We searched the Cochrane Library (1980 to present) and MEDLINE (1980 to present) using the search terms “necrotizing enterocolitis” or “NEC”. We selected articles published in English, focusing on publications from the past 5 years, but including older publications that are commonly referenced or highly regarded. We also searched the reference lists of articles identified by this search strategy and selected additional publications that we judged relevant. Several reviews and book
SeminarNecrotising enterocolitis
Introduction
Necrotising enterocolitis is one of the most common gastrointestinal emergencies in newborn infants. First described over a century ago, this disease remains an enigma. Pathogenesis is still unproven; treatment is difficult and often proves inadequate; and no effective prevention strategy has been agreed. The disease is especially poignant because it mainly affects premature infants who have survived the early neonatal period and subsequently face a disease with high morbidity and mortality. We also note that spontaneous intestinal perforation has become an increasingly common gastrointestinal emergency in preterm infants. Although the emergence of this disorder is of concern, it probably represents a separate disease entity that is beyond the scope of this Seminar.
Section snippets
Epidemiology
Although multiple case-control studies have attempted to identify demographic or clinical risk factors (or both) for the development of necrotising enterocolitis, prematurity and low birthweight are the most consistently recorded risk factors. Over 90% of infants who develop the disease are born preterm, and the risk is inversely related to birthweight and gestational age.1, 2, 3, 4, 5 Advances in obstetric and neonatal care have improved survival rates for smaller, more immature infants, and
Pathophysiology
The pathophysiology of necrotising enterocolitis remains poorly understood. Premature infants are at high risk because of developmental immaturity of key functions, in particular gastrointestinal motility, digestive ability, circulatory regulation, intestinal barrier function, and immune defence. Other potential contributing factors include hypoxic-ischaemic injury, feeding with formula milk, and colonisation by pathological bacteria (figure 1).1, 40
Clinical presentation
Necrotising enterocolitis presents with both gastrointestinal and systemic signs.13, 133 Age at presentation is inversely related to gestational age at birth,2, 134 with full-term infants often presenting in the first few days of life.29, 135 Neonates most commonly present with feeding intolerance, delayed gastric emptying, abdominal distention or tenderness (or both), occult or gross blood in the stool, lethargy, apnoea, respiratory distress, or poor perfusion. Because early signs of this
Diagnosis and management
When necrotising enterocolitis is clinically suspected, radiological and laboratory studies should be obtained to confirm the diagnosis and to aid in management (figure 6). Clinicians examine serial abdominal films (supine anterioposterior view) for signs of the disease. A horizontal view can reveal free air (supine cross-table lateral or a left-side down decubitus). Early non-specific signs include diffuse distention and asymmetric bowel gas pattern. Definite signs include pneumatosis
Prevention
Strategies to prevent necrotising enterocolitis should improve both short-term and long-term outcomes for VLBW preterm infants (panel 2). Feeding of human milk and conservative feeding practices, especially in infants suspected to be at higher risk, can reduce the incidence of the disease.6, 7, 150 However, researchers do not agree on whether human milk from a donor is as protective as mother's milk.8, 151 Antenatal steroids,110 IgA supplementation,152, 153 arginine supplementation,154
Search strategy and selection criteria
References (181)
Epidemiology of necrotizing enterocolitis
Clin Perinatol
(1994)- et al.
Breast milk and neonatal necrotising enterocolitis
Lancet
(1990) - et al.
The NICHD neonatal research network: changes in practice and outcomes during the first 15 years
Semin Perinatol
(2003) - et al.
Portal venous gas and surgical outcome of neonatal necrotizing enterocolitis
J Pediatr Surg
(2005) - et al.
Surgical therapy for necrotizing enterocolitis: bringing evidence to the bedside
Semin Pediatr Surg
(2005) - et al.
Complications after surgical intervention for necrotizing enterocolitis: a multicenter review
J Pediatr Surg
(1995) - et al.
Operative strategies for necrotizing enterocolitis: The prevention and treatment of short-bowel syndrome
Semin Pediatr Surg
(2005) - et al.
Necrotizing enterocolitis in full-term infants
J Pediatr Surg
(2003) - et al.
Ontogeny of fetal rabbit upper gastrointestinal motility
J Surg Res
(2001) - et al.
Gastric emptying cycles in the human fetus
Am J Obstet Gynecol
(2005)