When kidneys are not functioning properly, protein may escape from the blood into urine and protein levels will not be normal. Blood (serum) levels of protein may be too low and urine levels of protein may be too high.
Laboratory tests check for levels of a protein called albumin in urine and blood. In a random urine sample, a range of 0 to 8 and sometimes 10 mg/dL protein is considered normal, according to University of Maryland Medical Center. Normal blood levels range from 3.4 to 5.4 g/dL.
Abnormal amounts of protein found in the urine or blood during routine laboratory work may be the first indication of kidney disease such as glomerulonephritis or other significant health problems.
A high protein level in urine is called proteinuria, and a high level of albumin, specifically, is referred to as albuminuria.
To return protein levels to normal and protect kidney function, doctors may prescribe blood pressure medication such as angiotensin-converting enzyme (ACE) inhibitors, even if you don't have high blood pressure.
Higher than normal levels of protein in the urine may be due to dehydration or bacterial (urinary tract) infection unrelated to kidney disease. In these cases, protein levels return to normal when hydration occurs or infection is cleared.