Preserved insulin secretion and kidney function in recipients with functional pancreas grafts 1 year after transplantation: a single-center prospective observational study.

Objective: Successful simultaneous pancreas and kidney transplantation (SPK) or pancreas transplantation alone (PTA) restores glycemic control. Diabetes and impaired kidney function are common side effects of immunosuppressive therapy. This study addresses glucometabolic parameters and kidney function during the first year.

Methods: We examined 67 patients with functioning grafts (SPK n = 30, PTA n = 37) transplanted between September 2011 and November 2016 who underwent repeated oral glucose tolerance tests (OGTTs) 8 and 52 weeks after transplantation. Another 19 patients lost their graft the first year post-transplant and 28 patients did not undergo repeated OGTTs and could not be studied. All patients received ATG induction therapy plus tacrolimus, mycophenolate and prednisolone. Glomerular filtration rate was measured before and 8 and 52 weeks after transplantation by serum clearance methods.

Results: From week 8 to 52 after transplantation, mean fasting glucose decreased (SPK: 5.4 ± 0.7 to 5.1 ± 0.8 mmol/L, PTA: 5.4 ± 0.6 to 5.2 ± 0.7 mmol/L; both P < 0.05), and also 120-min post-OGTT glucose (SPK: 6.9 ± 2.9 to 5.7 ± 2.2 mmol/L; P = 0.07, PTA: 6.5 ± 1.7 to 5.7 ± 1.2 mmol/L; P < 0.05). Fasting C-peptide levels also decreased (SPK: 1500 ± 573 to 1078 ± 357 pmol/L, PTA: 1210 ± 487 to 1021 ± 434 pmol/L, both P < 0.005). Measured GFR decreased from enlistment to 8 weeks post transplant in PTA patients (94 ± 22 to 78 ± 19 mL/min/1.73 m2; P < 0.005), but did not deteriorate from week 8 to week 52 (SPK: 55.0 ± 15.1 vs 59.7 ± 11.3 ml/min/1.73 m²; P = 0.19, PTA: 76 ± 19 vs 77 ± 19 mL/min/1.73 m²; P = 0.74).

Conclusion: Glycemic control and kidney function remain preserved in recipients with functioning SPK and PTA grafts 1 year after transplantation.