cause of oedema in Glomenulonephritis is :
The nephrotic oedema is classically more severe and marked and is present in the subcutaneous tissues as well as in the visceral organs. The affected organ is enlarged and heavy with tense capsule.
Microscopically, the oedema fluid separates the connective tissue fibres of subcutaneous tissues. Depending upon the protein content, the oedema fluid may appear homogenous, pale, eosinophilic or may be deeply eosinophilic and granular.
Oedema in glomerulonephritis. Oedema occurs in conditions with diffuse glomerular disease such as in acute diffuse glomerulonephritis and rapidly progressive glomerulonephritis (nephritic oedema). In contrast to nephrotic oedema, nephritic oedema is not due to hypoproteinaemia but is due to excessive reabsorption of sodium and water in the renal tubules via renin-angiotensin-aldosterone mechanism. The protein content of oedema fluid in glomerulonephritis is quite low (less than 0.5 g / dl).
The nephritic oedema is usually mild as compared to nephrotic oedema and begins in the loose tissue such as on the face around eyes, ankles and genitalia. Oedema in these conditions is usually not affected by gravity (unlike cardiac oedema).
Increased hydrostatic pressure.
Sodium and water retention.
Lymphatic obstruction.
Reduced plasma oncotic pressure.