45 Decreased Diversity of the Fecal Microbiome in Pediatric Carriage of Clostridium difficile

Abstract

understanding of the relationships between the intestinal microbiota and disease development. By enrolling twin pairs (n=14) in our study, we found a difference in bacterial families of intestinal microbiota composition (0-12 months) existed in dizygotic twins although they lived in the same environment. Among infants from twin (n=14) or singleton (n=7) pregnancy, the initial colonizer was restricted to bacteria from Proteobacteria (Escherichia/Shigella or Sphingopyxis) and Firmicutes (Bacillus or Staphylococcus). During the study period, 52.4% of these subjects developed allergic symptoms, mainly nasal and skin manifestations. Most importantly, we found a distinctive feature of gut microbiota pattern in allergic infants (n= 11) as compared with the healthy babies (n=10). The former harbored relative abundance of Firmicutes bacteria, particularly those from families Clostridiaceae and Lachnospiraceae of Firmicutes. Increasing Clostridiaceae in allergic subjects (72.7%) was observed from 1st to 6th month after birth, and thereafter declined gradually to an undetectable level at 12th month ; whereas the presence of Clostridiaceae in healthy babies was maintained in low frequency from 1st to 12thmonths (p<0.01). On the other hand, rapid growth of Lachnospiraceae bacteria in allergic infants (63.6%) started from 6th month to 12th month, while this pattern was rarely found in healthy control subjects (10%; p<0.01). In addition, reduced colonization of Bifidobacteriaceae was found apparently in allergic subjects, as compared with that of controls (p<0.05). In conclusion, our observation confirmed the link between gut micorbiota patterns and the risk of allergy development. This link may provide some hints for future therapeutic strategies. (Grant Taiwan NSC102-2628-B-002 -027 -MY3 )