• Clinical science

Necrotizing enterocolitis


Necrotizing enterocolitis (NEC) is a dangerous hemorrhagic inflammation of the intestinal wall that most often affects premature infants. Typical symptoms include abdominal distension, gastric retention, tenderness, rectal bleeding, and visible intestinal loops lacking peristalsis. A radiographic finding of gas within the wall of the intestine (pneumatosis intestinalis) confirms the suspected diagnosis. Conservative management of the condition involves parenteral nutrition and antibiotics. In the case of advanced NEC and intestinal perforation, however, surgery is necessary.




Epidemiological data refers to the US, unless otherwise specified.


  • The causes of necrotizing enterocolitis are not fully understood but multiple factors contribute to the development of the condition.
    • Intestinal wall perfusion and motility disorders
    • Defective or underdeveloped immune system
    • Intestinal microbial overgrowth
    • Formula feeding
    • Rapid increase of enteral nutrition


Clinical features

Bell staging criteria
Stage Diagnosis Symptoms
Stage I
  • Suspected NEC
  • Lethargy, distended and shiny abdomen, gastric retention, vomiting, diarrhea, rectal bleeding
Stage II
  • Proven NEC
  • Stage I symptoms + abdominal tenderness, visible intestinal loops lacking peristalsis
Stage III
  • Advanced NEC



Laboratory tests



Differential diagnoses

Differential diagnoses of necrotizing enterocolitis
Features NEC Spontaneous intestinal perforation

Intestinal obstruction

Infectious enteritis Allergy to cow's milk
  • Distended abdomen
  • Hypotension
  • Abdominal pain
  • Vomiting
  • Bloody stools
  • Rectal bleeding
Other findings
  • First week after birth
  • Independent of feeding
  • Cow's milk-specific IgE


The differential diagnoses listed here are not exhaustive.


Treatment should be initiated promptly when NEC is suspected to prevent complications such as perforation, peritonitis, and sepsis.

  • Supportive care:
    • Stop enteral feeding → parenteral feeding and substitution of fluids
    • Gut decompression via nasogastric tube
  • IV broad-spectrum antibiotics: e.g., ampicillin, gentamicin, and metronidazole for anaerobic coverage
  • Radiographic monitoring: plain supine abdominal radiographs every 6–12 hours in the initial phase of the disease
  • Surgery: primary peritoneal drainage and/or laparotomy with necrotic bowel excision
    • Indications: perforation, peritonitis and/or clinical worsening despite medical therapy




We list the most important complications. The selection is not exhaustive.


Mortality rate: approx. 10–30%



Breast milk has a protective effect

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last updated 10/23/2020
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