Paeds · fetal-neonatal-and-perinatal
Necrotising enterocolitis and spontaneous intestinal perforation
Also known as Necrotising enterocolitis · NEC · Spontaneous intestinal perforation · Focal intestinal perforation · Neonatal bowel perforation
Fellowship guide to the two neonatal intestinal emergencies that end in bowel perforation: necrotising enterocolitis (NEC) and spontaneous intestinal perforation (SIP). Covers modified Bell staging, the dysbiosis-inflammation pathophysiology of NEC versus the focal muscularis injury of SIP, radiograph interpretation, the medical bundle, the surgical triggers and the peritoneal-drainage-versus-laparotomy decision, and the prevention bundle.
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Target exams
Red flags
- Preterm infant with bilious aspirates, abdominal distension and systemic instability
- Abdominal wall erythema, discolouration or a palpable fixed loop
- Pneumatosis intestinalis or portal venous gas on abdominal radiograph
- Sudden pneumoperitoneum or a 'silvery abdomen' in a deteriorating infant
- Thrombocytopenia, metabolic acidosis and shock in a feeding preterm infant
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- Neonatal gastrointestinal emergencies: recognition of NEC
- Feeding intolerance and abdominal signs in the preterm infant
- Resuscitation of the deteriorating neonate
- NEC and spontaneous intestinal perforation: pathophysiology, modified Bell staging and management
- Neonatal surgical decision-making: medical versus surgical NEC, PD versus laparotomy
- Prevention of NEC: human milk, feeding protocols, probiotics, antenatal steroids
- Applied neonatal gut physiology and the dysbiosis-inflammation model of NEC
- Surgical decision triggers in NEC: pneumoperitoneum, fixed loop, paracentesis
- Evidence base for human milk and probiotics in NEC prevention
- Short case: the deteriorating preterm with suspected NEC
- Communication: counselling parents after a diagnosis of NEC totalis or SIP
- Neonatology: necrotising enterocolitis and bowel perforation
- Neonatal surgery: the acutely unwell neonate with abdominal signs
- Evidence-based feeding and nutrition of the preterm infant
- Neonatal gut pathophysiology: dysbiosis, TLR4 signalling and pneumatosis
- Pharmacology and therapeutics: antibiotic choice and probiotic controversy
- Radiology: pneumatosis, portal venous gas and pneumoperitoneum
- Neonatal NEC/SIP scenario station
- Communication: breaking difficult news in neonatal surgery
- Necrotising enterocolitis: recognition, staging and management
- Neonatal surgical emergencies: intestinal perforation
- Prevention of NEC and nutrition of the preterm infant
- Patient Care: management of suspected NEC and intestinal perforation
- Medical Knowledge: NEC pathophysiology and the NEC-versus-SIP distinction
- Systems-Based Practice: neonatal retrieval and tertiary surgical NICU coordination
- Medical Expert: necrotising enterocolitis and spontaneous intestinal perforation
- Collaborator: neonatologist-surgeon decision-making in bowel perforation
- Health Advocate: human-milk-based prevention and equity of neonatal surgical access
Overview & Definition
A 26-week, 780 g infant on day 9 of life, established on enteral formula feeds, develops increasing gastric residuals, a distended and tender abdomen, and apnoeic spells. The abdominal radiograph shows bubbly lucency in the bowel wall. This is necrotising enterocolitis (NEC) — the archetypal inflammatory necrosis of the immature intestine, and one of the few remaining killers of preterm infants that prevention, not treatment, has substantially changed. [3]
NEC is defined as transmural inflammatory necrosis of the bowel wall with a characteristic radiological and clinical signature: pneumatosis intestinalis (gas in the bowel wall), a septic systemic course, and a predilection for the terminal ileum and proximal colon. It is overwhelmingly a disease of the preterm infant — prematurity is the single strongest risk factor — and it typically declares itself between the second day and the end of the first month of life, almost always after enteral feeding has begun. [3] [8]
Spontaneous intestinal perforation (SIP), also called focal intestinal perforation, is a separate entity that produces the same dramatic finding — free air in the abdomen — by a different mechanism. It is a single, isolated, often pinpoint perforation, usually at the anti-mesenteric border of the terminal ileum, with little or no surrounding necrosis and minimal inflammation. The infant is frequently haemodynamically stable, and the perforation is often an incidental finding on a radiograph taken for another reason. SIP is concentrated in the extremely-low-birth-weight (ELBW) infant and has become, in some networks, the commonest surgical bowel lesion in that group. [7] [12]
The two are taught together for one reason: both culminate in bowel perforation, and telling them apart at the cot-side changes prognosis, surgical strategy, and counselling. NEC is a disease of the bowel wall that you must stop feeding, treat medically, and operate on for the complication of perforation. SIP is a hole in a focally weak wall that you can often drain and close without the septic inflammation that defines NEC. [7] [13]
References13ShowHide
- [1]Bell MJ Neonatal necrotizing enterocolitis. Therapeutic decisions based upon clinical staging. Ann Surg, 1978.PMID 413500
- [2]Walsh MC Necrotizing enterocolitis: treatment based on staging criteria. Pediatr Clin North Am, 1986.PMID 3081865
- [3]Neu J Necrotizing enterocolitis. N Engl J Med, 2011.PMID 21247316
- [4]Rees CM Peritoneal drainage or laparotomy for neonatal bowel perforation? A randomized controlled trial. Ann Surg, 2008.PMID 18580206
- [5]Rees CM Peritoneal drainage does not stabilize extremely low birth weight infants with perforated bowel: data from the NET Trial. J Pediatr Surg, 2010.PMID 20152345
- [6]Quigley M Donor human milk for preventing necrotising enterocolitis in very preterm or very low-birthweight infants. Cochrane Database Syst Rev, 2024.PMID 39239939
- [7]Swanson JR Spontaneous intestinal perforation (SIP) will soon become the most common form of surgical bowel disease in the extremely low birth weight infant. J Perinatol, 2022.PMID 35177793
- [8]Gordon PV Can a national dataset generate a nomogram for necrotizing enterocolitis onset? J Perinatol, 2014.PMID 25078862
- [9]Abdullahi AM Efficacy of probiotic supplementation in preventing necrotizing enterocolitis in preterm infants: a systematic review and meta-analysis. J Matern Fetal Neonatal Med, 2025.PMID 40204632
- [10]Kulkarni T Probiotic sepsis in preterm neonates - a systematic review. Eur J Pediatr, 2022.PMID 35348825
- [11]Attridge JT New insights into spontaneous intestinal perforation using a national data set (3): antenatal steroids have no adverse association with spontaneous intestinal perforation. J Perinatol, 2006.PMID 17024144
- [12]Gordon PV Understanding clinical literature relevant to spontaneous intestinal perforations. Am J Perinatol, 2009.PMID 19067283
- [13]Bethell GS Surgeons and neonatologists views about surgical decision-making in necrotising enterocolitis. Arch Dis Child Fetal Neonatal Ed, 2025.PMID 40280739