Methods: Faecal samples were collected at age 1 week, 1 month and 3 months from infants at high risk of allergic disease, who were followed prospectively to age 12 months. Bifidobacteriumspecies were analysed by quantitative PCR and terminal restriction fragment length polymorphism. Infants were examined at 3, 6 and 12 months, and skin prick test performed at 12 months. Eczema was diagnosed according to the UK-Working Party criteria.
Results: The presence of B. catenulatum at 3 months was associated with a higher risk of developing eczema (ORadj = 4.5; 95% CI 1.56 to 13.05, Padj = 0.005). Infants colonised with B. breve at 1 week (ORadj = 0.29; 95% CI 0.09 to 0.95, Padj = 0.041) and 3 months (ORadj = 0.15; 95% CI 0.05 to 0.44, Padj = 0.00001) had a reduced risk of developing eczema. Furthermore, the presence of B. breve at 3 months was associated with a lower risk of atopic sensitisation at 12 months (ORadj = 0.38; 95% CI 0.15 to 0.98, Padj = 0.046). B. brevecolonisation patterns were influenced by maternal allergic status, household pets and number of siblings.
Conclusions: There are temporal variations of Bifidobacterium colonisation patterns early in life and these variations differentially modulate later development of eczema and/or atopic sensitisation in infants at high risk of allergic disease. Modulation of the early microbiota may provide a means for prevention of eczema in high risk infants.