Navigating liver transplantation after malabsorptive bariatric surgery: A new risk of rejection

Abstract

Obesity and its complications, including metabolic dysfunction-associated steatohepatitis, are now major drivers of liver transplantation (LT) worldwide. Therefore, transplant surgeons are increasingly encountering patients who have undergone bariatric surgery prior to LT. Past reports suggested bariatric surgery does not adversely affect LT outcomes such as perioperative complications or survival. However, emerging evidence indicates a nuanced reality. Chang et al recently published a study in World Journal of Transplantation, that LT recipients with previous malabsorptive bariatric surgery (primarily Roux-en-Y gastric bypass) experienced a markedly higher incidence of acute cellular rejection compared to matched controls without bariatric surgery. Potential mechanisms - especially altered pharmacokinetics of immunosuppressants due to surgically modified anatomy - are explored. We consider the need for meticulous therapeutic drug monitoring and tailored immunosuppressive strategies in post-bariatric surgery transplant recipients. While the new data do not suggest changes in one-year survival, the increased early rejection risk signals a need for heightened vigilance. Transplant centers should be aware of this at-risk cohort and may consider proactive measures such as closer drug level monitoring, optimized immunosuppressant formulations, and multidisciplinary care. Ultimately, as bariatric surgery and transplantation continue to intersect, understanding and addressing the unique challenges in these patients will be critical to improving long-term graft outcomes.

Keywords: Metabolic dysfunction-associated steatotic liver disease; Liver fibrosis; Liver transplantation; Bariatric surgery; Acute cellular rejection; Immunosuppression management; Therapeutic drug monitoring

Core Tip: Malabsorptive bariatric surgery (for example, Roux-en-Y gastric bypass and duodenal switch) is increasingly common among liver transplant candidates. Chang et al report significantly higher rates, frequency, and earlier onset of biopsy-proven acute cellular rejection in recipients with prior malabsorptive anatomy, despite comparable perioperative outcomes and one-year survival. This editorial explores plausible mechanisms-especially impaired absorption of oral immunosuppressants-and outlines pragmatic strategies: Intensified therapeutic drug monitoring, dose and formulation adjustments (including extended-release tacrolimus), and multidisciplinary nutrition-pharmacy support to reduce rejection and protect long-term graft function.