Discovery of autoantibodies targeting nephrin in minimal change disease supports a novel autoimmune etiology

Minimal change disease (MCD) is a common diagnosis in children and adults, and can be sparked by triggers such as infections or vaccination.  While a B-cell etiology was already suspected, a recent paper goes a step further. The authors show that nephrin autoantibodies are present in a subset of patients with active MCD, correlate with disease activity and associate with the presence of punctate IgG in the biopsy (colocalizing with nephrin) as evaluated by IF studies. Moreover, a case report of a 27-year old patient known with MCD is presented where pretransplant nephrin antibodies associate with massive proteinuria recurrence after transplantation. Although many questions remain, this is an exciting paper on disease mechanism in one of the most common proteinuric diseases and it invites us all to look more closely at IF in MCD.