Glomerulonephritis
（重定向自Glomerulitis）
![](/Images/godic/202501/15/Crescentic_glomerulonephritis_HE_stain2307.JPEG")
![A glomerulus, a functional unit that represents the first step in the filtration of blood and generation of urine.](/Images/godic/202501/15/Gray1130.svg2307.png")
![Podocytes, cells which line the glomerulus, are negatively charged and have small gaps, preventing the filtration of large molecules. When damaged by inflammation, this can result in an increased permeability to proteins](/Images/godic/202501/15/Filtration_barrier.svg2307.png")
![Crescentic glomerulonephritis induced by infective endocarditis on PAS staining and immunofluorescence. PAS staining (left) demonstrated circumferential and cellular crescent formation with interstitial nephritis. Immunofluorescence (right) demonstrated C3 positive staining in mesangial area.](/Images/godic/202501/15/Crescentic_glomerulonephritis_PAS_and_IF2307.png")
Glomerulonephritis (GN), also known as glomerular nephritis, is a term used to refer to several kidney diseases (usually affecting both kidneys). Many of the diseases are characterised by inflammation either of the glomeruli or of the small blood vessels in the kidneys, hence the name, but not all diseases necessarily have an inflammatory component.