Rapidly progressive glomerulonephritis is a term used to describe a rapid loss of renal function associated with the formation of epithelial crescents in the majority of glomeruli.
- Patients are often significantly oliguric.
- It can be broadly grouped into 3 types as described below.
Features
- nephritic syndrome: haematuria with red cell casts, proteinuria, hypertension, oliguria
- features specific to underlying cause (e.g. haemoptysis with Goodpasture's, vasculitic rash or sinusitis with Wegener's)
Type I
- Anti-Glomerular Basement Membrane (GBM) antibody disease.
- This is characterised by linear deposits of IgG in the basement membrane seen on immunofluorescence.
- In a subset of these patients, these anti-GBM antibodies cross react with antigens on the alveolar basement membrane.
- This can produce pulmonary haemorrhage associated with renal failure, the typical picture associated with Goodpasture's syndrome.
Type II
- Immune complex deposition disease.
- This is a complication of any of the immune complex nephritic diseases.
- This includes post-streptococcal GN, Lupus nephritis, IgA nephropathy, Henoch-Schonlein purpura.
- Type II RPGN is typically characterised by a granular pattern of staining on immunofluorescence studies, this granular pattern is typical for immune complex deposition.
Type III