What is proteinuria?

Proteinuria, also called albuminuria, is elevated protein in the urine. It is not a disease in and of itself but a symptom of certain conditions affecting the kidneys. Typically, too much protein in the urine means that the kidneys’ filters — the glomeruli — are not working properly and are allowing too much protein to escape in the urine. When the glomeruli are damaged the condition is called nephritis or glomerulonephritis. Other conditions can lead to nephritis, including hypertension, heart disease and diabetes, as well as other types of kidney disease.

Albumin is the protein most likely to appear in the urine, which is why proteinuria is sometimes called albuminuria. Other proteins can also leak into the urine. The level and type of protein reveals the degree of the damage, as well as the risk for developing kidney failure. If the protein levels are only minimally elevated, the condition is called microalbuminuria and signals minimal damage. However, as the condition progresses, the damage gets worse and more protein escapes into the urine, leading to full-blown albuminuria.

Symptoms

• Foamy urine
• Swelling of the hands, feet, face and/or abdomen

Remember: In the early stages, proteinuria may not cause visible symptoms.

Diagnosis

A fast dipstick urine test can detect protein in the urine. A paper stick dipped in the urine will change color if protein levels are high.

Further tests, however, are needed to determine the exact amount of protein and the ratios of certain proteins to other substances in the urine. More tests are needed to determine the exact cause of proteinuria. These include blood tests to measure creatinine and urea nitrogen, waste materials filtered by the kidneys that are elevated in people with impaired kidney function.

Some organizations and experts recommend routine protein screening for people at high risk for kidney damage. Groups at high risk for kidney failure include African Americans, American Indians, Hispanics/Latinos, Pacific Islander Americans, people with diabetes and/or hypertension and people with family histories of kidney disease.

Treatment

Treatment depends on the underlying cause of the condition. If nephritis is the cause, determining the reason for the kidney inflammation and treating accordingly is the first step. If hypertension or diabetes is the cause, the first goal is to control high blood pressure or blood sugar, respectively.

When to Call for Help

If your child has foamy urine and/or puffiness around the eyes, swelling of the face, hands or feet, talk to your pediatrician.