[Membranous glomerulonephritis : An example of individualized medicine in nephrology]

Membranous glomerulonephritis (MGN) is the most frequent cause of a nephrotic syndrome in adults. It is an autoimmune disease caused by binding of autoantibodies to endogenous proteins expressed on glomerular podocytes. Antibody binding and activation of inflammatory mediators result in the onset of proteinuria. Recently, two endogenous podocytic target antigens in MGN have been characterized and their clinical role is a main focus of research in nephrology.

The discovery that antibodies against phospholipase A2 receptor 1 (PLA₂R1) and thrombospondin type 1 domain containing 7A (THSD7A) mediate the pathogenesis of MGN leads to the question of what clinical role these antibodies have in patients with MGN.

Evidence published in recent years on the role of the described antigens is analyzed and critically discussed. The clinical conclusions derived for patients with MGN are presented.

Antibodies against PLA₂R1 are detectable in approximately 80% of patients with MGN, while 2-3% of patients have antibodies against THSD7A. Serum analyses of antibodies and immunohistological staining in kidney biopsies enable an almost 100% certain diagnosis of PLA₂R1 and THSD7A-mediated MGN. Serum levels of PLA₂R1 antibodies are predictors for the response to therapy, determine the prognosis and allow an exact individualized monitoring of treatment. The THSD7A antibodies are associated with an increased prevalence of malignant tumors and play a pathogenetic role in the genesis of this secondary form of MGN.

The characterization of the antibodies responsible for the development of MGN is an example of precision medicine in nephrology and the foundation for the development of new, curative treatments.