzmich NN, Sivak KV, Chubarev VN, et al.:
TLR4 Signaling Pathway Modulators as Potential Therapeutics in Inflammation and Sepsis.
Vaccines (Basel).
2017; 5(4): pii: E34. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 36.
Hackam DJ, Sodhi CP:
Toll-Like Receptor-Mediated Intestinal Inflammatory Imbalance in the Pathogenesis of Necrotizing Enterocolitis.
Cell Mol Gastroenterol Hepatol.
2018; 6(2): 229–238.e1. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 37.
Takeda K, Akira S:
TLR signaling pathways.
Semin Immunol.
2004; 16(1): 3–9. PubMed Abstract
| Publisher Full Text
- 38.
Egan CE, Sodhi CP, Good M, et al.:
Toll-like receptor 4-mediated lymphocyte influx induces neonatal necrotizing enterocolitis.
J Clin Invest.
2016; 126(2): 495–508. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 39.
Leaphart CL, Cavallo J, Gribar SC, et al.:
A critical role for TLR4 in the pathogenesis of necrotizing enterocolitis by modulating intestinal injury and repair.
J Immunol.
2007; 179(7): 4808–20. PubMed Abstract
| Publisher Full Text
- 40.
Sampath V, Menden H, Helbling D, et al.:
SIGIRR genetic variants in premature infants with necrotizing enterocolitis.
Pediatrics.
2015; 135(6): e1530–4. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 41.
Fawley J, Cuna A, Menden HL, et al.:
Single-Immunoglobulin Interleukin-1-Related Receptor regulates vulnerability to TLR4-mediated necrotizing enterocolitis in a mouse model.
Pediatr Res.
2017; 83(1–1): 164–74. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 42.
Ganguli K, Meng D, Rautava S, et al.:
Probiotics prevent necrotizing enterocolitis by modulating enterocyte genes that regulate innate immune-mediated inflammation.
Am J Physiol Gastrointest Liver Physiol.
2013; 304(2): G132–G141. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 43.
Sodhi CP, Neal MD, Siggers R, et al.:
Intestinal epithelial Toll-like receptor 4 regulates goblet cell development and is required for necrotizing enterocolitis in mice.
Gastroenterology.
2012; 143(3): 708–718.e5. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 44.
Lu P, Sodhi CP, Hackam DJ:
Toll-like receptor regulation of intestinal development and inflammation in the pathogenesis of necrotizing enterocolitis.
Pathophysiology.
2014; 21(1): 81–93. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 45.
de Kivit S, Tobin MC, Forsyth CB, et al.:
Regulation of Intestinal Immune Responses through TLR Activation: Implications for Pro- and Prebiotics.
Front Immunol.
2014; 5: 60. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 46.
Beeby PJ, Jeffery H:
Risk factors for necrotising enterocolitis: the influence of gestational age.
Arch Dis Child.
1992; 67(4 Spec No): 432–5. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 47.
Young CM, Kingma SD, Neu J:
Ischemia-reperfusion and neonatal intestinal injury.
J Pediatr.
2011; 158(2 Suppl): e25–8. PubMed Abstract
| Publisher Full Text
- 48.
Chen Y, Koike Y, Miyake H, et al.:
Formula feeding and systemic hypoxia synergistically induce intestinal hypoxia in experimental necrotizing enterocolitis.
Pediatr Surg Int.
2016; 32(12): 1115–9. PubMed Abstract
| Publisher Full Text
- 49.
Cho I, Blaser MJ:
The human microbiome: at the interface of health and disease.
Nat Rev Genet.
2012; 13(4): 260–70. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 50.
Patel RM, Denning PW:
Intestinal microbiota and its relationship with necrotizing enterocolitis.
Pediatr Res.
2015; 78(3): 232–8. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 51.
Pammi M, Cope J, Tarr PI, et al.:
Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis.
Microbiome.
2017; 5(1): 31. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 52.
Cassir N, Simeoni U, La Scola B:
Gut microbiota and the pathogenesis of necrotizing enterocolitis in preterm neonates.
Future Microbiol.
2016; 11(2): 273–92. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 53.
Wang Y, Hoenig JD, Malin KJ, et al.:
16S rRNA gene-based analysis of fecal microbiota from preterm infants with and without necrotizing enterocolitis.
ISME J.
2009; 3(8): 944–54. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 54.
Mai V, Young CM, Ukhanova M, et al.:
Fecal microbiota in premature infants prior to necrotizing enterocolitis.
PLoS One.
2011; 6(6): e20647. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 55.
Morrow AL, Lagomarcino AJ, Schibler KR, et al.:
Early microbial and metabolomic signatures predict later onset of necrotizing enterocolitis in preterm infants.
Microbiome.
2013; 1(1): 13. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 56.
Torrazza RM, Ukhanova M, Wang X, et al.:
Intestinal microbial ecology and environmental factors affecting necrotizing enterocolitis.
PLoS One.
2013; 8(12): e83304. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 57.
Torrazza RM, Neu J:
The altered gut microbiome and necrotizing enterocolitis.
Clin Perinatol.
2013; 40(1): 93–108. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 58.
La Rosa PS, Warner BB, Zhou Y, et al.:
Patterned progression of bacterial populations in the premature infant gut.
Proc Natl Acad Sci U S A.
2014; 111(34): 12522–7. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 59.
Hackam DJ, Good M, Sodhi CP:
Mechanisms of gut barrier failure in the pathogenesis of necrotizing enterocolitis: Toll-like receptors throw the switch.
Semin Pediatr Surg.
2013; 22(2): 76–82. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 60.
Patel RM, Underwood MA:
Probiotics and necrotizing enterocolitis.
Semin Pediatr Surg.
2018; 27(1): 39–46. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 61.
Chang HY, Chen JH, Chang JH, et al.:
Multiple strains probiotics appear to be the most effective probiotics in the prevention of necrotizing enterocolitis and mortality: An updated meta-analysis.
PLoS One.
2017; 12(2): e0171579. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 62.
Dermyshi E, Wang Y, Yan C, et al.:
The "Golden Age" of Probiotics: A Systematic Review and Meta-Analysis of Randomized and Observational Studies in Preterm Infants.
Neonatology.
2017; 112(1): 9–23. PubMed Abstract
| Publisher Full Text
| F1000 Recommendation
- 63.
Gassler N:
Paneth cells in intestinal physiology and pathophysiology.
World J Gastrointest Pathophysiol.
2017; 8(4): 150–60. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 64.
Umar S:
Intestinal stem cells.
Curr Gastroenterol Rep.
2010; 12(5): 340–8. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 65.
Khan Z, Orr A, Michalopoulos GK, et al.:
Immunohistochemical Analysis of the Stem Cell Marker LGR5 in Pediatric Liver Disease.
Pediatr Dev Pathol.
2017; 20(1): 16–27. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 66.
Niño DF, Sodhi CP, Egan CE, et al.:
Retinoic Acid Improves Incidence and Severity of Necrotizing Enterocolitis by Lymphocyte Balance Restitution and Repopulation of LGR5+ Intestinal Stem Cells.
Shock.
2017; 47(1): 22–32. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 67.
Herrmann K, Carroll K:
An exclusively human milk diet reduces necrotizing enterocolitis.
Breastfeed Med.
2014; 9(4): 184–90. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 68.
Hock A, Miyake H, Li B, et al.:
Breast milk-derived exosomes promote intestinal epithelial cell growth.
J Pediatr Surg.
2017; 52(5): 755–9. PubMed Abstract
| Publisher Full Text
- 69.
Wu RY, Li B, Koike Y, et al.:
Human Milk Oligosaccharides Increase Mucin Expression in Experimental Necrotizing Enterocolitis.
Mol Nutr Food Res.
2018; e1800658. PubMed Abstract
| Publisher Full Text
- 70.
Downard CD, Renaud E, St Peter SD, et al.:
Treatment of necrotizing enterocolitis: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee systematic review.
J Pediatr Surg.
2012; 47(11): 2111–22. PubMed Abstract
| Publisher Full Text
- 71.
Rees CM, Hall NJ, Fleming P, et al.:
Probiotics for the prevention of surgical necrotising enterocolitis: systematic review and meta-analysis.
BMJ Paediatr Open.
2017; 1(1): e000066. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 72.
Aceti A, Gori D, Barone G, et al.:
Probiotics and Time to Achieve Full Enteral Feeding in Human Milk-Fed and Formula-Fed Preterm Infants: Systematic Review and Meta-Analysis.
Nutrients.
2016; 8(8): pii: E471. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 73.
Sawh SC, Deshpande S, Jansen S, et al.:
Prevention of necrotizing enterocolitis with probiotics: a systematic review and meta-analysis.
PeerJ.
2016; 4: e2429. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 74.
Janssen Lok M, Miyake H, Hock A, et al.:
Value of abdominal ultrasound in management of necrotizing enterocolitis: a systematic review and meta-analysis.
Pediatr Surg Int.
2018; 34(6): 589–612. PubMed Abstract
| Publisher Full Text
- 75.
Rees CM, Hall NJ, Eaton S, et al.:
Surgical strategies for necrotising enterocolitis: a survey of practice in the United Kingdom.
Arch Dis Child Fetal Neonatal Ed.
2005; 90(2): F152–5. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 76.
Robinson JR, Rellinger EJ, Hatch LD, et al.:
Surgical necrotizing enterocolitis.
Semin Perinatol.
2017; 41(1): 70–9. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
- 77.
Drucker NA, McCulloh CJ, Li B, et al.:
Stem cell therapy in necrotizing enterocolitis: Current state and future directions.
Semin Pediatr Surg.
2018; 27(1): 57–64. PubMed Abstract
| Publisher Full Text
| Free Full Text
- 78.
Zani A, Cananzi M, Fascetti-Leon F, et al.:
Amniotic fluid stem cells improve survival and enhance repair of damaged intestine in necrotising enterocolitis via a COX-2 dependent mechanism.
Gut.
2013; 63(2): 300–9. PubMed Abstract
| Publisher Full Text
- 79.
McCulloh CJ, Olson JK, Wang Y, et al.:
Treatment of experimental necrotizing enterocolitis with stem cell-derived exosomes.
J Pediatr Surg.
2018; 53(6): 1215–20. PubMed Abstract
| Publisher Full Text
| Free Full Text
| F1000 Recommendation
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