The team at the University of Turku, Finland, analysed the gut flora of 13 babies with eczema. Stool samples were taken from all the babies before weaning and analysed for levels of "unfriendly" gut organisms, particularly Escherichia coli and other human gut pathogens.

Previous work has shown that high levels of these bacteria can stimulate the immune system to boost production of IgE antibodies, which are involved in causing allergic reactions.

The babies were weaned onto hydrolysed whey formula feed. Seven were also given supplements of Bifidobacterium lactis - a common benign bacterium found in the gut of healthy people. After four months, the infants' gut bacteria and IgE concentrations were analysed.

The babies receiving the probiotic supplements had significantly reduced levels of E. coli and bacteriodes in their stool samples - and significantly lower levels of IgE antibodies.

Simon Murch, a paediatric gastroenterologist at the Royal Free Hospital in London says the results are "interesting", but not unexpected. But, he says, the findings conflict with other research on allergy and gut bacteria.

One unpublished 20-year follow-up study in Prague has shown that E. coli given to babies at birth reduces allergy later in life. "Two E. coli formulae are commercially available in Czechoslovakia and are frequently given to infants there," Murch told New Scientist.

Journal reference: Gut (vol 51, p 51)

Gaia Vince

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