Membranous nephropathy associated with donor lymphocyte infusion following allogeneic bone marrow transplantation.

Nephrotic syndrome after hematopoietic stem cell transplantation (HSCT) followed by donor lymphocyte infusion (DLI) has never been described. We report the case of a myelodysplastic syndrome (MDS) patient who developed nephrotic syndrome with membranous nephropathy 18 months after allogeneic HSCT and 4 months after DLI. A 50-year-old woman with MDS underwent allogeneic bone marrow transplantation from her HLA-matched brother. MDS relapsed 55 days after transplantation, donor lymphocytes were infused as adoptive immunotherapy, and complete remission was achieved. Four months after the third DLI, the patient developed nephrotic syndrome with proteinuria up to 9 g/day. Renal biopsy revealed granular deposits of immunoglobulin G along the glomerular basement membrane, and subepithelial electron-dense deposits. A diagnosis of membranous nephropathy was made. For maintenance of the immunotherapeutic effect of DLI, minimum doses of immunosuppressive therapy for decreasing proteinuria were administered, and improvement of nephrotic syndrome and persistent complete remission of MDS were achieved.