Necrotising Enterocolitis - Podcast Version TeachMePaediatrics 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x Necrotising enterocolitis (NEC) is among the most common neonatal surgical emergencies1 and has significant morbidity and mortality. 2 It is characterised by variable injury to the intestines, ranging from mucosal damage to necrosis and perforation. 3 Epidemiology The incidence of NEC is 1-3/1000 live births. This increases to 5-10% in very low birth weight (VLBW) infants.1 90% of cases occur in preterm infants, while the incidence is reduced 6-fold in breastfed infants.1 The mortality rate associated with NEC is estimated to be between 20-30% depending on severity.4 Complications occur post-surgery in about 27% of infants with surgical NEC, while about 3% are discharged before 28-days post-decision to intervene surgically.8 Pathophysiology The pathophysiology of NEC is yet to be understood entirely. Still, it is likely due to an innate immune response to the microbiota of the premature infant’s gut, thereby leading to inflammation and injury.5 Genetic predisposition and microvascular tone imbalance have also been suggested to be contributing factors.4 Risk factors1 Prematurity or very low birth weight (VLBW) Formula feeding Intrauterine growth restriction (IUGR) Polycythaemia Exchange transfusion Hypoxia By TeachMeSeries Ltd (2026) Figure 1- Risk factors for necrotising enterocolitis Clinical Features The classic presentation of NEC includes feeding intolerance, vomiting (may be bile or blood-stained), abdominal distention and haematochezia.2,3 As NEC progresses, features include abdominal tenderness, abdominal oedema, erythema and palpable bowel loops (due to loop dilation). In addition to gastrointestinal features, NEC also presents with systemic features such as apnoea, lethargy, bradycardia and decreased peripheral perfusion.3 Differential diagnosis Due to the non-specific presentation of NEC, its differential diagnosis is broad. Differentials to consider include: Neonatal sepsis Hirschsprung disease Intestinal malrotation Intestinal volvulus Gastroesophageal reflux Spontaneous intestinal perforation Infectious enterocolitis3 Investigations Imaging Plain abdominal radiography is the diagnostic imaging for NEC. Features include distended bowel loops, thickened bowel wall (bowel oedema), intramural gas (pneumatosis intestinalis), gas in the portal tract and pneumoperitoneum in the later stages due to bowel perforation.3,4 By TeachMeSeries Ltd (2026) Figure 2- Abdominal x-ray findings in necrotising enterocolitis2 Laboratory tests Full blood count- anaemia, thrombocytopenia and leukocytosis/leukopenia are often present. U & Es- hyponatraemia Blood gas- metabolic acidosis Blood culture- to rule out sepsis Staging NEC is staged according to the Bell scoring system based on clinical features and abdominal x-ray features:1,6 Bell’s Stage Severity Clinical features Radiological features Stage I Suspected NEC Systemic: Lethargy, temperature instability, apnoea, bradycardia. Intestinal: Emesis, abdominal distension, haematochezia Bowel distension only. Stage II Definite NEC As in Stage I plus: Systemic: metabolic acidosis, thrombocytopenia Intestinal: abdominal tenderness, absent bowel signs Bowel distension Portal venous gas Pneumatosis intestinalis Stage III Advanced NEC As in Stage I and II plus: Systemic: severe acidosis, electrolyte abnormalities, thrombocytopenia, DIC. Intestinal: Marked GI bleeding As in Stage II plus pneumoperitoneum Management Prophylaxis NEC can be prevented by administering antenatal steroids if premature delivery is anticipated.1 Breastfeeding is a protective factor.1 Research has also shown that probiotics reduce the risk of NEC.1 Medical Management Suitable for most infants with Bell Stage I and Stage II NEC and includes the following: Withhold oral feeds for 10-14 days and replace with parenteral nutrition. IV antibiotics for 10-14 days based on local protocols. Systemic support in the form of ventilatory support, fluid resuscitation, inotropic support, correction of acid-base balance coagulopathy and/or thrombocytopenia.1,7 Surgical Management Indications for surgery for NEC include: Intestinal perforation GI obstruction secondary to stricture formation Deterioration despite medical management1,7 Different surgical methods exist for NEC management depending on the extent of the disease. The most common procedure carried out for NEC is intestinal resection with stoma formation.8 Other procedures include resection with primary anastomosis, stoma formation without resection, clip and drop with resection, open and close laparotomy and negative initial laparotomy.8 The need to perform a clip and drop procedure is associated with increased 28-day mortality.8 Some infants undergo peritoneal drainage, but most subsequently require laparotomy.8 Complications Immediate complications of NEC include intestinal perforation, sepsis and death. 50% of patients that survive NEC develop long-term complications.3 The most common long-term complications are intestinal stricture and short-bowel syndrome.3 Other long-term complications include neurodevelopmental disorders and NEC recurrence.3 References No. Reference 1 Tasker RC, McCLure RJ, Acerini CL. Oxford handbook of paediatrics. 2nd ed. England: Oxford University Press; 2013. 2 Lissauer T. Illustrated textbook of paediatrics. 5th ed. London: Elsevier Science; 2018. 176 p. 3 Springer SC, Annibal DJ. Necrotizing Enterocolitis. [Internet] [Updated 2017 Dec 27]. Available from: https://emedicine.medscape.com/article/977956-overview 4 Neu J, Walker WA. Necrotizing enterocolitis. The New England journal of medicine. [Internet] 2011; 364(3): 255–264. Available from: https://doi.org/10.1056/NEJMra1005408 5 Tanner SM, Berryhill TF, Ellenburg JL, Jilling T, Cleveland DS, Lorenz RG, Martin CA. Pathogenesis of necrotising enterocolitis: modeling the innate immune response. The American journal of pathology [Internet] 2015; 185(1): 4–16. Available from: https://doi.org/10.1016/j.ajpath.2014.08.028 6 Sheik Y, Gaillard, F. Necrotising enterocolitis (staging). [Internet] Available from: https://radiopaedia.org/articles/necrotising-enterocolitis-staging-1 7 Zani A, Pierro A. Necrotising enterocolitis: controversies and challenges. F1000 Research [Internet] 2015; 4. Available from: https://doi.org/10.12688/f1000research.6888.1 8 Patel RM, Denning PW. Intestinal microbiota and its relationship with necrotizing enterocolitis. Paediatric research [Internet] 2015; 78: 232-238. Available from https://doi.org/10.1038/pr.2015.97 Do you think you’re ready? Take the quiz below Pro Feature - Quiz Necrotising Enterocolitis Question 1 of 3 Submitting... Skip Next Rate question: You scored 0% Skipped: 0/3 1000+ More Questions Available Upgrade to TeachMePaediatrics Pro Challenge yourself with over 1000 multiple-choice questions to reinforce learning Learn More Frequent questions What is necrotising enterocolitis (NEC)? Necrotising enterocolitis (NEC) is a severe neonatal condition characterised by inflammation and damage to the intestines, which can lead to necrosis and perforation. It is most commonly seen in preterm infants and can result in significant morbidity and mortality. What are the common clinical features of NEC? The typical symptoms of NEC include feeding intolerance, vomiting (which may be bile or blood-stained), abdominal distention, and the presence of blood in the stool. As the condition progresses, additional symptoms such as abdominal tenderness and systemic signs like lethargy and bradycardia may develop. What are the risk factors associated with necrotising enterocolitis? Key risk factors for NEC include prematurity, very low birth weight (VLBW), formula feeding, and intrauterine growth restriction (IUGR). Other contributing factors may include polycythaemia, exchange transfusion, and hypoxia. How is necrotising enterocolitis diagnosed? Diagnosis of NEC primarily involves plain abdominal radiography, which reveals signs such as distended bowel loops, thickened bowel walls, and pneumatosis intestinalis. Laboratory tests may also indicate abnormalities like anaemia and metabolic acidosis. What are the treatment options for necrotising enterocolitis? Management of NEC varies by severity; medical treatment includes withholding oral feeds and administering intravenous antibiotics, while surgical intervention may be necessary for intestinal perforation or obstruction. Surgical options often involve intestinal resection with potential stoma formation, depending on the extent of the disease. Rate This Article