Primary membranous nephropathy

Disease information

Primary membranous nephropathy (pMN) is a chronic disease of the renal glomeruli that results in impairment of the renal functions. The disease bears an autoimmune etiology. It is instigated by the autoantibodies that are directed against glycoprotein phospholipase A2 receptor (PLA2R) and thrombospondin type 1 domain containing protein 7A (THSD7A). These antibodies react against the podocytes surrounding the renal glomeruli causing them significant damage. The result is leakage of the proteins in the urine (proteinuria).

Primary membranous nephropathy (pMN) is a leading cause of nephrotic syndrome in adults. Peak incidence is seen in light-complexioned males over 40 years of age. In women however, lupus nephritis is always suspected and considered with pMN. Primary membranous nephropathy is very rare in children.

Secondary pMN
Primary membranous nephropathy has to be differentiated from secondary pMN which is seen usually after infections, drug therapy and toxins. Early diagnosis and prompt treatment improves disease prognosis with respect to nephrotic syndrome and hypertonicity.