Changes in human microbiota have been suggested as a risk factor for atopic diseases. In the current study, the association between neonatal fecal flora and the development of atopic disorders was investigated. The intestinal microbiota were examined in infants in a birth cohort of 411 high-risk children followed for six years by clinical assessments at 6-month intervals, as well as at acute symptom exacerbations. Bacterial flora was analyzed at 1 and 12 months of age and outcome measures included the development of allergic sensitization (skin test and specific serum IgE), allergic rhinitis, peripheral blood eosinophil counts, asthma, and atopic dermatitis. Results revealed that bacterial diversity in the early intestinal flora 1 and 12 months after birth was inversely associated with the risk of allergic sensitization (serum specific IgE P = .003; skin prick test P = .017), peripheral blood eosinophils (P = .034), and allergic rhinitis (P = .007). The authors concluded that reduced bacterial diversity of the infant’s intestinal flora was associated with increased risk of allergic sensitization, allergic rhinitis, and peripheral blood eosinophilia, but not asthma or atopic dermatitis, in the first six years of life. J Allergy Clin Immunol. 2011 Jul 20. PMID: 21782228.
