618. Do Clinical Factors Affect Microbial Engraftment After Fecal Microbiota Transplantation in Recurrent Clostridium difficile Infection?

Abstract

BackgroundFecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridium difficile infection (rCDI). Few studies have evaluated clinical factors associated with microbial engraftment. We describe microbial changes post-FMT and clinical factors impacting engraftment.MethodsPatients undergoing FMT for rCDI via colonoscopy were enrolled. Clinical data and stool were collected pre- and 8 weeks post-FMT. Microbial profiles were assessed by 16S rRNA sequencing. Difference in microbial alpha and β-diversity between groups was determined. Significance testing was assessed using Mann–Whitney–Wilcoxon and PERMANOVA tests. The Jensen Shannon divergence (JSD) between donor and their recipient post-FMT was used as a measure of engraftment. The association of clinical factors on engraftment was evaluated by linear regression.ResultsA total of 12 patients received an FMT from 12 unique donors. The efficacy rate was 92%. Mean recipient age was 60 years (range: 33–87) with more females (7/12).Recipients pre-FMT alpha diversity was significantly lower compare to donors (P = 0.04, Figure 1a). This difference dissipated post-FMT (P = 0.67). On β-diversity analysis, the recipients pre-FMT samples clustered separately from their post-FMT samples (P = 0.01, Figure 1b), with the post-FMT samples shifting closer to the donor samples. Proteobacteria was dominant in patients’ pre-FMT samples and were substantially reduced post-FMT, combined with an expansion in Bacteroidetes (Figure 2).On linear regression analysis, clinical factors (age, sex, previous recurrent CDI episodes, inflammatory bowel disease, proton pump inhibitor, immunosuppression, previous anti-CDI antibiotic courses, probiotics) were not significantly associated with engraftment outcomes.ConclusionThere is a significant and durable shift in recipients’ microbial profile to resemble their donor post-FMT. Recipients’ pre-FMT clinical factors did not significantly affect microbial engraftment. Future metagenomic studies may help elucidate whether clinical factors impact engraftment.Figure 1: (A) Alpha diversity. (B) Bray–Curtis principle component plot.Figure 2: Relative abundance of taxa at Phylum level.Disclosures All authors: No reported disclosures.