The multi-omic basis for hepatic encephalopathy recurrence: Analysis of the THEMATIC trial.

Background & Aims: The THEMATIC trial demonstrated that fecal microbiota transplantation (FMT) reduces recurrence of hepatic encephalopathy (HE) in patients already receiving lactulose and rifaximin. The aim of this analysis was to identify multi-omic predictors of HE recurrence among THEMATIC trial participants. Methods: The THEMATIC trial enrolled patients with cirrhosis and HE who received oral or enema FMT Results: HE recurred in 10 of 60 patients (17%), with significantly higher recurrence in the placebo Conclusions: Secondary analysis of the THEMATIC randomized controlled trial indicates that HE recurrence in patients on lactulose and rifaximin is associated with distinct microbiome and metabolomic profiles, particularly involving SCFAs, GABA metabolism, bile acids, and IL-6. Impact and implications: Fecal microbiota transplantation (FMT) reduced hepatic encephalopathy (HE) recurrence in patients receiving lactulose and rifaximin in the THEMATIC trial, but the multi-omic mechanisms underlying this effect were unclear. In this secondary analysis, we found that HE recurrence - regardless of FMT or placebo assignment - was associated with distinct multi-omic signatures, including reduced short-chain fatty acid-producing and increased pathobiont taxa, lower urinary and serum short-chain fatty acids, secondary bile acids, and acetaminophen derivatives, and higher GABA-related and nicotine metabolites, along with elevated IL-6 levels. Notably, patients with greater donor microbiota engraftment had lower rates of HE recurrence. These findings suggest that HE recurrence after FMT reflects a multifactorial process involving alterations in gut metagenomics, systemic metabolomics, inflammation, and donor engraftment. Trial registration: www.clinicaltrials.gov: NCT03796598.