Protein in Urine: Test Results & What They Mean

Protein in urine means protein is leaking from your blood into your urine, which suggests the kidney's filtering units may be damaged. Healthy kidneys keep most protein, especially albumin, in the blood, so urine should contain very little or none. Doctors call this proteinuria, or albuminuria when the protein is albumin. It can be an early sign of kidney disease even when your eGFR is normal. A result does not name a cause on its own. Your doctor will usually order follow-up testing, such as a uACR test, and read the result with your other tests and health history.

Not necessarily. Protein in urine points first to the kidneys, not the liver. Diabetes and high blood pressure are the most common causes of chronic kidney disease. Liver and kidney problems can also occur together, for example in advanced cirrhosis, where kidney injury such as hepatorenal syndrome can develop. For that reason, your team may look at both organs. The protein finding more directly tied to the liver is low albumin in the blood, because the liver makes albumin. Low blood albumin can be a sign of liver damage.

Healthy kidneys let very little or no albumin into urine. A dipstick uses a color-change strip to screen for protein. A uACR test compares albumin with creatinine, a waste product from normal muscle breakdown, to measure how much albumin is leaking. A higher uACR stage means more kidney damage and a higher risk that the disease will progress. Your lab and doctor set the exact cutoffs, and lab ranges can differ, so ask how your result is staged and what it means for you.

No. A urinalysis is a simple test on a urine sample, with no needles. You give a sample in a cup, and a technician dips a test strip into it. The sample may also be checked by eye for color and clearness, and a small amount may be viewed under a microscope. The dipstick is a quick screen. If it finds protein, a uACR test gives a closer measurement, and it also uses a urine sample.

Yes, and this is common. Early kidney disease often causes few or no symptoms, and chronic kidney disease can still cause damage while you feel fine. That is why a urine test can catch a problem early. Possible signs include foamy urine, swelling around the hands, ankles, or face, extreme tiredness, and a change in how often you pee. Call your care team if you notice any of these. If you have cirrhosis, tell your team promptly.

Not usually. For adults with stable cirrhosis, guidance calls for 1.2 to 1.5 grams of protein per kilogram of body weight per day, to prevent loss of muscle mass and support liver function. Cutting protein is discouraged in decompensated cirrhosis with hepatic encephalopathy. Restricting protein was once common but is now known to be harmful. People with hepatic encephalopathy may tolerate vegetable and dairy proteins better than red meat. Ask your care team for your own target, especially if you also have kidney disease.