Sa1917 – A Microbial Signature Predicts Advanced Fibrosis in Human Liver Disease

Background:The presence of advanced fibrosis is an important predictor of the severity of chronic liver disease.The aims of the study were to i) establish the microbial profiles differentiating varying levels of fibrosis as well as varying etiologies of liver disease and to ii) create a predictive model for liver fibrosis based upon microbial profiles.Methods: Stool samples were obtained from patients with chronic liver disease undergoing Fibroscan® (ultrasound elastography) at the Greater Los Angeles VA from 6/2017 to 6/2018.Healthy control patients were also recruited as a reference population.Patients were excluded if they had only acute liver injury, treated hepatitis C infection with SVR12, antibiotic treatment within 3 months of stool collection, a special diet (e.g.vegan, vegetarian, high protein, gluten free), history of inflammatory bowel disease, history of irritable bowel syndrome, history of GI surgeries, or probiotic use.Sequencing of the V4 region of 16S ribosomal RNA was performed and processed using DADA2 package in R. Microbiome data was analyzed for alpha diversity, beta diversity, and association of taxa abundance with clinical parameters.Association of microbial genera with advanced fibrosis (F3/F4 fibrosis) and clinical features were evaluated with DESeq2 in R. Using differentially abundant microbes found in patients with advanced fibrosis vs. mild/moderate fibrosis (