Everyone has protein in their blood. The main protein in your blood is called albumin. Proteins have many important jobs in your body, such as helping to build your bones and muscles, prevent infection and control the amount of fluid in your blood.
Healthy kidneys remove extra fluid and waste from your blood, but let proteins and other important nutrients pass through and return to your blood stream. When your kidneys are not working as well as they should, they can let some protein (albumin) escape through their filters, into your urine. When you have protein in your urine, it is called proteinuria (or albuminuria). Having protein in your urine can be an early sign of kidney disease.
Anyone can have protein in their urine. You may be more at risk for having it if you have one or more of the risk factors for kidney disease, such as:
- High blood pressure
- Family history of kidney disease
How will I know if I have protein in my urine?
When your kidneys are first starting to have problems, and you do not have a lot of protein in your urine, you will not notice any symptoms. The only way to know if you have protein in your urine is to have a urine test. The test for protein in the urine measures the amount of albumin in your urine, compared to the amount of creatinine in your urine. This is called the urine albumin-to-creatinine ratio (UACR). A UACR more than 30 mg/g can be a sign of kidney disease.
When your kidney damage gets worse and large amounts of protein escape through your urine, you may notice the following symptoms:
- Foamy or bubbly-looking urine when you use the toilet
- Swelling in your hands, feet, abdomen or face
If you are having these symptoms, your kidney damage may already be severe. Talk to your health care provider immediately about what may be causing your symptoms and what treatment is best for you.
How is proteinuria treated?
If you have diabetes, controlling it will mean checking your blood sugar often, taking medicines as your doctor tells you to, and following a healthy eating and exercise plan. If you have high blood pressure, your doctor may tell you to take a medicine to help lower your blood pressure and protect your kidneys from further damage. The types of medicine that can help with blood pressure and proteinuria are called angiotensin-converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers (ARBs).
If you have protein in your urine, but you do not have diabetes or high blood pressure, an ACE inhibitor or an ARB may still help to protect your kidneys from further damage. If you have protein in your urine, talk to your doctor about choosing the best treatment option for you.