What's New in Membranous Nephropathy and How to Incorporate New Antigen Discoveries Into Clinical Practice: A Review.

Membranous nephropathy (MN) is one of the most common causes of nephrotic syndrome in adults and can be seen in association with other diseases, including malignancy, drugs, infections, or autoimmune diseases. Over the last decade, great progress has been made in understanding the pathogenesis of the disease, resulting from the discovery of several target antigens by use of laser microdissection/mass spectrometry methodology. This technique has proven to be the most sensitive method available and has the advantage of testing for all the target antigens at one time. The discovery of these target antigens has now shifted the classification of MN from primary versus secondary to classification based on the target antigen identified. Each target antigen has its own specific clinical characteristics and known associated diseases. Identification of the target antigen can help further identify the underlying cause for a more targeted approach in looking for associated diseases. Progress has also been made in the treatment of patients with MN, with more standard risk stratification of the patients and a shift in using anti-CD20 drugs as the first line for those with moderate and high risk of progression. Trials are ongoing to further investigate the role of anti-plasma cell, anticomplement, and CAR-T (chimeric antigen receptor T-cell) therapies.