Allogeneic islet transplantation for diabetic patient post-kidney transplant diabetes in 4 cases

Objective: To evaluate the efficacy and safety of allogeneic islet transplantation for treating post-kidney transplant diabetes.
Case Data: Three cases of allogeneic islet transplantation for post-kidney transplant diabetes performed at our center between May and October 2024 were reviewed. All donors were brain death due to 2 of traumatic brain injury and 2 of cerebral hemorrhage, with an average age was 45 (44, 55, 33, 49) years and an average BMI of 24.1 (24.2, 25, 23.8, 24.2), normal blood glucose, and HbA1c levels between 5.0-6.0%. Recipients had type 2 diabetes for an average of 2.8 years (5 years, 2 years, 1 year 9 months, 2.5years) post-kidney transplantation, with good histocompatibility. Pancreata were processed in a GMP-compliant laboratory, yielding 292,500 IEQ (270,000, 320,000, 300,000，20,0000). Islets were infused via percutaneous transhepatic portal vein puncture under DSA guidance. Postoperatively, rATG (1 case) or Simulect (3 cases) was administered for immune induction. Steroids were discontinued, and immunosuppression (cyclosporine + mycophenolate sodium) was maintained. Anti-inflammatory (etanercept), immunomodulatory, and portal pressure-lowering therapies were applied. Insulin was withdrawn after the islet transplantation, with follow-up after discharge (10–14 days post-surgery).
Results: Post-transplant blood glucose levels significantly decreased. Transient hypoglycemia occurred early but resolved within a week. Insulin was discontinued by day 1 post-transplant, and C-peptide levels increased. No surgical complications occurred. One case showed mild transaminase elevation, managed with hepatoprotective drugs. Follow-up revealed normal glucose levels. Steroid-free immunosuppression (cyclosporine + mycophenolate sodium) was maintained, and kidney function remained stable.
Conclusion: Portal vein allogeneic islet transplantation is effective and safe for type 2 diabetes, particularly in kidney transplant recipients on long-term immunosuppression. Even with suboptimal islet counts (<300,000 IEQ), favorable outcomes were achieved. rATG induction may reduce graft loss, and low-toxicity immunosuppressive regimens support long-term graft function.Especially for the fourth patient, a good effect of insulin indenpendence could still be achieved after a low number of islet transplantation.