GBM antibodies occur in patients suffering from Goodpasture syndrome, anti-GBMdisease and ANCA associated vasculitis. Goodpasture syndrome is defined by the combined occurrence of progressive glomerulonephritis, lung haemorrhage and antibodies to the glomerular basement membrane (GBM). A more limited form only involving the kidney or the lung is referred to as anti-GBM disease. For the diagnosis of both, Goodpasture syndrome and anti-GBM-disease, the presence of GBM antibodies is required. Furthermore up to 10 % of ANCA positive patients show GBM antibodies, which indicate a more severe course of renal damage.