is deposition of immune complexes on the (GBM) with GBM thickening. Cause is usually unknown, although secondary causes include drugs, infections, , and Manifestations include insidious onset of edema and heavy proteinuria with benign urinary sediment, normal renal function, and normal or elevated BP.
75% of adult and 20% of childhood cases are idiopathic autoimmune disease linked to HLA, caused by antibodies to a renal autoantigen. Secondary cases are associated with cancer (lung, colon, melanoma), B/C, malaria, schistosomiasis, drugs (penicillamine, captopril, gold, NSAID), heavy metals, lupus, diabetes,and angiofollicular lymph node hyperplasia. Proteinuria may be due to C5b-C9 (MAC complex of complement) recurrences represent idiopathic MGN due to IgG4, with different pathogenic mechanism than de novo MGN.
There were 444 native kidney biopsies performed, 238 males (53.6%) and 206 females (46.7%). The average age of patients was 47.6 years. The most common clinical presentation as an indication for renal biopsy was nephrotic syndrome (52%). Membranous nephropathy (17.5%) was the most common glomerular disease and the most frequent cause (29.8%) of nephrotic syndrome.
The controversy is mainly related to the toxicity of the therapy and the variable natural course of the disease—spontaneous remission occurs in 40–50% of patients. The 2012 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Glomerulonephritis provides guidance for the treatment of iMN. The guideline suggests that immunosuppressive therapy should be restricted to patients with nephrotic syndrome and persistent proteinuria, deteriorating renal function or severe symptoms.
Major research on disease:
New physiopathological roles for the PLA2R1 receptor in cancer and membranous nephropathy. PLA2R1 is a large transmembrane receptor of 180-kDa that belongs to the superfamily of C-type lectins. It was discovered because of its high affinity for secreted phospholipases A2 (sPLA2), enzymes that play a key role in lipid mediator synthesis.