Co-existing post-transplant membranous nephropathy and diabetic nephropathy: A case report

•Co-existing membranous nephropathy and diabetic nephropathy post-transplant.•Allograft biopsy revealed histological features of both MN and DN.•Both disease processes combined may have resulted in a worse outcome.•Immunosuppression and best supportive care were provided with limited benefit.

Membranous nephropathy (MN) is a glomerular disease commonly found in transplanted kidneys. The natural history of MN post-transplant is unpredictable and spontaneous remission is uncommon. Diabetic nephropathy (DN) is also commonly seen in patients with prolonged new onset diabetes mellitus after transplant (NODAT). However, there have been no previous reports of co-existing MN and DN in transplanted kidneys. We herein report a case of a 53-year-old male with early post-transplant proteinuria and microscopic hematuria due to MN with subsequent clinical spontaneous remission. Due to the early onset of disease after transplant and presence of serum anti-phospholipase A2 receptor (anti-PLA2R) antibody, the evidence suggests primary recurrent MN in this patient. He was then diagnosed with NODAT, with fair glycemic control with oral hypoglycemic agents. Sixteen years after remission, he developed recurrent proteinuria and progressive impairment of renal function. The allograft biopsy revealed both MN and DN. Both diseases may have contributed to the development of glomerular pathology in this patient.