What is necrotizing enterocolitis (NEC)?

Necrotizing enterocolitis (NEC) is an inflammation in the intestines (usually the colon) that can be life-threatening if not treated right away. NEC may affect only the lining of the intestine or its entire thickness. The damage caused by NEC to the intestinal tissues can cause a hole in the intestines that allows the bacteria normally present only in the intestinal tract to leak out into the abdomen and cause infection. Once this occurs, the infection can progress very quickly and is considered a medical emergency.

NEC most commonly affects premature babies, accounting for 60 to 80% of cases. It is the most common gastrointestinal emergency in the Neonatal Intensive Care Unit (NICU). It usually occurs within 3-12 days after birth.

What causes necrotizing enterocolitis (NEC)?

The cause of NEC is unclear; it may be a result of too little oxygen or blood flow reaching the intestines, causing them to weaken. Once in this weakened state, bacteria from food that enters the intestines can cause damage or death to the tissues and lead to a severe infection. Contrary to popular belief, breast milk does not cause or prevent NEC. Prematurity is the most common cause.

What are the symptoms of necrotizing enterocolitis (NEC)?

Symptoms of NEC usually develop in the first 2 weeks and may include the following:

  • Bloating or swelling in the tummy
  • Poor tolerance to feedings
  • Frequent vomiting (possibly green in color)
  • Bloody stool (bowel movements)
  • Redness or abnormal color to the tummy
  • Lethargy (lack of energy)
  • Fever
  • Apnea (pauses in breathing)