SAN DIEGO – A retrospective study provides insight as to why some patients have a milder versus a more severe course of inflammatory bowel disease (IBD) after liver transplant for primary sclerosing cholangitis (PSC).
Recurrent PSC, prolonged use of steroids, and cancer development after liver transplant were associated with a milder course of IBD, but tacrolimus use was associated with increased IBD flare post transplant.
“The course of IBD is highly variable after liver transplant for PSC. PSC is associated with IBD in 60% to 90% of patients, and IBD worsens in about 30% of PSC-IBD patients after transplant. We wanted to explore the risk factors for worsening IBD in this setting,” Dr. Mohamad Mouchli of the Mayo Clinic in Rochester, Minn., explained at the annual Digestive Disease Week.
For purposes of this study, progression of IBD was defined as the need for escalation of medical therapy, compared with before liver transplant, or need for colectomy for medically refractory IBD.
The study population included patients with PSC-IBD who underwent liver transplant for noncholangiocarcinoma indications at the Mayo Clinic from 1998 to 2012. Patients were followed through February 2015.
The investigators screened 373 patients: After exclusions for cancer, no IBD at transplant, and pretransplant colectomy, 151 patients with an intact colon were left and formed the basis of further analysis.
Median age at transplant was 46 years and two-thirds of the patients were male. Transplant-related variables included the following: 23% experienced allograft failure, 36% had recurrent PSC, 25.2% had CMV infection, 19.2% were retransplanted, 22.5% developed cancer after liver transplant, and 52.3% had acute cellular rejection.
Before transplant, 69 patients had quiescent IBD with no therapy and 62 were maintained on 5-aminosalicylates. Post transplant, despite transplant-related immunosuppression, 56 patients (37.1%) required escalation of therapy, 87 patients (57.6%) had a stable course, and 8 patients (5.3%) improved.
Risk of IBD progression at 1, 5, and 10 years was 4%, 18.5%, and 25.5%, respectively. Thirty-five patients underwent colectomy after transplant: the 1-, 5-, and 10-year risks of colectomy were 2%, 9.3%, and 17.2%, respectively. Fourteen percent of patients required anti–tumor necrosis factor therapy after transplant.
On multivariate analysis, tacrolimus exposure emerged as a risk factor for progression of IBD. Tacrolimus immunosuppression was twice as likely as cyclosporine-based immunosuppression to lead to IBD progression. By contrast, recurrent PSC, use of steroids for longer than 6 months, and cancer development after liver transplant were protective of IBD progression.
No association was found between progression of IBD and transplant-related infection or mismatch, immunosuppression with mycophenolate or azathioprine, or IBD-related factors such as pretransplant IBD status or empirical initiation of 5-aminosalicylates within 4 months of liver transplant. During the question-and-answer session following his presentation, Dr. Mouchli was asked whether these results justify prophylactic colectomy. He said that could be considered in patients with active IBD before transplant, but on a case-by-case basis.