Proteinuria (from protein and urine) means the presence of an excess of serum proteins in the urine.

Proteinuria may be a sign of renal (kidney) damage. Since serum proteins are readily reabsorbed from urine, the presence of excess protein indicates either an insufficiency of absorption or impaired filtration. Diabetics usually suffer from damaged nephrons and develop proteinuria.

With severe proteinuria, general hypoproteinemia can develop which results in diminished oncotic pressure. Symptoms of diminished oncotic pressure may include ascites, edema, and hydrothorax.

Conditions with proteinuria as a symptom

• nephrotic syndromes (i.e. intrinsic renal failure)
• eclampsia
• toxic lesions of kidneys
• Lupus erythematosus
• glomerular diseases, such as membranous glomerulopathy, focal segmental glomerulonephritis, minimal change disease (lipoid nephrosis)

See also

• albuminuria
• microalbuminuria
• List of terms associated with diabetes

Nephrology | Medical signs

Proteinurie | Proteinuria | Protéinurie | 蛋白尿