Serum protein that get filtered into primary urine are readily absorbed. If protein is present in urine sample it usually means some damage to renal structures or excess of some pathologic protein in serum.

With gross proteinuria hypoproteinemia can develop and it results in diminished oncotic pressure (ascites, edema, hydrothorax).

Proteinuria is a leading symptom of:

• nephrotic syndromes
• eclampsia
• toxic lesions of kidneys