Introduction: Type 1 diabetes auto-antibodies seem to be associated to type 1 diabetes recurrence on the pancreas allograft. The aim of this study was to describe the prevalence of type 1 diabetes auto-antibodies and type 1 diabetes recurrence in a cohort of pancreas allograft recipients.

Methods: Between 2017 and 2019, all pancreas allograft recipients (simultaneous pancreas and kidney, pancreas transplant alone or pancreas after kidney) were screened annually for type 1 diabetes auto-antibodies (anti-IA2, anti-ZnT8 and anti-GAD65). Type 1 diabetes recurrence was defined by the following criteria: hyperglycaemia requiring insulin therapy; a severe loss of C-peptide; seroconversion of type 1 diabetes autoantibodies; the presence of insulitis on pancreas transplant biopsy; and the absence of pancreatic rejection.

Results: 244 patients who received a pancreas allograft before 2017 were included. 108 patients (44%) had anti-GAD65 antibodies, 50 (20%) anti-ZnT8 antibodies et 45 (18%) anti-IA2 antibodies. All three antibodies were positive in 11 patients (5%). Type 1 diabetes recurrence occurred in one patient at 6 years posttransplant and was suspected for seven patients in association to rejection of the pancreas allograft. Between 2017 and 2019, 51 patients received a pancreas allograft. Before transplantation, 23 of those (45%) had anti-GAD65 antibodies, 4 (8%) anti-ZnT8 antibodies and 5 (10%) anti-IA2 antibodies. Only one patient had three positive auto-antibodies. With a follow-up of 0 to 2 years, none of these newly transplanted patients had 3 positive auto-antibodies. No case of recurrence occurred in these patients.

Conclusion: We describe a very high prevalence of type 1 diabetes auto-antibodies after pancreas transplantation, but graft loss due to type 1 diabetes recurrence appears to be a rare event.