Archive for November, 2007

Probiotics Can Prevent Necrotizing Entercolitis

November 1st, 2007 by Dr. Jae H. Kim (MD, PhD, FRCPC, FAAP)

Probiotics are defined as live microbes, such as bacteria, that reside in the gut and provide benefits to the person taking them. Many of us see probiotics in our daily diet such as the “live culture” bacteria found in yogurt. Several recent studies on premature babies have suggested that giving probiotics can significantly reduce the incidence of NEC (1, 2).

Interestingly, our body is composed of more bacteria cells than human cells and depends on beneficial bacteria to maintain normal health. At birth, the large bowel of term babies is quickly filled with bacteria from their mother’s colon that are normally living in the birth canal. These beneficial bacteria happily grow there and help to provide extra nutrients and boost the immune system of the individual.

Premature babies have a poorly developed bacterial colony in their large bowel. Many premature babies miss out on the early loading of beneficial bacteria by getting delivered through Cesarean section. Instead, some of these infants inherit many of the nastier bacteria found in the neonatal intensive care unit where we also inadvertently make things worse by treating babies with broad coverage antibiotics which eliminate both
harmful and beneficial bacteria. We find that the number and diversity of bacteria in their bowel do not develop to the same degree as in normal term babies.

These factors have been suggested as some of the possible reasons why premature babies develop NEC. Doctors are now finding that feeding back high amounts of “good” bacteria, ones that are normally present in the colon, on a daily basis may help temporarily promote the growth of “good” bacteria in the large bowels of vulnerable premature babies. Summarized results from
several studies support there being a strong benefit to using probiotics for premature babies to prevent NEC or reduce the severity of NEC. Infants who received probiotics had 1/3 the number of cases of NEC than those who did not. Just as important, those who receive probiotics had less severe NEC
and less death due to NEC than controls. Still, the exact effects of how probiotics work are not well understood.  Some possible effects include reduced “leakiness” of the bowel, increased immune defenses and reduced inflammation.

Summary

The use of probiotics or live beneficial microbes for premature babies is very promising in reducing the number of babies who develop necrotizing enterocolitis. Currently many questions still remain as to the best type of probiotics to use, the dosage to give, and the time and duration of the treatment. Ideally, a large multicenter study involving a couple thousand premature infants will be required for this treatment to be more broadly accepted in North America.

1. Deshpande G, Rao S, Patole S. Probiotics for prevention of
necrotising enterocolitis in preterm neonates with very low birthweight: a systematic review of randomised controlled trials. Lancet 2007;369(9573):1614-20.

2. Barclay AR, Stenson B, Simpson JH, Weaver LT, Wilson DC.
Probiotics for Necrotizing Enterocolitis: A Systematic Review. J Pediatr Gastroenterol Nutr 2007;45(5):569-576.