[Rapid progressive glomerulonephritis]

The rapid progressive glomerulonephritis is an emergency case. Renal function is rapidly lost within weeks or a few months (rarely within days) due to necrotizing extracapillary proliferative crescentic glomerulonephritis. Early diagnosis and treatment improve prognosis, as the best prognostic marker is creatinine when treatment is initiated. Three classes can be distinguished by immunofluorescence in histology. Firstly, there are no or only few immunoglobulins found (anti-neutrophil cytoplasmic antibody [ANCA]-associated vasculitis). Secondly, there is linear immunofluorescence due to antibodies against the glomerular basement membrane (anti-glomerular basement membrane [GBM] disease or Goodpasture syndrome); and thirdly, there is a granular pattern of immunoglobulin deposition (for example systemic lupus erythematosus [SLE], Schoenlein-Henoch purpura or cryoglobulinaemia). The immunosuppressive repertoire has improved (such as induction therapy in ANCA-associated vasculitis with lower total steroid dose, cyclophosphamide pulses or rituximab). New treatment approaches are on their way and the prognosis regarding life expectancy and renal function has improved. There are still challenging questions to answer like treatment duration and markers of recurrence.