Effect of Orthotopic Liver Transplantation on Patients With Primary Sclerosing Cholangitis and Ileal Pouch-Anal Anastomosis: A Systematic Review and Meta-Analysis

Background: Pouchitis is the most common complication in patients undergoing Ileal pouch-anal anastomosis (IPAA), which can develop in its acute form in up to 66% of patients. Patients with primary sclerosing cholangitis (PSC) are at an increased risk for developing pouchitis, which occurs in 60%-90% of non-transplanted patients with PSC/IBD. There is limited data on the effect of orthoptic liver transplantation (OLT) on the risk of developing pouchitis. We aimed to objectively assess whether OLT significantly modifies the risk of developing pouchitis in patients with PSC/IBD. Methods: PubMed, Scopus, Embase, Cochrane, and ScienceDirect databases were searched through September 2023 for studies that describe the outcomes of IPAA in patients with PSC/IBD with a history of OLT. Pooled proportions, odds ratio (OR), and 95% confidence intervals (CIs) for data were calculated utilizing a random effects model. Using the Freeman-Turkey double arcsine transformation (FTT) method, the pooled weight-adjusted estimate of event rates for clinical outcomes in each group was also calculated. Heterogeneity between studies was assessed using the Cochrane Q statistic (I2). Results: Seven studies with a total of 291 patients with a history of PSC/IBD and OLT were identified. The pooled overall risk of pouchitis in PSC/IBD patients with a history of OLT was 65% (95% CI:0.57-0.72), with no heterogeneity observed in the analysis (I2 =0%). In a subgroup analysis of patients who had IPAA-then-OLT, 3 studies with 28 patients were included; the pooled risk of pouchitis was 83% (95% CI: 0.71-0.94; I2=0%) which was significantly higher (P < 0.001) than the OLT-then-IPAA group (59%; 95 CI: 0.48-0.71; I2=0%). There was no difference in the risk of pouchitis between OLT and non-OLT groups (OR=1.36; 95% CI: 0.37-5.0). Conclusions: Our meta-analysis showed that pouchitis occurs frequently in patients with OLT for PSC, especially in patients with IPAA before the OLT. However, further studies with larger sample sizes are warranted to determine the burden of OLT on rates of pouchitis in the UC/PSC patient population. Furthermore, close coordination between transplant hepatologists and IBD specialists is required.