Probiotics ("good bacteria") may reduce the risk of necrotising enterocolitis in preterm neonates (premature babies) born before 33 weeks gestation, says an Article in this week's special gastroenterology edition of The Lancet.

Necrotising enterocolitis is an infection which attacks and kills the lining of the bowel and affects mainly premature infants.

Dr Sanjay Patole, King Edward Memorial Hospital for Women, Perth, Western Australia, Australia, and colleagues studied the results of seven trials involving babies born at 33 weeks or earlier and less than 1•5 kg in body weight.

In a meta-analysis (a study which combines the results of previous trials) the researchers found the risk of contacting necrotising enterocolitis was reduced by 64% and the risk of death reduced by 53% in groups of premature babies given probiotics compared to the control groups. The risk of sepsis occurring in babies was not significantly different between the groups given probiotics and the control groups.

And the time taken for the premature babies to achieve full feeds was less when they were given probiotic supplements, by an average of nearly three days.

The authors say: "The remarkably consistent results, despite the distinct differences in dose, timing, and types of organism used, suggest that substantial latitude might be available in the choice of an effective probiotic regimen in the design of further trials."

They conclude: "If a large, well designed-trial confirms our results, it could make a very strong case for the routine use of probiotics in preterm neonates."

In an accompanying Comment, Dr Carlo Caffarelli, Paediatric Clinic, University of Parma, Italy, said: "The usual measures for the prevention of necrotising enterocolitis are feeding with human milk and delaying preterm delivery. The overview by Patole and colleagues is an important step towards an evidence-based use of probiotics.

"However, further large trials are needed before recommending these promising agents."

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