There are three main mechanisms to cause urinary protein:
1.Due to disease in the glomerulus
2.Because of increased quantity of proteins in serum (overflow proteinuria)
3.Due to low reabsorption at proximal tubule (Fanconi syndrome)
Proteinuria can also be caused by certain biological agents,such as bevacizumab (Avastin) used in cancer treatment,or by excessive fluid intake (drinking in excess of 4 litres of water per day).

Also leptin administration to normotensive Sprague Dawley rats during pregnancy significantly increases urinary protein excretion

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.People with diabetes may have damaged nephrons and develop proteinuria.The most common cause of proteinuria is diabetes,and in any person with proteinuria and diabetes,the etiology of the underlying proteinuria should be separated into two categories: diabetic proteinuria versus the field.

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



Treatment
Treating proteinuria mainly needs proper diagnosis of the cause.The most common cause is diabetic nephropathy;in this case,proper glycemic control may slow the progression.Medical management consists of angiotensin converting enzyme (ACE) inhibitors,which are typically first-line therapy for proteinuria.In patients whose proteinuria is not controlled with ACE inhibitors,the addition of an aldosterone antagonist (i.e.,spironolactone)or angiotensin receptor blocker (ARB) may further reduce protein loss.Caution must be used if these agents are added to ACE inhibitor therapy due to the risk of hyperkalemia.Proteinuria secondary to autoimmune disease should be treated with steroids or steroid-sparing agent plus the use of ACE inhibitors.

Related Posts
Urine dipstick features
A urine test strip or dipstick test is a basic diagnostic tool used to determine pathological changes in a patient’s urine in standard urinalysis......
The use of urine
Urine (from Latin Urina,ae,f.) is a liquid by-product of the body secreted by the kidneys through a process called urination (or micturition) and excreted through the urethra......