What is Proteinuria

Proteinuria is when there is too much protein in the urine. Proteins are important for building muscles and bones. Proteins are also needed to fight infections, help the blood clot, and keep body fluids in balance.

Proteinuria may be mild and temporary, or it may be an early sign of kidney disease. The kidneys make urine. Healthy kidneys also keep substances like proteins from leaving the blood and ending up in the urine. Proteinuria may be a sign that the kidneys are not working well.

What are the causes?

Healthy kidneys have filters (glomeruli) that keep proteins out of the urine. Proteinuria may mean that the glomeruli are damaged. The main causes of this type of damage are:

• Diabetes.
• High blood pressure.

Other causes of kidney damage can also cause proteinuria, such as:

• Diseases of the immune system, such as lupus, rheumatoid arthritis, sarcoidosis, and Goodpasture syndrome.
• Heart disease or heart failure.
• Kidney infection.
• Certain cancers, including kidney cancer, lymphoma, leukemia, and multiple myeloma.
• Amyloidosis. This is a disease that causes abnormal proteins to build up in body tissues.
• Reactions to certain medicines, such as NSAIDs.
• Injury (trauma) or poisons (toxins).
• High blood pressure that occurs during pregnancy (preeclampsia).

Temporary proteinuria may result from conditions that put stress on the kidneys. These conditions usually do not cause kidney damage. They include:

• Fever.
• Exposure to cold or heat.
• Emotional or physical stress.
• Extreme exercise.
• Standing for long periods of time.

What increases the risk?

This condition is more likely to develop in people who:

• Have diabetes.
• Have high blood pressure.
• Have heart disease or heart failure.
• Have an immune disease, cancer, or other disease that affects the kidneys.
• Have a family history of kidney disease.
• Are 65 or older.
• Are overweight.
• Are of African-American, American Indian, Hispanic/Latino, or Pacific Islander descent.
• Are pregnant.
• Have an infection.

What are the signs or symptoms?

Mild proteinuria may not cause symptoms. As more proteins enter the urine, symptoms of kidney disease may develop, such as:

• Foamy urine.
• Swelling of the face, abdomen, hands, legs, or feet (edema).
• Needing to urinate frequently.
• Fatigue.
• Difficulty sleeping.
• Dry and itchy skin.
• Nausea and vomiting.
• Muscle cramps.
• Shortness of breath.

How is this diagnosed?

Your health care provider can diagnose proteinuria with a urine test. You may have this test as part of a routine physical or because you have symptoms of kidney disease or risk factors for kidney disease. You may also have:

• Blood tests to measure the level of a certain substance (creatinine) that increases with kidney disease.
• Imaging tests of your kidney, such as a CT scan or an ultrasound, to look for signs of kidney damage.

How is this treated?

If your proteinuria is mild or temporary, no treatment may be needed. Your health care provider may show you how to monitor the level of protein in your urine at home. Identifying proteinuria early is important so that the cause of the condition can be treated.

Treatment depends on the cause of your proteinuria. Treatment may include:

• Making diet and lifestyle changes.
• Getting blood pressure under control.
• Getting blood sugar under control, if you have diabetes.
• Managing any other medical conditions you have that affect your kidneys.
• Giving birth, if you are pregnant.
• Avoiding medicines that damage your kidneys.
• Treating kidney disease with medicine and dialysis, as needed.

Follow these instructions at home:

• Check your protein levels at home, if directed by your health care provider.
• Follow instructions from your health care provider about eating or drinking restrictions.
• Take over-the-counter and prescription medicines only as told by your health care provider.
• Return to your normal activities as told by your health care provider. Ask your health care provider what activities are safe for you.
• If you are overweight, ask your health care provider to help you with a diet to get to a healthy weight.
• Ask your health care provider to help you with an exercise program.
• Keep all follow-up visits as told by your health care provider. This is important.

Contact a health care provider if:

• You have new symptoms.
• Your symptoms get worse or do not improve.

Get help right away if:

• You have back pain.
• You have diarrhea.
• You vomit.
• You have a fever.
• You have a rash.