OBJECTIVETo investigate the association between intestinal bifidobacteria and allergic diseases in infants by comparing the composition of intestinal bifidobacteria between healthy infants and infants with allergic diseases.

METHODSA total of 48 infants were enrolled, and fecal samples were collected on days 0, 2, 7, and 15 and at months 1, 6, and 12 after birth. Among these infants, 22 who experienced allergic diseases before the age of 1 year were enrolled as allergic group and 26 healthy infants were enrolled as healthy group. Quantitative real-time PCR was used for the qualitative and quantitative analyses of Bifidobacterium and 8 species of bifidobacteria in fecal samples.

RESULTSThere was a difference in the composition of intestinal bifidobacteria between the two groups within 1 month after birth: the healthy group showed a reduction in bifidobacteria on day 2, while this feature was not observed in the allergic group. Compared with the healthy group, the allergic group had a significantly lower detection count of Bifidobacterium at month 1 (P<0.05) and a significantly lower detection rate of B.breve on day 15 (P<0.05), with delayed colonization of B.infantis.

CONCLUSIONSIntestinal bifidobacteria and their composition within 1 month after birth may be associated with the development of allergic diseases, and this period of time may be a critical period for the prevention and treatment of allergic diseases in infants.