Incidence and Histologic Features of Transplant Graft Pancreatitis: A Single Center Experience

Pancreas transplant is an effective long-term treatment modality for complicated type 1 diabetes mellitus. However, allograft failure or severe concomitant rejection remain an obstacle to successful transplant outcome, occurring in approximately 21% of recipients within 1 year. Most histologic studies investigating the cause of pancreas transplant failure have concentrated on the presence and severity of acute and chronic cellular or vascular rejection. After vascular thrombosis, graft pancreatitis is the second most frequent complication after transplant.We conducted a retrospective analysis, collecting information from a contemporaneously maintained database of patients after pancreas transplant.We identified 44 patients with rejected allografts from a database of 196 pancreas transplant patients (44/196, 22%). In these identified rejected allografts, 27 patients (61%) had histopathology reports containing 1 or more terms associated with pancreatitis, with the most common histologic finding was being fat necrosis (21/27, 83%), followed by inflammatory or neutrophil infiltrate (13/27, 48%). Sixteen of these patients (60%) had two 2 or more terms histology terms descriptive of pancreatitis records. Ten of the 44 rejected allografts, 10 patients had histologic evidence of vascular or cellular rejection. There was no significant difference in the proportions showing evidence of rejection between groups with (2/27 patients [26%]) and without (3/17 patients [18%]) descriptions of pancreatitis in their medical records (P = .70). When time from transplant to pancreatectomy was analyzed, a larger proportion of pancreatectomies occurred late for patients with descriptions of pancreatitis in their medical records versus patients without (17/26 [65%] vs 4/16 [25%]; P = .05).This case series demonstrates that 61% of rejected allografts over a span of 13 years at a single center had histologic features of graft pancreatitis, suggesting that pancreatitis may be a contributory mechanism to graft failure.