Membranous nephropathy (MN) is one of the most common causes of nephrotic syndrome in native kidney biopsies from adults. In 2009, antibodies to the M-type receptor of phospholipase A2 (anti-PLA2R) were identified in idiopathic MN patients, both within the kidney and in the circulation. The clinical course of idiopathic MN is variable and ranges from spontaneous remission to end-stage renal disease. Clinical variables such as proteinuria levels, patient sex, age and renal function at diagnosis have been associated with renal MN progression. In this editorial, we update the importance of anti-PLA2R levels as a prognostic marker in idiopathic MN at the diagnosis of the disease.