• Clinical science

Necrotizing enterocolitis (NEC)

Abstract

Necrotizing enterocolitis (NEC) is a dangerous hemorrhagic inflammation of the intestinal wall that most often affects premature infants. Typical symptoms include abdominal distention, 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.

Definition

  • Hemorrhagic necrotizing inflammation of the intestinal wall

Epidemiology

References:[1][2][3]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

  • 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 intestinal immunity
    • Intestinal microbial overgrowth
    • Rapid increase of enteral nutrition

References:[4][5][6][7]

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

References:[8][9]

Diagnostics

Laboratory tests

Imaging

  • Abdominal radiography
    • Pneumatosis intestinalis: Bubbles of gas within the wall of the intestine
    • Portal venous gas (pneumatosis hepatis)
    • Increased intestinal wall thickness
    • Dilated intestinal loops
    • Air‑fluid levels
    • Pneumoperitoneum as a result of intestinal perforation
  • Abdominal ultrasound:
    • Indication: Ultrasound may be helpful for diagnosing NEC when abdominal radiography is inconclusive.
    • Findings
      • Pneumatosis intestinalis
      • Portal venous gas
      • Increased intestinal wall thickness
      • Decreased intestinal wall perfusion

References:[10][11][12][9][13]

Differential diagnoses

NEC Spontaneous intestinal perforation

Intestinal obstruction

Infectious enteritis Allergy to cow's milk
Symptoms
  • Distended abdomen
  • Abdominal pain
  • Vomiting
  • Crepitus
  • Hypotension
  • Abdominal pain
  • Vomiting
  • Bloody stools
  • Rectal bleeding
Other findings
  • X-Ray and ultrasound: pneumatosis intestinalis
  • After the first week and after feeding was begun
  • First week after birth
  • Independent of feeding
  • Failure to pass meconium

  • Positive stool cultures
  • Cow's milk-specific IgE

References:[14][15]

The differential diagnoses listed here are not exhaustive.

Treatment

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

  • Supportive care:
    • Stop enteral feedingparenteral feeding and substitution of fluids
    • Gut decompression via nasogastric tube
    • Correction of metabolic/hematologic abnormalities
    • Stabilization of cardiac and respiratory function
  • IV broad-spectrum antibiotics
  • 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

References:[16][17]

Complications

  • Intestinal perforation:
    • Abdominal radiography: pneumoperitoneum
    • Treatment: surgery
  • Peritonitis
  • Sepsis

References:[17]

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

Prognosis

Mortality rate: approx. 10–30%

References:[18][19]

Prevention

Breast milk has a protective effect

  • 1. Llanos AR, Moss ME, Pinzòn MC, Dye T, Sinkin RA, Kendig JW. Epidemiology of neonatal necrotising enterocolitis: a population-based study. Paediatr Perinat Epidemiol. 2002; 16(4): pp. 342–349. doi: 10.1046/j.1365-3016.2002.00445.x.
  • 2. Yee WH, Soraisham AS, Shah VS et al. Incidence and timing of presentation of necrotizing enterocolitis in preterm infants. Pediatrics. 2012; 129(2): pp. e298–304. doi: 10.1542/peds.2011-2022.
  • 3. Epelman M, Daneman A, Navarro OM et al. Necrotizing enterocolitis: review of state-of-the-art imaging findings with pathologic correlation. Radiographics. 2007; 27(2): pp. 285–305. doi: 10.1148/rg.272055098.
  • 4. Hunter CJ, Upperman JS, Ford HR, Camerini V. Understanding the susceptibility of the premature infant to necrotizing enterocolitis (NEC). http://www.nature.com/pr/journal/v63/n2/full/pr200824a.html. Updated February 1, 2008. Accessed March 7, 2017.
  • 5. Buescher ES. Host defense mechanisms of human milk and their relations to enteric infections and necrotizing enterocolitis. Clin Perinatol. 1994; 21(2): pp. 247–262. pmid: 8070225.
  • 6. Gordon P, Christensen R, Weitkamp J-H, Maheswari A. Mapping the New World of Necrotizing Enterocolitis (NEC): Review and Opinion. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3666872/pdf/nihms435179.pdf. Updated January 1, 2012. Accessed March 7, 2017.
  • 7. Clark DA, Miller MJ. Intraluminal pathogenesis of necrotizing enterocolitis. J Pediatr. 1990; 117(1 Pt 2): pp. S64–67. url: https://www.ncbi.nlm.nih.gov/pubmed?term=2194014.
  • 8. Bell MJ, Ternberg JL, Feigin RD et al. Neonatal necrotizing enterocolitis. Therapeutic decisions based upon clinical staging. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1396409/. Updated January 1, 1978. Accessed March 7, 2017.
  • 9. Neu J. Necrotizing enterocolitis: the search for a unifying pathogenic theory leading to prevention. Pediatr Clin North Am. 1996; 43(2): pp. 409–432. pmid: 8614608.
  • 10. Epelman M, Daneman A, Navarro OM, et al. Necrotizing enterocolitis: review of state-of-the-art imaging findings with pathologic correlation. Radiographics. 2007; 27(2): pp. 285–305. doi: 10.1148/rg.272055098.
  • 11. Christensen RD, Yoder BA, Baer VL, Snow GL, Butler A. Early-Onset Neutropenia in Small-for-Gestational-Age Infants. Pediatrics. 2015; 136(5): pp. e1259–1267. doi: 10.1542/peds.2015-1638.
  • 12. Kenton AB, O'donovan D, Cass DL, et al. Severe thrombocytopenia predicts outcome in neonates with necrotizing enterocolitis. J Perinatol. 2006; 25(1): pp. 14–20. doi: 10.1038/sj.jp.7211180.
  • 13. Shah V, Jones J, et al. Intramural Bowel Gas. https://radiopaedia.org/articles/intramural-bowel-gas. Updated January 1, 2018. Accessed February 15, 2018.
  • 14. Schanler RJ. Clinical features and diagnosis of necrotizing enterocolitis in newborns. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-necrotizing-enterocolitis-in-newborns?source=search_result&search=necrotizing%20enterocolitis&selectedTitle=2~150. Last updated February 18, 2016. Accessed March 7, 2017.
  • 15. Gordon PV, Swanson JR, Attridge JT, Clark R. Emerging trends in acquired neonatal intestinal disease: is it time to abandon Bell's criteria?. J Perinatol. 2007; 27(11): pp. 661–671. doi: 10.1038/sj.jp.7211782.
  • 16. Solomkin JS, Mazuski JE, Bradley JS, et al. Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America. Clin Infect Dis. 2010; 50(2): pp. 133–164. doi: 10.1086/649554.
  • 17. Schanler RJ. Management of Necrotizing Enterocolitis in Newborns. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/management-of-necrotizing-enterocolitis-in-newborns. Last updated May 9, 2017. Accessed February 18, 2018.
  • 18. Horwitz JR, Lally KP, Cheu HW, Vazquez WD, Grosfeld JL, Ziegler MM. Complications after surgical intervention for necrotizing enterocolitis: a multicenter review. J Pediatr Surg. 1995; 30(7): pp. 994–999. pmid: 7472960.
  • 19. Lemelle JL, Schmitt M, de Miscault G, Vert P, Hascoet JM. Neonatal necrotizing enterocolitis: a retrospective and multicentric review of 331 cases. https://www.ncbi.nlm.nih.gov/pubmed?term=8086688. Updated April 1, 1994. Accessed March 7, 2017.
  • Neu J. Necrotizing enterocolitis: the search for a unifying pathogenic theory leading to prevention. Pediatr Clin North Am. 1996; 43(2): pp. 409–432. pmid: 8614608.
last updated 10/19/2018
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