Necrotizing Enterocolitis

Snapshot

• A 26-day-old boy presents to the pediatrician due to increased irritability and episodes of vomiting after feeding. He also reports that the patient appears lethargic. Obstetric history is significant for a spontaneous vaginal delivery at 29 weeks gestation and weight of 1005 grams at birth. He was born to a 32-year-old mother. On physical examination, there is abdominal distension. Laboratory testing is significant for heme-positive stool and thrombocytopenia. An abdominal radiograph is shown.

Introduction

• Clinical definition
  • acute neonatal intestinal necrosis
• Epidemiology
  • incidence
    • 0.1% of all live births
  • demographics
    • more common in males
  • risk factors
    • infants born ≤ 35 weeks gestation especially with
      • a birth weight < 1000 g
    • early-onset neonatal sepsis
    • mechanical ventilation
    • 5-minute APGAR < 7
• Pathogenesis
  • although the pathogenesis is unclear, it is believed to be due to an exaggerated inflammatory response to some sort of insult (e.g., enteral feeds in a premature infant) that injures
    • immature intestinal epithelial cells
• Associated conditions
  • prematurity
• Prognosis
  • 15-30% overall mortality and increased mortality with
    • prematurity
• low birth weight

Presentation

• Symptoms
  • feeding intolerance (e.g., emesis)
  • lethargy
  • apnea
  • dyspnea
    • may require ventilatory support
• Physical exam
  • abdominal distension
• blood in stool

Imaging

• Radiography
  • view
    • abdominal in the supine position
  • indication
    • abdominal radiagraphy is used to confirm the diagnosis of suspected necrotizing enterocolitis
  • findings
    • findings suggestive of necrotizing enterocolitis include
      • pneumatosis intestinalis (hallmark of the disease) 
      • hepatobiliary gas
• pneumoperitoneum

Studies

• Labs
  • complete blood count (CBC)
    • thrombocytopenia is often found and can suggest
      • worsening disease progression if they are declining
  • serum chemistry
  • blood culture
• Diagnostic criteria
  • the diagnosis is based on abdominal radiographic findings (e.g., pneumatosis intestinalis) and characteristic clinical findings such as
    • abdominal distention
• rectal bleeding (the bleeding can be occult or grossly present)

Differential

• Spontaneous intestinal perforation
• Infectious enteritis

Treatment

• Medical
  • intravenous broad-spectrum antibiotics
    • indication
      • administered after appropriate samples are obtained for culture
    • modalities
      • an example of medications used for necrotizing include
        • ampicillin, gentamicin, and metronidazole
• Operative
  • abdominal surgery
    • indication
      • an absolute indication for abdominal surgey is intestinal perforation
    • technique
      • exploratory laparotomy with bowel resection
• primary peritoneal drainage

Complications

• Bowel perforation
• Disseminated intravascular coagulation
• Infectious complications (e.g., peritonitis)