Table of ContentsView AllTable of ContentsSymptomsCausesTreatmentDiagnosisWhen to See a Provider
Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Treatment
Diagnosis
When to See a Provider
Proteinuriais the presence of too much protein in the urine. It is typically a sign ofkidney disease, often in people diagnosed with diabetes, but also can occur withpregnancy,lupus, and other health conditions.One of the main signs of proteinuria is foamy urine, but that can occur in healthy people, too.
Proteinuria often has no symptoms and some studies find that only about a third of cases are linked to kidney disease.In many cases, the underlying cause is never known or the accurate diagnosis relies on other co-occurring symptoms.
A urine dipstick test is central to the diagnosis of proteinuria.blueshot / Getty Images
blueshot / Getty Images
Typically, there is very little protein in your urine. The kidneys provide a filtration barrier that prevents most proteins from leaving the blood, and those that do make it through are simply reabsorbed back into circulation.
Different mechanisms can permit protein to escape into the urine, including even transient proteinuria due to dehydration, or due to postural proteinuria. The latter condition, sometimes callednutcracker syndrome, occurs when when blood vessels are compressed and affects both adults and children.
Foamy urine is not diagnostic of proteinuria. In fact, some people may havebilirubinuria(excess bilirubin in the urine) or retrograde ejaculation (the backflow of semen into the bladder).
If the kidneys have sustained only mild damage, proteinuria may be minimal to moderate, depending upon where in the kidney the damage has occurred.
Foamy Urine as a Sign of ProteinuriaWhile foamy or frothy urine can be a sign of proteinuria, other factors can cause urine to be foamy on occasion. The foaminess should be persistent over time before considering other causes, like decreased kidney function.
Foamy Urine as a Sign of Proteinuria
While foamy or frothy urine can be a sign of proteinuria, other factors can cause urine to be foamy on occasion. The foaminess should be persistent over time before considering other causes, like decreased kidney function.
Nephrotic Syndrome
If the loss of kidney function is severe, proteinuria may be a part of a more serious condition callednephrotic syndrome. This causes fluid buildup anddyslipidemia(unhealthy levels of cholesterol or fats).
Symptoms of nephrotic syndrome include:
Causes of Proteinuria
Kidney disease is usually the first condition a healthcare provider will explore when there is excess protein in the urine. But other conditions can cause proteinuria, some of which occur independently of kidney disease.
Kidney Disease
There are many causes of this, and it is collectively referred to asglomerular disease.
Proteinuria is common with the two main types of kidney disease:
Other conditions that affect the kidney can lead to proteinuria and include:
Overflow Proteinuria
Overflow proteinuria occurs when the amount of low molecular weight proteins in the blood exceeds the amount the kidneys can filter. When this happens, the excess protein exits the body in urine.
Certain conditions can cause overproduction of proteins that, in turn, leads to overflow proteinuria:
Medications
There are certain medications that can cause proteinuria. These drugs are classified asnephrotoxicbecause they are toxic to the kidneys.
Medications and substances commonly associated with nephrotoxicity include:
How to Treat Proteinuria
For instance, the symptoms of acute kidney injury—formerly known as acute kidney failure—will usually clear once the underlying condition is treated. In most cases, the kidney function will return to normal with no permanent damage to the kidneys.
With chronic kidney disease (CKD), the focus is placed on improving the function of the kidneys to slow the progression of the disease, often linked to diabetes and high blood pressure.With respect to proteinuria:
Are There Tests to Diagnose the Cause of Proteinuria?
Diagnosing proteinuriacan be diagnosed with a simple urine test.This involves dipping a specially treated paper strip into a sample of urine. Results are returned within one to two minutes.
To measure the exact amount of protein excreted in the urine, your healthcare provider may recommend a 24-hour urine collection test. By evaluating the composition of urine collected over 24 hours (including different types of proteins and waste products), the lab can calculate how much protein is passed each day.
Urine dipstick tests are commonly performed in a healthcare provider’s office, but there are at-home and mail-in tests that you can use in the privacy of your own home. However, the urine dipstick test may not be as accurate. Talk with your healthcare provider about the urine test.
Levels of Protein in UrineNormal results of a urine test called the urine albumin-creatinine ratio (uACR) fall below 30 milligrams per gram. For levels between 30 and 299 mg, it’s considered moderately high and increases your risk (or a diagnosis, in some cases) of kidney disease. At 300 mg or more, the likelihood of kidney disease is much higher.
Levels of Protein in Urine
Normal results of a urine test called the urine albumin-creatinine ratio (uACR) fall below 30 milligrams per gram. For levels between 30 and 299 mg, it’s considered moderately high and increases your risk (or a diagnosis, in some cases) of kidney disease. At 300 mg or more, the likelihood of kidney disease is much higher.
While these tests can tell you whether or not you have proteinuria, they cannot tell you what caused it if you do. For this, you would need to see a healthcare provider. Other tests may include:
When to See a Healthcare Provider
Proteinuria doesn’t always mean there’s a serious problem, but seek immediate medical care if you experience the following:
These are common signs ofkidney failure, a condition in which the kidney function has dropped so severely that you may require hospitalization to avoid illness or death.This is especially true if the symptoms develop over the span of several hours or days. Without treatment, kidney failure is associated with a high risk of death.
Summary
Proteinuria is the presence of excess presence of protein in the urine. It commonly occurs in people with kidney disease when the filters of the kidneys, called the glomeruli, are damaged.
26 Sources
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