s / Digestive and Liver Disease 46 (2014) e85–e127 e89 style GFD were analysed. A core salivary microbiota of Saharawi T-CD children before and after Italian-style GFDwas identified and compared to Italian T-CD and healthy children (HC). Results: We found significant (P<0.05; FDR<0.05) differences in the salivary microbiota and metabolome between African and Italian-style GFD. Compared to Italian T-CD children, salivary samples of Saharawi T-CD children under African GFD were characterized for the unusual presence of Clostridia and for a high abundance of some other Firmicutes, Actinobacteria and Tenericutes genera. Italian GFD positively affected the abundance of Granulicatella, Porphyromonas and Neisseria. On the contrary, Clostridium, Prevotella and Veillonella strongly decreased after 60 days of Italian GFD. The OTU co-occurrence/exclusion pattern was identified and strong correlations (P<0.05; FDR<0.05) were found between the core bacterial genera and volatile organic compounds (VOC). During Italian GFD, Saharawi T-CD children strongly increased the amount of VOC, especially, acetone and 2-butanone. Conclusions: The insightsgleanedshouldhelp tofindingdietary implementation to improve health status of Saharawi T-CD children, and provide the first strong evidence for the effect of the diet on the human microbiota and metabolome. http://dx.doi.org/10.1016/j.dld.2014.07.063 ORAL ADMINISTRATION OF BUTYRATE PROTECTS AGAINST SENSITIZATION TO COW MILK PROTEIN IN A MURINE MODEL OF COW MILK ALLERGY Margherita Di Costanzo1,∗, Rosita Aitoro1, Lorella Paparo1, Andrew T. Stefka2, Tiffany J. Patton3, Rita Nocerino1, Antonio Calignano4, Rosaria Meli4, Giuseppina Mattace Raso4, Raffaele Simeoli4, Stefano Guandalini3, Cathryn Nagler2, Roberto Berni Canani1 1 Department of Translational Medical Science Pediatric Section, European Laboratory for the Investigation of Food-Induced Diseases, Federico II, Italy 2 Department of Pathology, University of Chicago, IL, USA 3 Department of Pediatric Gastroenterology, University of Chicago, IL, USA 4 Department of Pharmacy, University of Naples,