How is pathogenesis of rapidly progressive glomerulonephritis?

➢ RPGN may be associated with a number of diseases, as follows: 1. Anti-GBM antibody–mediated crescentic GN (Goodpasture disease) : linear deposits of IgG and, in many cases, C3 in the GBM. In some patients, the anti-GBM antibodies also bind to pulmonary alveolar capillary basement membranes to produce the clinical picture of pulmonary hemorrhages associated with renal failure : Goodpasture syndrome 2. Immune complex–mediated crescentic GN may complicate any of the immune complex nephritis, including post- treptococcal GN, systemic lupus erythematosus, IgA nephropathy, and HenochSchönlein purpura This type of RPGN frequently shows cellular proliferation and influx of leukocytes within the glomerular tuft, in addition to cres-cent formation. A consistent finding is the characteristic granular pattern of staining of the GBM and/or mesangium for immunoglobulin and/or complement on immunofluorescence studies. 3. Pauci-immune type crescentic GN is defined by the lack of anti-GBM antibodies or significant immune complex deposition. Anti-neutrophil cytoplasmic antibodies (ANCA) typically are found in the serum. In some instances crescentic GN is a component of a systemic vasculitis such as microscopic polyangiitis or granulomatosis with polyangiitis.