Spontaneous remission of de novo membranous nephropathy in post-allogeneic hematopoietic stem cell transplantation patients: A report of two cases.

Membranous nephropathy (MN) is one of the most common de novo glomerular diseases developing in patients after allogeneic hematopoietic stem cell transplantation (HSCT). Most authors have used immunosuppression for its treatment to target the underlying immune-mediated processes, akin to graft-versus-host disease, but the optimal management is currently unclear. Limited reports in the literature described the use of a conservative approach with success, particularly in cases with lower risks of progression, such as non-nephrotic-range proteinuria or early reduction of proteinuria by 6 months. We report two cases of post-HSCT MN with moderate risk features, namely prolonged durations of nephrotic-range proteinuria, that spontaneously resolved with conservative treatment. Patient 1 was of advanced age and in an immunocompromised state, while patient 2 was in need of a greater graft-versus-disease effect from the donor's immune system, which necessitated a balance between the risk of immunosuppression and the risk of progressive kidney function loss. These cases demonstrated that conservative treatment can be a reasonable approach in selected patients with post-HSCT MN, including those with moderate risk.