Recent developments in necrotizing enterocolitis (NEC) have focused on the potential role of new biomarkers and preventive strategies (JPEN 2012; 36: 30S-35S).  In this report, the clinical/diagnostic features of NEC are reviewed:

• classic form develops between 29-32 weeks corrected gestational age
• features include feeding intolerance, abdominal distention, bloody stools
• imaging features: pneumotosis intestinalis, portal venous gas, paucity of gas, fixed bowel loops
• full term or late NEC usually occurs in the setting of risk factors like congenital heart disease, exchange transfusions, gastroschisis, and neural tube defects
• spontaneous intestinal perforation due to glucocorticoids or indomethacin may be confused with NEC.  It usually occurs earlier than NEC

This review describes the potential for new biomarkers, including urinary I-FABP & fecal calprotectin. These assays would need to be available with very short turn-around time given the often rapid development of NEC.

Finally, this articles discusses the evidence for preventive measures.  Human milk has been shown to decrease NEC and gradual introduction of feedings remains important. With regard to microbial colonization, NEC does not occur until at least 8-10 days postpartum coincident with anerobic bacterial colonization of intestinal tract.

This has led to attempts to alter the colonization to decrease NEC incidence. 16 randomized controlled trials with 14 different probiotics have been completed.  Most are underpowered.  “The available trials do not permit a decision to be made with respect to optimum strain, dosing, or protocol.”  In a cautionary note, a preterm pig model demonstrated an increase NEC incidence with the use of a specific probiotic (Pediatr Res 2011; 69: 10-16).  Furthermore, probiotics are plagued by a lack of adequate quality control.

Additional references:

• -Ann Surg 2010; 251: 1174-80.  Non-invasive biomarkers for NEC.
• -J Peds 2011; 158: 672-74.  Caution advised with probiotics for NEC.
• -J Peds 2011; 159: 392. n=124 cases (248 controls). retrospective study suggested that abx exposure is a risk factor for NEC (3-fold risk).  Abx -marker for illness or true predisposing factor?
• -NEJM 2011; 364: 255-64.  NEC review.
• -Cochrane Database Syst Rev 2011; 3: CD005496.  Probiotics for NEC.
• -NEJM 2011; 364: 1877. Probiotics likely helpful in preemies with birth wt >1000gm.
• -NEJM 2010; 364: 255.
• -Pediatrics 2010; 125: 921-30.  Meta-analysis of probiotics for NEC.
• -JPS 2009; 44: 1072-76. Mortalitiy of NEC expressed by birth weight.
• –Pediatrics 2008; 122: 693-700. Multicenter trial of probiotics in VLBW for NEC prevention.
• -J Pediatr 2008; 153: 339. Cluster of NEC due to norovirus.
• -Pediatrics 2007; 119; e164. Rate of 0.4% among large cohort of infants w/o indocin, steroids & w slow delayed feedings.
• -Pediatrics 2006; 117: e137. H2-blockers associated with increased NEC (?causal)
• -Pediatrics 2005; 116: 1064. CRP helpful. If CRP was persistently normal, antibiotics were aborted and enteral feeds restarted safely.
• -Pediatrics 2005; 115: 1-4 & 171 editorial.  Probiotics decreased NEC in this study.
• -J Pediatr 2003; 143: 543. Images of pneumotosis.