What does high protein in urine mean?

Question

What are the possible causes of the presence of high levels of protein in urine?

Answer

In the absence of other symptoms I can only give a very general answer to this question.

The kidneys' primary function is to maintain the fluid balance in the body and to excrete unwanted soluble chemicals. While doing this, the kidneys must conserve other important constituents circulating in the bloodstream.

Although healthy people do pass small amounts of protein in the urine normally, above a certain level suggests that there may be damage to the filter mechanism (the glomeruli) or inflammation.

A second source of protein in urine is blood that may come from any part of the kidney or urinary pathway.

High levels of protein in the urine may therefore be due to diseases of the kidney such as glomerulonephritis. It may also be due to general illnesses that also affect the kidney as in high blood pressure or heart failure.

Infections of the renal pathway such as  cystitis or pyelonephritis may cause a high level of protein in the urine.

This finding is an important part of investigations for several conditions and is extremely important when considered with other symptoms that together indicate the cause.

Reference: http://www.netdoctor.co.uk/ate/liverandkidney/203137.html