Post-transplant acute pancreatitis after pancreas transplantation: application of the International Study Group for Pancreatic Surgery definition and clinical impact in a multicenter cohort study.

Graft pancreatitis is a clinically relevant but poorly standardized complication after pancreas transplantation (PT). In contrast, post-pancreatectomy acute pancreatitis has been formally defined and validated by the International Study Group for Pancreatic Surgery (ISGPS). This study assessed the clinical applicability of an adapted ISGPS-based framework to define post-transplant acute pancreatitis (PTAP) after PT and its association with clinically relevant outcomes. Consecutive patients undergoing PT at three European centers between 2010 and 2024 were included. PTAP was defined by sustained postoperative hyperamylasemia (POH) for ≥48 h combined with CT findings consistent with pancreatitis within 30 days after transplantation. Imaging was performed in 89% of patients based on clinical indication and center-specific protocols. Among 432 patients, the adapted definition was applicable in 416. Sustained POH occurred in 196 patients (47%), and PTAP was diagnosed in 86 (21%). PTAP was the only independent predictor of severe postoperative complications (OR, 2.482; P = 0.001), was independently associated with prolonged hospital stay (OR, 3.817; P < 0.001), and with worse death-censored graft survival (P < 0.001). Cold ischemia time was the only independent determinant of PTAP (P < 0.001). PTAP was a frequent and clinically meaningful complication after PT, occurring in approximately one in five patients and associated with worse short- and long-term outcomes.