[CDISC Definition]: Inflammatory changes in the renal glomeruli characterized by thickening of the glomerular basement membrane, mesangial cell proliferation and/or mononuclear inflammatory cell infiltration. In some forms, the glomerular epithelial cells may also proliferate and form adhesions.

[NICHD Definition]: Inflammation of the glomeruli that can extend to other parts of the kidney.

[HPO Definition]: Inflammation of the renal glomeruli. [HPO:probinson]

[GARD Definition]: Glomerulonephritis is a type of kidney disease in which there is inflammation of the glomeruli, the tiny filters that remove excess waste and fluids from the blood.  It may be acute or chronic (coming on gradually), and may occur on its own (primary) or be caused by another condition (secondary). Signs and symptoms may depend on the type and cause of the condition and may include blood in the urine; foamy urine; swelling of the face, eyes, or other body parts; abdominal pain; high blood pressure; fatigue; and/or other symptoms. If the condition is severe or prolonged, the kidneys can become damaged.  It may be caused by a variety of infections and diseases, and sometimes the cause is unknown. Treatment depends on the cause, type and severity of the condition. - this information is from GARD/ORDR/NCATS.

[NCIt Definition]: A renal disorder characterized by damage in the glomeruli. It may be acute or chronic, focal or diffuse, and it may lead to renal failure. Causes include autoimmune disorders, infections, diabetes, and malignancies.