Protein in urine

 In brief: 

• Normally, there is little or no protein in the urine. 
• When protein is present in the urine for a longer period of time, there is often something wrong with the kidneys. 
• There are several possible causes for too much protein in the urine, such as high blood pressure or diabetes.
• Often no symptoms are present, in some cases a layer of foam can be seen on the urine.
• The diagnosis can be made with a 'dipstick'. This is a rod that changes color as soon as it comes into contact with protein.
• The treatment of protein in the urine usually consists of medication.
• It is advisable to follow a low-salt diet and to apply other lifestyle tips. 

What is protein in urine (proteinuria) ? 

Normally there is little or no protein in your urine. It is normal for there to be temporary protein in your urine, for example after exercise or if you have had the flu. However, if you have too much protein in your urine for a longer period of time, we speak of proteinuria. This often means that something is wrong with your kidneys. If you have protein in your urine for a longer period of time, you will develop symptoms. 

What is a normal and elevated amount of protein in your urine?

At a normal value, you have less than 30 milligrams of protein in your urine per day. At more than 30 milligrams per day, the value is increased. Below you will find the normal and elevated protein values ​​in urine in a row: 

• Normal amount of protein in the urine: Less than 30 milligrams of protein per day. The kidneys work normally.
• Slightly increased amount of protein in the urine: 30 to 300 milligrams of protein per day. This may indicate an onset of kidney disease.
• Increased amount of protein in the urine: 300 to 3000 milligrams per day. This indicates that you have severe kidney disease.
• Strongly increased amount of protein in the urine: more than 3000 milligrams per day. This indicates that you have severe to very severe kidney disease.

When the amount of protein in the urine is greatly increased, there is the nephrotic syndrome . The kidneys "leak" large amounts of protein, because the filter of the kidneys no longer works properly. Your blood is then not properly filtered and many proteins leak into the urine. 

Symptoms of protein in the urine

Protein in the urine usually does not cause any symptoms. Only when a lot of protein ends up in the urine, you can get the following symptoms: 

• Foamy urine. The protein makes your urine foam and can cause a clearly visible foam on the urine. The foam also remains on the urine. 
• Fluid buildup, such as swollen legs, ankles, and genitals. This is caused by the kidneys becoming confused by the loss of protein. As a result, they will retain more salt and water, resulting in moisture accumulation. 
• urinate less often. This is related to the fact that your body retains more water. 
• Reduced resistance. With the loss of (many) proteins, which are necessary for your immune system, your resistance deteriorates. 
• Thrombosis. If you lose a lot of protein through your urine, those proteins can do their job less well in inhibiting blood clotting. This increases the risk of blood clots and thrombosis.
• Increased risk of cardiovascular disease. Your liver tries to compensate for the protein loss through your urine and starts making more proteins. However, the liver also makes more fats and cholesterol, which increases the fat percentage in your blood. This increases the risk of arteries clogging. 

Do you notice these complaints and do you suspect that this is due to a lot of protein in your urine? Then contact your doctor immediately. With these symptoms, the amount of protein in the urine is already very high and there is possible the nephrotic syndrome.

Can you tell from your urine whether it contains proteins? 

It is not visible from your urine, except with foamy urine, whether it contains a high concentration of proteins. Blood in your urine, (white) flakes in your urine and cloudy urine generally do not indicate increased protein in your urine. Want to know more about what your urine can tell you? Read more about what the color of your urine says about your health here . 

Causes of protein in urine

An increased amount of protein in your urine is generally caused by a kidney problem. Well-functioning kidneys filter waste products from the blood. In this way they ensure that these waste products leave the body through the urine. If the kidneys do not work properly, you also pass out the substances that the body does need, such as proteins. Read more about the functioning of the kidneys and urinary tract here . 

Damage to the kidney filters can have various causes. It can indicate various kidney disorders. Read more about that below. Sometimes damage to the kidney filters, resulting in protein in the urine, occurs with the use of anti-inflammatory painkillers (NSAIDs), such as  diclofenac ,  naproxen  and  ibuprofen .

What can protein in your urine indicate?

Protein in the urine may indicate one of the following conditions: 

• high bloodpressure
• diabetes
• kidney inflammation such as glomerulonephritis
• nephrotic syndrome
• Wegener's disease
• Kahler's disease
• sarcoidosis
• urinary tract infection (including bladder infection and pelvic inflammatory disease )
• amyloidosis (buildup of proteins in kidneys, liver, and spleen)
• bladder cancer
• heart failure
• heavy metal poisoning
• preeclampsia

A greatly increased amount of protein in your urine can therefore indicate serious conditions. If you suspect that you are experiencing this, please contact your doctor. 

Protein in your urine and pregnancy

Are you pregnant and do you have a lot of protein in your urine? Then visit your doctor or midwife. This could indicate preeclampsia. With preeclampsia you have high blood pressure and proteins in your urine. Read more about preeclampsia here . 

Investigation and diagnosis of protein in urine

Your doctor or, in the case of very high protein levels in your urine, a nephrologist (kidney specialist) can examine you and make a diagnosis. This can be done, for example, by a test with a 'dipstick' or by a urinalysis. In some cases, a kidney biopsy is also needed. 

Testing protein in urine with a dipstick

The protein content of the urine can be tested with a dipstick. This is a rod that changes color as soon as it comes into contact with protein. In this test you collect urine with a jar and hold the dipstick in the urine for a few seconds. The protein content can then be read from the color change of the dipstick. You can have this test done at the doctor's office, but it is also possible to perform it at home. 

Testing protein in urine with urinalysis (microalbumin )

Also with a urinalysis, called a microalbumin, it is possible to examine proteins in your urine. Microalbumin measures the amount of albumin in your urine. This is generally measured by the albumin-creatinine ratio: the amount of albumin divided by the amount of creatinine (also called creatinine) in urine. 

Albumin is a protein that is made in your liver and is most abundant in your blood. When your kidneys are working properly, very little albumin leaks through to your urine. If your kidneys are not functioning properly, you will see this reflected in larger amounts of albumin in the urine. That is why we often look specifically at albumin in the urine to determine whether protein is leaking into your urine. Also, albumin is one of the first proteins to pass in your urine because it is so small. If you have more kidney damage, a lot of albumin will be visible in your urine. Larger proteins, the globulins, also end up in the urine. 

The amount of albumin is compared with the amount of creatinine in the urine in the microalbumin test. This says something about the dilution of your urine. If you have drunk a lot, your urine is more diluted. There is therefore less creatinine in your urine. If you have drunk little, your urine will be more concentrated and will contain more creatinine. Therefore, during a test for protein in your urine, the amount of albumin is compared with the amount of creatinine. In this way it becomes clear whether the protein values ​​in your urine are high, regardless of whether you drank a lot before the test or not. 

Preferably, morning urine is used in the microalbumin test. The albumin concentration in your pee is not constant. Exercise, a urinary tract infection, your blood pressure or fever can affect the result of the test, among other things. Morning urine is the most reliable. 

A kidney biopsy for protein in urine

In some cases, a kidney biopsy is needed to make the correct diagnosis if you have protein in your urine. During a kidney biopsy, a doctor uses a hollow needle to remove a piece of tissue from your kidney. This kidney tissue is then examined in a lab to establish the correct diagnosis for the kidney problem. 

Treatment of protein in the urine

The treatment of protein in urine often consists of medication. The medications you are prescribed depend on the underlying condition. Examples of medications you may receive include ACE inhibitors (such as Enalapril and Lisinopril) and A-2 blockers (such as Losartan or Valsartan). These lower blood pressure and have a positive effect on your kidneys. Often a water tablet (such as Hydrochlorothiazide or Furosemide) is also prescribed. In the case of more severe kidney diseases, Prednisolone and Cyclophosphamide can also be used in the treatment of protein loss through the urine. 

Can you prevent or lower the protein in your urine yourself?

It is difficult to completely avoid protein in your urine. It is often a symptom of kidney disease. That is why it is always important to determine the cause of the high protein content in your urine. However, you can have a positive influence on your kidneys through your diet and other lifestyle changes. We have listed a number of general tips and diet tips for you:

• Follow a low-salt diet. Do not add it to your meals and also pay attention to ready meals; these generally contain a lot of salt. If you have protein in your urine, the doctor usually prescribes that you are allowed 5 to 6 grams of salt per day. This is 2000 to 2400 milligrams of sodium per day. Not sure how much salt you are currently ingesting? Then use the handy Salt Meter from the Kidney Foundation .
• Drink 1.5 to 2 liters of water per day. Drinking enough water is good for the kidneys. 
• Drink less coffee and alcohol. Alcohol makes your kidneys work harder and the caffeine in coffee puts more pressure on your kidney filters. Both coffee and alcohol therefore put more strain on your kidneys. You also have to urinate more often. 
• Make sure you don't eat too much protein-rich food. Protein in your diet is healthy, but too much is not good. Too much protein creates too much pressure in your kidney filters, causing them to leak even more protein into your urine. Too high a protein intake can, for example, occur in people who exercise fanatically and consume a lot of protein powders and shakes.
• Move enough. This is at least 30 minutes of exercise a day at least 5 days a week.
• Maintain a healthy weight. If you are overweight, try to lose weight. Being overweight causes increased blood pressure in the kidneys. It is also important to do something about this if you are underweight. If you are very overweight, your body consumes your fat reserves and then the other tissues, including your kidneys.
• Do not smoke. Read tips to quit smoking here . 

Since protein in your urine usually indicates a kidney problem, you should always see your doctor if you suspect this. In addition to applying the above tips, it is good to keep an eye on the protein content in your urine and your blood pressure with your doctor.