Necrotizing Enterocolitis - Cause

Cause

NEC has no definitive known cause. An infectious agent has been suspected, as cluster outbreaks in neonatal intensive care units (NICUs) have been seen, but no common organism has been identified. Pseudomonas aeruginosa is suspected for causing necrotising enterocolitis in premature infants and neutropaenic cancer patients, often secondary to gut colonisation. A combination of intestinal flora, inherent weakness in the neonatal immune system, empirical antibiotic use for 5 days or more, alterations in mesenteric blood flow and milk feeding may be factors. The most common area of the bowel affected by NEC is near the ileocecal valve (the site of transition between the small and large bowel). NEC is almost never seen in infants before oral feedings are initiated. Formula feeding increases the risk of NEC by tenfold compared to infants who are fed breastmilk alone. Expressed breast milk protects the premature infant not only by its antiinfective effect and its immunoglobulin agents but also from its rapid digestion.

A study by the Neonatal Research Network, published in the journal Pediatrics in January 2009, conducted a study regarding the administration of empirical antibiotics in extremely low birth weight infants. The research demonstrated that empirical antibiotic therapy over 5 days for extremely low birth weight babies increased the chance of necrotizing enterecolitis by 4% for each additional day over 5 days.