Membranous nephropathy

Membranous glomerulonephritis (MGN) is a slowly progressive disease of the kidney affecting mostly people between ages of 30 and 50 years, usually Caucasian. Membranous glomerulonephritis (MGN) is a slowly progressive disease of the kidney affecting mostly people between ages of 30 and 50 years, usually Caucasian. It is the second most common cause of nephrotic syndrome in adults, with focal segmental glomerulosclerosis (FSGS) recently becoming the most common. Some people may present as nephrotic syndrome with proteinuria, edema with or without kidney failure. Others may not have symptoms and may be picked up on screening or urinalysis as having high amounts of protein loss in the urine. A definitive diagnosis of membranous nephropathy requires a kidney biopsy. 85% of MGN cases are classified as primary membranous glomerulonephritis—that is to say, the cause of the disease is idiopathic (of unknown origin or cause). This can also be referred to as idiopathic membranous nephropathy. One study has identified antibodies to an M-type phospholipase A2 receptor in 70% (26 of 37) cases evaluated. In 2014, a second autoantigen was discovered, the thrombospondin type 1 domain-containing 7A (THSD7A) system that might account for an additional 5-10% of membranous nephropathy cases. Other studies have implicated neutral endopeptidase and cationic bovine serum albumin as antigens.