# Necrotising Enterocolitis

> Necrotising enterocolitis for NEET-PG Paediatrics covering Bell staging, pneumatosis and portal venous gas, and medical versus surgical care in preterm infants.

- Canonical URL: https://prepelephant.com/topics/neet-pg/paediatrics/necrotising-enterocolitis
- Exam / course: NEET-PG · Subject: Paediatrics
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-14
- Last updated: 2026-10-14
- Reference basis: Nelson Textbook of Pediatrics; Avery's Diseases of the Newborn; IAP Textbook of Pediatrics
- How to cite: "Necrotising Enterocolitis", PrepElephant, https://prepelephant.com/topics/neet-pg/paediatrics/necrotising-enterocolitis

## Direct answer

Necrotising enterocolitis is an acute inflammatory injury of the intestine that mainly affects preterm infants, causing bowel necrosis, perforation and sepsis. Pneumatosis intestinalis, which is gas within the bowel wall on abdominal X-ray, is the key sign that confirms the diagnosis. Early disease is managed medically, with feeds stopped, the stomach decompressed and antibiotics given, while perforation or progressive necrosis calls for surgery.

## What you must remember

- **Main risk group:** preterm infants, especially those with very low birth weight, the strongest single risk factor.
- **Other risks:** formula feeding, perinatal asphyxia, sepsis, and a patent ductus arteriosus with hypoperfusion of the gut.
- **Early signs:** feed intolerance, abdominal distension, bilious aspirates, blood in the stools, apnoea and lethargy.
- **Radiological signs:** pneumatosis intestinalis confirms the diagnosis; portal venous gas indicates severe disease, and free air under the diaphragm indicates perforation.
- **Staging:** the modified Bell staging system grades suspected, definite and advanced disease, and it guides the decision to treat medically or operate.
- **Medical care:** nil by mouth, nasogastric decompression, intravenous antibiotics covering enteric organisms, parenteral nutrition and monitoring of acid-base status, platelets and blood glucose.
- **Prevention:** human milk feeding, slow and cautious advancement of feeds, and avoidance of sepsis and hypoxia in the preterm baby.

## Bell staging and the decision to operate

Bell staging is the classification examiners test most often, because the stage decides the treatment. The table grades disease by its clinical, radiological and systemic features, and each stage carries a different plan.

| Bell stage | Key features | Management |
|---|---|---|
| Stage I, suspected | Feed intolerance, mild distension, nonspecific X-ray | Nil by mouth, nasogastric tube and antibiotics |
| Stage II, definite | Pneumatosis, ileus, mild acidosis or thrombocytopenia | Continued medical care with close monitoring |
| Stage III, advanced | Perforation, pneumoperitoneum, shock or DIC | Resuscitation and urgent surgical review |

A finding of free air on X-ray, or a sudden deterioration in a baby with Stage III disease, points towards surgery. Because the stage can change within hours, the team reassesses the baby and repeats abdominal films as the clinical picture evolves.

Surgical timing is a joint decision by the neonatologist and the paediatric surgeon, who review the same films together, and a baby with perforation is not kept on medical therapy alone.

## Where the exam tries to catch you

Necrotising enterocolitis stems usually test the radiological sign and the indications for surgery.

- **Trap:** taking a normal first abdominal X-ray as proof that necrotising enterocolitis is absent. — **Correct:** early films can look normal or nonspecific, so the baby needs repeat films and clinical reassessment.
- **Trap:** choosing laparotomy as first-line treatment for every baby with suspected disease. — **Correct:** most babies with Bell stage II are managed medically, and surgery is reserved for perforation or failure of medical care.
- **Trap:** restarting feeds early to prevent a stricture. — **Correct:** feeds are held while the bowel is inflamed, and reintroduction follows clinical and radiological recovery.

## Frequently asked questions

### Which radiological sign confirms necrotising enterocolitis?

Pneumatosis intestinalis, which is gas within the bowel wall, is the key radiological sign that confirms necrotising enterocolitis. Portal venous gas indicates more advanced disease, while free gas under the diaphragm indicates perforation.

### Which infants are most at risk of necrotising enterocolitis?

Preterm infants, especially those with very low birth weight, are most at risk of necrotising enterocolitis. Other risks include formula feeding, perinatal asphyxia, sepsis and a patent ductus arteriosus.

### When is surgery indicated in necrotising enterocolitis?

Surgery is indicated in necrotising enterocolitis for intestinal perforation, pneumoperitoneum and progressive deterioration despite medical treatment. Most babies with Bell stage II disease are managed without an operation.

### Why is human milk recommended to prevent necrotising enterocolitis?

Human milk is recommended to prevent necrotising enterocolitis because it contains protective factors that support gut maturation and a balanced gut flora. Feeds in preterm infants are also advanced slowly to lower the risk.