Proteinuria

What is Proteinuria?

Proteinuria refers to the medical condition in which the urine of a patient has very high abnormal content of proteins.

This condition in most cases develops as the result of another underlying body condition that affects the functioning of the kidneys.

What are proteins?

Proteins refer to the body building blocks including the bones, hair, muscles and nails.

The proteins are also needed by our bodies for very important functions and purposes including the protection from infection, helping in blood coagulation as well as maintaining the circulation of the proper amounts of fluids in the body.

What happens so that a person can develop Proteinuria?

In the healthy person, as the blood passes through the kidneys, it is completely filtered of all the waste products which are then eliminated through urine while leaving the vital elements like proteins in the blood so that they can continue to circulate in the body and perform the already stated vital body functions.

Unless the kidneys are damaged, most proteins will be retained in the blood because they are generally big and they cannot pass through the filters of the kidney (glomeruli). However, the small sized proteins like the globulin and the albumin can pass through the filters of the kidney and so they can be found in the urine of the healthy person.

The function of albumin in the body is retaining of fluids in the blood.  It soaks up fluid from the tissues of the body. Proteinuria will thus arise when there is a problem of the filtration of blood such the large proteins pass through the glomeruli and they are thus eliminated in urine as waste.

Proteinuria in children

Children and teens may develop orthostatic proteinuria that does not necessarily signify problem of kidneys. This proteinuria in children develops because of the activities of the kid of standing for long hours during the day.

In most cases, benign orthostatic proteinuria in children does not need medication but the child should be put on the recommended diets that improve the functioning of kidneys like drinking a lot of water and taking a lot of fruits and vegetables.

What are the causes of Proteinuria?

There are various factors which acting singly or simultaneously may cause or aggravate the problem of proteinuria. Generally speaking, any condition that may lead to the inflammation of the kidney filters (glomeruli) can lead to development of proteinuria. In medical terms inflammation of the glomeruli is referred to as nephritis or glomerulonephritis.

These factors include

Infection of the kidneys/ Urinary tract: Infection of the kidneys is in most cases caused by bacteria, yeast, fungi or even virus.If proper medication for the infection is not sought as soon as possible, the glomeruli may become very inflamed leading to proteinuria.

Chemotherapy Side Effects: drugs like the Streptozocin can cause proteinuria even when they are taken as recommended. In the US, this drug is approved by the FDA for the treatment of metastatic pancreatic islet cells cancer. It has a very high toxicity risk in that it directs affects the pancreatic beta cells that produce insulin. Generally speaking, Streptozocin rarely cures the metastatic pancreatic islet cells cancer so it is only used in those patients whom the cancer cannot be treated by surgical procedures.

Some Biologic therapies: Some therapies like Interleukin-2 (IL-2) can lead to glomeruli problems leading to this problem. Interleukin-2 is approved in the FDA for use in treating Renal Cell Carcinoma that is metastatic. Note that Il-2 is not just a drug; it is a natural component of the body immunity system. It fights cancer by simulating growth of body immunity. The IL-2 drug side effects in the kidneys may lead to proteinuria.

Chronic diseases and conditions: The direct effects and symptoms of some chronic diseases or conditions may cause problems of the kidneys. The side effects of the medications that are used to treat these diseases and conditions may also cause serious side effects to the kidneys leading to proteinuria.

These diseases and conditions include:

High blood pressure: Elevated levels of blood pressure may interfere with the proper functioning of the kidneys. The kidneys may become inflamed and the end result will be development of proteinuria.

Diabetes: Diabetes refers to the condition in which the body is unable to regulate the levels of sugar in the blood.  Diabetic patients pass out urine that is especially very high in albumin. The elevated and unregulated levels of blood sugar may lead to severe proteinuria and kidney failure.

Multiple myeloma. This refers to certain cancer that affects the plasma cells. The plasma cells are a type of the body white cells. This condition can cause the presence of M-protein in urine.  The protein that presents in urine as a result of this condition is also referred to as Bence-jones protein or myeloma protein. Proteinuria associated with Bence- jones protein is called Bence- jones proteinuria.

System Lupus Erythematosus: this is a condition that occurs when the body immunity system for reasons that are not clearly known begins to attack the healthy body cells. This causes inflammation of various body organs among them the kidneys. Inflammation of the kidneys because of this condition (that is medically referred to as lupus nephritis) may cause proteinuria.

What is Orthostatic proteinuria?

Postural or orthostatic proteinuria refers to the increased urinary protein excretion during day time related to upright position and increased activity.

What is Tubular proteinuria?

Tubular proteinuria occurs due to the failure of re-absorption of low molecular weight proteins by proximal tubules.

What is Nephrotic range proteinuria ?

When more than 3- 3.5 mg of protein is excreted from the body in 24 hours, it is referred to as nephrotic proteinuria.

What is the latest news on the recent medical research on proteinuria?

The recent medical research tends to show that the type and level of proteinuria; that is, whether the proteins in the urine is albumin only or other proteins, strongly determines the kidney damage extent. It also determines whether the patient is at the risk of developing kidney failure that is progressive.

Recent research also tends to show that the people that suffer from this condition have an active cardiovascular disease or they are at risk of developing it in the future.  The damage of the blood vessels can lead to the failure of the heart, kidney failure or stroke.

A study that was conducted in 1996 under the sponsorship of the American National Institutes of Health (NIH) came to the conclusion that proteinuria is a precursor to the development of progressive kidney failure in those patients suffering from type II diabetes. In the view of these findings, the American Diabetes Association (ADA) and National Kidney Foundation (NKF) advise that all people suffering from type II diabetes should undertake very frequent proteinuria testing.

What is the medical advice for proteinuria patients?

Doctors advise that once you are diagnosed with proteinuria you should seek the proper advice and guidelines on what to do and what not to do so that you prevent any further development or complication of the proteinuria condition itself as well as the other underlying conditions that caused it.

Various health organizations also recommend that people that are at risk of the disease should have the levels of proteins in their urine checked very often.  Detection of the proteinuria condition early enough before it has progressed can help prevent kidney failure.

Who is at the risk of developing proteinuria?

People that are HYPERTENSIVE, DIABETIC or those who suffer from other chronic conditions that have damage to the kidneys are at very high risk of developing proteinuria. Diabetes is the leading cause of proteinuria in the US. Diabetes patients should be very vigilant and watch out for the early symptoms of the disease. Hypertension is the second leading cause of kidney failure that may lead to severe proteinuria.

Medical research shows that AFRICAN AMERICANS are higher risk (in fact about 20 times) of developing kidney problems that lead to proteinuria than the Native Americans.  The African Americans can develop proteinuria even when there blood pressure is not very much elevated or even when the blood sugar levels are not extremely unregulated.

Other people that are at high risk include:

• Overweight and obese
• The elderly people
• Hispanic problems
• American Indians
• Pacific Islander Americans
• The people that are related to people that  suffer from  kidney problems in general and proteinuria in particular

What are the symptoms of proteinuria?

Unless there has occurred damage to the kidneys, people with an active proteinuria condition may not present any proteinuria symptoms and they may not actually notice that they have any problem, of the kidneys.

When the proteinuria symptoms present, they are in most cases be accompanied by the symptoms of underlying conditions. If for example the proteinuria is caused by diabetes, it will be accompanied by diabetes symptoms like blurred vision, headache, fatigue, body weakness, frequent urination, thirst, hunger and such related diabetes symptoms. If the proteinuria is caused by high blood pressure (HBP), the patient may experience headache, dizziness, vertigo, sweating and such related HBP events.

At its advanced stages, proteinuria causes urine to appear foamy. Because of the excess removal of the proteins from the body, the patient may also begin to experience and show symptoms of swelling of the abdomen, hands, feet and face.

These proteinuria symptoms do not conclusively show that one is suffering from proteinuria. They may be experienced because of only the underlying disease or condition. Undertaking Urine or kidney function test is the surest way of confirming or ruling out proteinuria.

Effect of Proteinuria in pregnancy

Proteinuria in pregnancy causes a serious condition called proteinuria preeclampsia, where the pregnant woman becomes hypertensive, with associated symptoms like swelling of feet, hand and limbs.

Diagnosis of proteinuria

To confirm or rule out proteinuria, the doctor will need to conduct:

URINE TEST: This is the simplest test for proteinuria. The urine of the patient is collected and then placed in a container.  The tester will use paper that is chemically treated to perform the treat. It will change color if there is too much protein in urine.  More specific tests are required to find out the smaller amounts of proteins in the urine.

KIDNEY FUNCTION TEST: The doctor will check for the levels of urea nitrogen and Creatinine in the blood.  If the levels of these chemicals is very high then that indicates that the kidneys are not working properly or they have failed.  Healthy kidneys completely remove these chemicals and substances from blood. The doctor may also conduct an X-ray or ultra sound of the kidneys to ascertain the extent of damage.

What is the treatment for proteinuria?

Since proteinuria is a condition that develops as result of another condition or disease in the body, it is treated by controlling or treating that which is causing or aggravating it. The proteinuria treatment will thus involve the diagnosis of what is exactly causing the condition.

If the proteinuria is as a result of urinary tract infection (UTI), then the doctor may prescribe antibiotics if the UTI is caused by bacteria. If the cause of proteinuria is diabetes, the doctor may prescribe insulin injections or other oral diabetes medications.

The doctor may also prescribe medications for lowering blood pressure if the cause of proteinuria is elevated blood pressure. The proteinuria treatment thus depends on the underlying condition or disease.

What are the recommended proteinuria diets for patients?

All proteinuria patients are advised to strictly follow the RENAL DIET that is very low in protein, potassium, sodium and magnesium. In addition to this, they should also limit the intake of carbohydrates. Carbohydrates increase the levels of sugar in the blood and that may increase the diabetes complications. The carbohydrates are also in most cases converted in fats and so they may increase the proteinuria symptoms and complications.

The patients should avoid artificial sweeteners, caffeine, sugar and other sugary and sweet beverages and drinks. They should also avoid taking junk foods; this is to avoid the increase in weight and obesity that has been proven to increase the proteinuria risks and complications. The proteins should be taken in limited quantities.

The proteinuria patients are further advised to take lots of fruits and vegetables.  The fruits and vegetables are very rich in natural fiber and they help boost body immunity and the functioning of body organs. The patients should also limit or avoid the intake of the oils and the saturated fats.

References:

http://www.aafp.org/afp/20000915/1333.html

http://kidney.niddk.nih.gov/kudiseases/pubs/pdf/proteinuria.pdf