The Effectiveness of Oral Vancomycin on Inflammatory Bowel Disease in Patients With Primary Sclerosing Cholangitis: A Systematic Review.

Background: Approximately 70% of primary sclerosing cholangitis (PSC) patients have inflammatory bowel disease (IBD). The IBD therapies currently used to treat PSC-IBD patients have side effects and can be costly. Oral vancomycin (OV)-a safe, economical, and convenient therapy-has been reported to be a salvage therapy in refractory PSC-IBD patients. This systematic review aims to summarize the current literature regarding the effectiveness and safety of OV to treat IBD in PSC patients.

Methods: A systematic literature review of Scopus, Embase, Web of Science, MEDLINE, and CINAHL was performed until March 2024. The Murad scale, Newcastle-Ottawa scale, and Cochrane Collaboration Risk of Bias Tool were used to determine the quality of the case reports and case series, cohort studies, and randomized controlled trial (RCT), respectively. The outcomes sought were response or remission across clinical, biochemical, endoscopic, and histological parameters.

Results: Of the 1725 published studies, we identified 9 case reports, 7 case series, 3 cohort studies, and 1 RCT. Most studies reported an improvement in clinical IBD symptoms such as diarrhea and hematochezia. Fewer publications provided supporting objective data in the form of fecal calprotectin, endoscopic Mayo scores, and histology. There were no reports of vancomycin-resistant enterococci infections.

Conclusions: Oral vancomycin appears safe and effective to treat IBD in a subset of PSC patients. Future studies would benefit from prospective data collection incorporating standardized symptomatic, endoscopic, and histologic indices. Ultimately, a well-powered RCT is needed to better assess the effectiveness, safety, and durability of OV therapy.