De novo proliferative glomerulonephritis with monoclonal IgG deposits in an adolescent kidney transplant recipient.

Proliferative Glomerulonephritis with Monoclonal IgG Deposits (PGNMID) is a glomerular disease characterized by membranoproliferative and mesangioproliferative lesions, with granular capillary wall monoclonal IgG positivity and immunoglobulin light chain restriction. Most commonly a disease of older adults, we present the case of an 18-year-old patient who developed de novo PGNMID in a kidney allograft three years after kidney transplantation. There was minimal proteinuria and no serum paraproteinemia was detected, so the patient was managed conservatively. To our knowledge, this is the youngest reported case of de novo PGNMID occurring in a kidney allograft and highlights the importance of considering PGNMID as a possible etiology of de novo glomerular disease in adolescent and young adult patients.