We intend to enroll 18 patients with cirrhosis who do not have hepatic encephalopathy to prospectively evaluate the impact of rifaximin on B-cell phenotype and function. We plan to employ a randomized, double-masked, prospective crossover design to minimize bias. Subjects will be randomized to receive either rifaximin SSD 80mg or a matched placebo once daily for 12 weeks then crossed over to opposite therapy for 12 weeks. Serum and lymphocytes will be collected at baseline and every 4 weeks for in vitro assessment markers of gut microbial translocation and B-cell assays. Stool will be collected at baseline and every 12 weeks for future evaluation of changes of the gut microbiome.
