A278 ESCHERICHIA ABUNDANCE AND LOW FECAL BUTYRATE IN CHILDREN WITH INTESTINAL FAILURE

Short bowel syndrome (SBS) is the leading cause of intestinal failure (IF) in children. The goal for a child with IF is to undergo sufficient intestinal adaptation to achieve enteral autonomy and thus be able to discontinue parenteral nutrition (PN). The prognosis for each child may be different depending on anatomic differences such as small intestinal length, the number of surgeries, the gestational age, and the underlying etiology. The composition of the fecal microbiome may represent an additional independent risk factor for dependence on PN. We sought to compare the intestinal microbiome of children with SBS who continue to require PN (defined as SBS+IF), to those with SBS who have discontinued PN, using high-throughput sequencing to further understand host-microbe interactions in these populations. Furthermore, we sought to quantify the short chain fatty acid (SCFA) production between groups as well as total fecal bacterial load. A total of 53 stool samples were collected over 6–15 months. Six children with SBS+IF submitted 34 samples and 6 children with SBS who discontinued PN submitted 15 samples; these were compared to samples from 5 control children. Fecal samples were analyzed by 16S rRNA gene sequencing using the MiSeq Illumina sequencer. SCFA levels, including butyric acid, were measured in stool samples by mass spectrometry. Bacterial load was measured by qPCR. Children with SBS+IF demonstrated the most significant dysbiosis with the lowest Shannon diversity and an abundance of the Escherichia genus seemingly attributed to the pro-inflammatory species E. coli. There was a significant 168-fold increase in the abundance of Escherichia compared to control children. Commensal anaerobes known to produce SCFA including Ruminococcaceae and Lachnospiraceae were significantly reduced in those with SBS. Similarly, measured butyric acid was significantly reduced in children with IF (median 0.37 nmol/mg; p<0.0001). Children with IF had a significantly reduced bacterial load in stool samples compared to controls (median 124.2 nmol/L vs. 1225 nmol/L; p=0.006). Significant dysbiosis characterized by a reduction in diversity and over-population of Escherichia as well as a significant reduction in the critical SCFA, butyric acid, were identified in children with IF. These findings have potential implications for intestinal epithelium barrier function, intestinal permeability and host-microbe immune response in this patient population. CAGRegional Medical Associates of Hamilton