[Update nephrotic syndrome - new pathophysiologic concepts 2022].

The identification of autoantibodies responsible for the development of membranous nephropathy (MN) in most patients, has led to the development of antigen-specific diagnosis and treatment options for this disease. Pathomechanisms leading to the initiation of the immune response against PLA2R1 are not clear, yet. Environmental and genetic factors may play a role in these processes. In THSD7A-induced MN THSD7A-expressing tumors may play an important pathogenic role.An antigen-specific diagnosis of MN is important for the development of individualized disease management strategies in these patients. These strategies include for example tumor screening, the decision to perform a kidney biopsy, adjustment of treatment based on the immunologic disease activity, better estimation of the risk for disease progression as well as the prognosis of disease etc. The clinical role of domain-specific PLA2R1-antibodies needs to be better defined. In the last years, several novel target antigens have been described in patients with MN. The pathogenetic role of these antigens needs to be better defined.In MCD and FSGS a T-cell disruption is assumed to play a central role for disease pathogenesis, which, however, remains not well understood. In the last years, a potential role for B-cells and autoantibodies has been postulated in these patients. For both MCD and FSGS steroids remain the first line treatment strategy. When a steroid treatment needs to be avoided, calcineurin inhibitors are often used as a second line therapy. Other treatment options include cyclophosphamide, MMF and rituximab.