294:
A Comparison Of The Gut Microbiome Of Food Allergic Hosts With and Without Atopic Dermatitis Versus Healthy Controls
Saturday, March 3, 2018: 2:30 PM
S220EF (Convention Center)
Brianne Navetta-Modrov, , ,
RATIONALE: The gut microbiome of peanut allergic children(PAC) with or without Atopic Dermatitis(AD) versus healthy control(HC) subjects has not been well explored.

METHODS: This study is a subgroup analysis of an IRB approved study that compares the microbiome of PAC with and without AD with HC. Bacterial DNA extracted from fecal samples of PAC was assessed. Samples were amplified, sequenced using Nextgen sequencing, and analyzed for bacterial taxonomic classification using V1-9 variable region differences. Sequence data was processed through MiSeq Reporter Metagenomics16S application and the Greengenes 16S ribosomal gene database.

RESULTS: We performed a comparison of 17 PAC(mean age 6 years), 11 with AD and 6 without AD, versus 11 HC(mean age 3.4 years). PAC, regardless of AD status, had an increased proportion of Firmicutes phyla when compared to HC(median=67% vs 47%; Mann Whitney p<0.02). Differences at the class (Alphaproteobacteria p<0.0096, Clostridia p<0.014), order (Clostridiales p<0.014) and family levels (Ruminococcaceae p<0.043) were also observed. The proportion of Firmicutes phyla in PAC with AD versus without AD was not different(median = 69% vs. 63%). Overall, the presence of AD in PAC did not significantly alter the bacterial representation at the phylum, class, order or family levels when compared to HC.

CONCLUSIONS: Recent studies have found the gut microbiome to be altered in AD. In our small cohort of PAC, the noted differences in microbiome compared to HC were not attributed to the presence of AD. Thus, PAC may have an altered microbiome but future studies with larger sample sizes are needed to clarify this relationship.