A test for protein in urine is used to diagnose many diseases. Protein in urine, or proteinuria, is a condition in which protein molecules are found in the urine. Normally they should not be there, or they may be present in trace amounts. The presence of residual protein in a urine test is normal.

Normally, in a healthy person, protein excretion in the urine does not exceed 8 mg/dL or 0.033 g/L per day.

In healthy people, protein in the urine should be absent or detected in extremely small quantities. Protein in the urine is diagnosed as proteinuria: this is a pathological phenomenon that requires consultation with a doctor and a number of additional examinations. Protein in the urine can appear for various reasons.

Protein in urine or so-called proteinuria, this is a condition when there are protein molecules in the urine that are absent normally in the urine or are found in very small quantities. Proteins are building materials that make up our entire body, including muscles, bones, internal organs, hair and even nails. Protein is also involved in a huge number of processes occurring in our body at the cellular and molecular level. An important function of proteins is to support oncotic pressure, thereby ensuring homeostasis in the body. In the renal glomeruli of a healthy person, a relatively small amount of low molecular weight plasma proteins is constantly filtered. There is usually no or very little protein in urine. Thus, protein in the urine is an undoubted sign that the function of the kidney filters - the so-called vascular glomeruli - is impaired.

Analysis on protein V urine designed to determine the amount contained V urine proteins such as albumin.

Protein in urine(proteinuria) - excretion of proteins in the urine exceeding normal (30-50 mg/day) values, usually a sign of kidney damage.

The normal result of a routine urine test is a urine protein level of 0 to 8 mg/dL. The normal daily urine test for protein is less than 150 mg in 24 hours.

Acceptable rate squirrel V urine during pregnancy, which doctors do not classify as symptoms of any threats - content squirrel up to 0.14 g/l.

Types of protein in urine (proteinuria)

There is a classification of proteinuria by degree depending on the amount of protein excreted in the urine in milligrams per day

• Microalbuminuria (30-150 mg)
• Mild proteinuria (150-500 mg)
• Moderate proteinuria (500-1000 mg)
• Severe proteinuria (1000-3000 mg)
• Jade (more than 3500 mg)

During the day, more protein is excreted in urine than at night. Protein can also be caused by vaginal discharge, menstrual blood, or sperm entering the urine.

Causes of protein in urine

Below are the most common causes of protein in the urine. Protein in the urine can be evidence of the following diseases:

• Multiple myeloma causes the appearance of a certain protein in the urine called M protein or myeloma protein.
• Systemic diseases: systemic lupus erythematosus (SLE) - can manifest as grosserulonephritis or lupus nephritis, Good-Pascher syndrome, etc.
• Diabetes. The protein found in urine in diabetes mellitus is albumin.
• Long-term high blood pressure (hypertension)
• Infections. Inflammatory processes in the kidneys
• Chemotherapy
• Tumors of the genitourinary system
• Poisoning
• Kidney injuries
• Long-term cooling
• burns

Determination of protein concentration in urine is a mandatory and important element of urine testing.

Symptoms when protein appears in urine

Proteinuria- the appearance of protein in the urine is a common, almost obligatory symptom of kidney or urinary tract damage. Sometimes proteinuria is accompanied by swelling, pus or blood in the urine, but most often proteinuria occurs without symptoms.

As a rule, microalbuminuria or mild proteinuria is not accompanied by clinical manifestations. Often there are no or mild symptoms. Below are some symptoms that are more common with long-standing proteinuria.

• Bone pain due to loss of large amounts of protein (more common with multiple myeloma)
• Fatigue as a consequence of anemia
• Dizziness, drowsiness as a result of increased calcium levels in the blood
• Nephropathy. May manifest as protein deposits in fingers and toes
• Change in urine color. Redness or darkening of urine due to the presence of blood cells. Acquiring a whitish tint due to the presence of a large amount of albumin.
• Chills and fever with inflammation
• Nausea and vomiting, loss of appetite

Determination of protein in urine

Protein in the urine and microalbuminuria are diagnosed by determining the protein in 24-hour urine (over a 24-hour period). Collecting urine for 24 hours can be very inconvenient for the patient, especially in everyday life. Thus, doctors resort to determining protein in a single portion of urine using electrophoresis.

A laboratory test to determine the amount of protein or albumin in the urine is especially recommended in people with kidney failure and diabetes.

If a urine test reveals an increased amount of protein, a repeat test should be performed after 1-2 weeks. If the second test confirms the presence of protein in the urine, then this confirms the presence of permanent proteinuria and the next step should be to determine kidney function.

Your doctor will recommend that you have a blood chemistry test to determine your levels of nitrogenous bases, namely urea and creatinine. These are waste products of the body that are normally eliminated by the kidneys, and if urea and creatinine in the blood are elevated, this indicates the presence of functional disorders in this organ.

How to treat protein in urine

If protein in the urine is a consequence of diabetes or hypertension, then it is certainly necessary to treat the underlying cause. In case of diabetes, your doctor will recommend you to follow a diet, and if the diet is unsuccessful, he will select the necessary drug therapy. With regard to hypertension, it is important to control blood pressure. There are a large number of drugs available on the pharmaceutical market for these diseases. Undoubtedly, the key to success is a correctly selected treatment regimen. It is important to control blood pressure levels no higher than 140/80.

It is also necessary to control the consumption of sugar, salt, and the amount of protein consumed.

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Protein in urine (proteinuria) is a condition of the body characterized by increased protein excretion in the urine.

Until 1997, the term albuminuria was synonymous with proteinuria.

After establishing the fact that not only proteins - albumins, but also globulins are excreted in the urine.

The term “albuminuria” has fallen out of widespread use as the definition of “protein in the urine.”

The extent of proteinuria (the amount of protein excreted in the urine) depends on three factors:

Fine almost all the protein is reabsorbed in the proximal tubules of the kidneys and only a small part of it excreted in urine. In case of violation any From the three mechanisms mentioned above, proteinuria of various genesis (origin) occurs.

At rest in a healthy person, when performing a general urine test, protein is not detected. In morning urine, the protein concentration also does not exceed 0.033 grams/liter.

0.033 grams/liter – minimum the concentration of protein in the urine, detected by standard laboratory tests during analysis. There is protein in the urine Always, and if its concentration does not exceed 0.033 grams/liter - we can say that the protein in the urine is “normal”, “absent”, “not detectable” or “not detectable”.

Proteinuria is the detection of protein in the urine in concentrations exceeding mark 0.033 grams/liter. Taking into account daily fluctuations in the excretion (excretion) of protein in the urine (the maximum amount occurs during the daytime), to assess the extent of proteinuria, a 24-hour urine analysis is performed, which makes it possible to determine daily proteinuria.

The appearance of protein in the urine is not always an alarming signal, but it can be a companion to serious diseases, including character.

A slight increase in protein in the urine of a healthy person may appear after prolonged physical activity. Proteinuria in a healthy person can also be observed after consuming foods rich in whole (undenatured) proteins (milk, raw egg); when the body is hypothermic (including after taking a cold shower); as a result of long walking; with emotional (nervous) stress; profuse sweating; due to allergic diseases.

The appearance of protein in the urine can also be a consequence of an increase in body temperature or an infectious disease.

Minor physiological (nutritional) proteinuria is observed in 92% of newborns in the first 3-7 days of life and is explained by excessive breastfeeding. This proteinuria, being short-term, does not require treatment; to eliminate it, in most cases, it is necessary to stop overfeeding the child.

Lasting loss minor volume of albumin protein (microalbuminuria) may not cause symptoms, but microalbuminuria increases the risk of developing coronary heart disease (myocardial infarction).

Pathological causes of an increase in the volume of protein in the urine may be infectious diseases of the urinary system (urethritis, cystitis), renal cell carcinoma.

The clinical and laboratory sign of kidney disease is precisely systematic detection of protein in the urine that cannot be explained by natural causes.

In the first days of life, in 92% of children, the level of protein in the urine exceeds normal values ​​due to an increase in the permeability of the epithelium of the glomeruli and tubules of the kidneys against the background of the hemodynamic characteristics of the newborn. This proteinuria in newborns is physiological. If elevated levels of protein in the urine persist after first week of life in infants, this proteinuria should almost always be considered as pathological.

A urine test for total protein (Urinalysis, Protein total) is used in the diagnosis of diseases of the urinary system of the human body, prescribed by a doctor to identify kidney diseases and control the treatment process.

A test for total protein in urine is prescribed by a doctor for the following diseases:

• IgA-glomerulonephritis;
• acute tubulointerstitial glomerulonephritis;
• focal segmental glomerular sclerosis;
• idiopathic membranous glomerulonephritis;
• lipoid nephrosis;
• other primary glomerulopathies;
• systemic connective tissue diseases (systemic lupus erythematosus, SLE);
• amyloidosis;
• kidney damage due to diabetes;
• preeclampsia;
• other multiorgan diseases with possible involvement of the kidneys;
• sickle cell anemia;
• malignant neoplasms of the gastrointestinal tract, lungs, blood.

In patients at risk of chronic renal failure (smoking, heredity, age over 50 years, obesity), a urine protein test is prescribed without fail. The analysis should also be carried out for symptoms of nephropathy (weight gain, microscopic hematuria, gross hematuria, etc. Indicator test strips are used for visual rapid diagnosis, measurement of protein concentration in urine, timely detection of albuminuria (proteinuria) both at home and in medical settings centers, clinical diagnostic laboratories, hospitals (clinics), medical institutions For independent urine analysis for protein and subsequent interpretation of the test result, special knowledge. not required.

The procedure for determining the extent of proteinuria is quite simple:

1. Remove the test strip from the pencil case (tube), after which it should be immediately sealed with a lid;
2. Immerse the test strip indicator in urine for 2-3 seconds;
3. After removing the test strip, remove excess urine by touching the edge of the strip to the container with the test sample;
4. Place the test strip on a flat, clean, dry surface so that the indicator element is at the top;
5. Within 60 seconds, the indicator element of the test strip is colored when protein is detected in the urine. Or doesn't change coloring if no traces of protein were found.

Instructions for using test strips from different manufacturers may differ in the recommendations and procedure for conducting the test. Detailed instructions for using certain products can be studied using the links below.

When performing a urine test yourself with test strips, it should be taken into account that sedimentary (if sediment is present) protein samples can be false positive if the test sample contains certain antibiotics, sulfonamides, or iodide contrast agents.

Test strips for determining protein in urine on the medical market today are represented by the following manufacturers:

• Analyticon Biotechnologies AG, Germany (“Analyticon”);
• Bayer, Germany (Stix series strips, as well as Microbumintest test tablets);
• Beijing Condor-Teco Mediacl Technology, China (ordered by Tespro, Ukraine, trademark “Samotest”);
• DAC-SpectroMed, Moldova;
• Dirui Industrial, China (“Uristik”);
• Erba, Czech Republic;
• IND Diagnostic Inc, Canada (“Multicheck”);
• HTI Medical, USA (“UrineRS”);
• Roche, Switzerland (“Micral-Test”);
• YD Diagnostics, Korea (“URiSCAN”);
• Biosensor AN, Russia (“Uribel”, “Uripolian”);
• Bioscan, Russia (“Bioscan”);
• Norma, Ukraine (“Protest”);
• Farmasco, Ukraine (“Citolab/Tsitolab”).

The portal contains descriptions of the following products for detecting proteinuria.

Single indicator strips (exclusively total protein in urine):

• Bioscan Belok (Bioscan Belok No. 50) Russian strips for analyzing urine for protein from Bioscan;
• Uribel (Uribel No. 50) test strips from the Russian company Biosensor AN.

Strips with two or more indicators:

• Albufan (Albufan No. 50, AlbuPhan) - indicator test strips for determining total protein and pH (acidity) of urine.

Strips with three or more indicators:

• Bioscan Penta (Bioscan Penta No. 50/No. 100) with five indicators from the Russian company Bioscan, allowing urine tests not only for total protein, but also for ketones, glucose (sugar), occult blood (red blood cells and hemoglobin), pH (acidity );
• Pentaphan / Pentaphan Laura for total protein, ketones, occult blood (red blood cells and hemoglobin), glucose and urine pH (acidity) from Erb Lachem, Czech Republic.

You can buy test strips for determining proteins (albumin) in urine at a pharmacy, pharmacy, using the drug booking service, among other things. Before purchasing test strips, you should check the expiration dates. You can order test strips at any available online pharmacy; they are sold with delivery, without a doctor’s prescription.

The price of test strips (in package No. 50, with a single indicator) usually does not exceed 150-200 rubles as of May 2017.

Self-diagnosis with test strips is not a substitute for regular assessment of your health status by a qualified medical specialist, doctor.

Treatment of proteinuria

Treatment of proteinuria (protein in the urine) comes down to restoring kidney function. If proteinuria is physiological in nature, its appearance is not associated with pathological causes - no treatment is required.

Treatment of protein in urine with remedies traditional medicine aimed at normalizing kidney function involves taking berries, decoctions, and tinctures.

The most common methods of treating proteinuria with folk remedies:

• Grind 20 grams of parsley seeds thoroughly, then pour in 200 milliliters of boiling water. The liquid is infused for 2 hours, used to treat proteinuria during the day in small portions;
• Squeeze the juice from the cranberries and cook the skins of the berries for 15 minutes. After cooling the broth, mix it with cranberry juice. Drink this fruit drink throughout the day;
• Pour 20 grams of chopped parsley root into 200 milliliters of boiling water. Allow the broth to brew for 90 minutes. Should be taken 30 milliliters 4 times a day;
• Pour 40 grams of birch buds with 200 milliliters of water, bring to a boil, then allow the broth to sit in a thermos for 90 minutes. Take 50 milliliters three times a day. When using this method of treating protein in the urine, the level of proteinuria should be constantly monitored. If protein in the urine decreases, stop treatment with this method;
• Pour boiling water over 350 grams of fir bark, seal the container with the tincture hermetically, and let it brew for 60 minutes. The tincture is taken 30 minutes before meals, 50 milliliters. When preparing the tincture, fir bark can be replaced with fir oil. 2-3 grams of oil are diluted in 60 milliliters of water. Admission rules are the same.

Before you begin treating proteinuria with traditional medicine, you should consult with a qualified medical specialist or doctor.

Denial of responsibility

The article about protein in the urine (proteinuria), diagnostic and preventive means, and treatment methods on the medical portal is a compilation of materials obtained from authoritative sources, a list of which is posted in the “Notes” section. Despite the fact that the reliability of the information presented in the article “ Protein in urine (proteinuria)» checked by qualified medical specialists, the contents of the article are for reference purposes only, is not guidance for independent(without contacting a qualified medical specialist, doctor) diagnostics, diagnosis, choice of means and methods of treatment.

- highly specialized glomerular cells, the main function of which is to provide glomerular filtration. Endocrinology(from the Greek ἔνδον - “inside”, κρίνω - “I highlight” and λόγος - “science, word”) - the science of the functions and structure of the endocrine glands (endocrine glands), the hormones (products) they produce, the ways of their formation and effects on the human body. Endocrinology also studies diseases caused by dysfunction of the endocrine glands and seeks ways to treat diseases associated with disorders of the endocrine system. The most common endocrine disease is diabetes mellitus.

Insulin– a protein hormone of peptide nature, formed in the beta cells of the islets of Langerhans of the pancreas. Insulin has a significant effect on metabolism in almost all tissues, while its main function is to reduce (maintain normal) the level of glucose (sugar) in the blood. Insulin increases the permeability of plasma membranes to glucose, activates key enzymes of glycolysis, stimulates the formation of glycogen from glucose in the liver and muscles, and enhances the synthesis of proteins and fats. In addition, insulin suppresses the activity of enzymes that break down fats and glycogen.

Exudate- a liquid released into tissues or body cavities from small blood vessels during inflammatory processes.

Preeclampsia– kidney pathology leading to dysfunction of the placenta. The consequence of gestosis is a decrease in the supply of oxygen and nutrients necessary for the fetus to live.

Coma, comatose state is a life-threatening condition between life and death, characterized by loss of consciousness, slowing or increasing heart rate, changes in vascular tone, impaired frequency and depth of breathing, extinction of reflexes until they disappear completely, impaired temperature regulation, a sharp weakening or absolute absence of reaction to any external irritation. The appearance of coma is preceded by loss of appetite, nausea (in some cases vomiting), headache, general malaise, constipation or diarrhea, and sometimes abdominal pain. If treatment is not started in a timely manner, the patient goes into a state of prostration (drowsiness, forgetfulness, indifference), his consciousness becomes darkened.

in vitro is a technology for studying a sample outside the body obtained from a living organism. Accordingly, when assessing the extent of proteinuria, urine (and the proteins, albumins, usually contained in it) is the test material obtained from the human body, and visual test strips for proteins are a diagnostic tool; the research itself is carried out in vitro. In English it is a synonym in vitro is the term “in glass”, which should be literally understood as “in a glass test tube”. In its general sense, in vitro is opposed to the term in vivo, meaning conducting research on a living organism (inside it).

Visual touch (indicator) disposable test strips, visual indicator test strips - pre-prepared laboratory reagents applied to a plastic or paper substrate. Not to be confused with electrochemical test strips for blood glucose meters.

Urology, urology (from the Greek οὖρον - “urine” and “λόγος” - “science, knowledge, study, word”) is a field of clinical medicine that studies etiology (origin), pathogenesis (course), and also develops methods of diagnosis, treatment and prevention diseases of the urinary system, diseases of the adrenal glands, the male reproductive system, and other pathological processes in the retroperitoneal space. Urology is a surgical discipline, a branch of surgery, and, unlike nephrology, deals with issues namely surgical treatment of the above organs and systems. The most common urological diseases are prostatitis, cystitis, urethritis, tuberculosis of the genitourinary system, prostate cancer, bladder cancer, kidney cancer, testicular tumors, usually accompanied by albuminuria (proteinuria). Emergency urology specializes in providing emergency medical care for the appearance of the following pathologies: acute

Hello, dear readers! Pathological processes that occur in the kidneys are primarily reflected in the composition of urine. Today I want to introduce you to another secret of laboratory research and tell you about increased protein in the urine, why it appears there, how much of it should be normal and what a deviation from the norm means.

This laboratory indicator is most important for the doctor to make a diagnosis. Normally, there should be no protein in the urine, but acceptable values ​​can be up to 0.033 g/l. Anything above this value is called proteinuria.

The biological value of proteins in the human body is extremely important. After all, proteins are building materials for building cells, protect the body from infections, help absorb vitamins and microelements, etc. Proteins - enzymes that make up enzymes help in biological and chemical processes in the body.

The kidneys filter our blood, removing from the body not only excess water, but also metabolic end products, inorganic and organic substances and toxins. The appearance of protein in the urine is one of the signs of a wide range of diseases that can be divided into three groups:

1. When the permeability of the glomerular filter is impaired, the renal glomeruli cannot filter high molecular weight proteins. Glomerular (glomerular) proteinuria is a mandatory sign of many kidney diseases, with hypertension, atherosclerotic nephrosclerosis, and congestive kidney.
2. Reabsorption disorder, when, during normal filtration in the glomeruli, reabsorption of low molecular weight proteins does not occur. Tubular proteinuria is observed in glomerulonephritis, diabetic nephropathy, renal amyloidosis, and systemic diseases.
3. Proteinuria “overflow” is much less common and most often it is one of the signs of neoplasms.

Protein in urine is normal

As I have already noted, a healthy person should not have protein in the urine, but its acceptable values ​​are up to 0.033 g/l.

Increased protein in the urine (also called albuminuria) can be orthostatic in nature and can be observed after heavy physical work, in athletes, with increased sweating, in weakly physically developed schoolchildren and adolescents, in pregnant women.

Exceeding the norm may be due to improper collection of urine for research. Even improper toileting of the genitals before taking the test can affect the result. How to properly prepare for a urine test?

Increased protein in urine

The cause of increased protein in the urine can be various different diseases:

• viral and bacterial infections,
• prolonged fasting and
• burn disease,
• hormonal changes.

As a rule, after recovery from these diseases, the release of protein into the urine stops.

The main and most common cause is pathological processes in the kidneys and urinary tract themselves.

But albuminuria is possible not only with kidney diseases. This can be one of the signs of allergic reactions, leukemia, epilepsy and heart failure.

Depending on the amount of protein, there are 3 degrees of proteinuria:

1. Initial – protein content in daily urine – 150-500 mg/l;
2. Moderate – from 500 mg/l to 2 g/l;
3. Macroproteinuria – more than 2 g/l, which occurs in severe kidney damage (glomerulonephritis, tuberculosis, tumors, amyloidosis, etc.). This level can lead to serious consequences, including kidney failure, when hemodialysis or an artificial kidney machine will be required to restore function.

If a slight increase in protein is observed for quite a long time, then this is also a reason for a more thorough examination by a doctor.

During pregnancy

As soon as a pregnant woman registers with the antenatal clinic, she needs to regularly, right up to the birth itself, have her urine tested before each visit to the gynecologist, including for protein. In the first half of pregnancy, urine is taken once a month, in the second half - once every 2 months. Why is this necessary?

Pregnancy is a special condition when, due to physiological characteristics, the functioning of some organs and the body as a whole changes. Thus, an increase in protein in the urine tells the gynecologist about possible pathologies that can negatively affect both the health of the woman herself and the growing fetus.

Exceeding normal protein levels may be due to physiological reasons (stress, use of certain medications, increased sweating, cold showers, etc.). Although experts say that a pregnant woman should not excrete more than 0.08 - 0.2 g/l per day. If exceeding the norm is observed once, then this does not cause concern. It is enough to regulate your diet and drinking regime. After eliminating the causes of protein in the urine, protein levels return to normal.

Pre-existing kidney disease, diabetes mellitus, and high blood pressure can provoke increased protein in pregnant women.

But the most dangerous condition during pregnancy, accompanied by excess of the norm, is gestosis. With gestosis, the placenta begins to function improperly, as a result of which the growing fetus does not receive enough oxygen and nutrients. A possible outcome is premature birth, arrest of fetal development and even death.

As a form of late toxicosis, a woman, combined with high blood pressure, can develop very life-threatening conditions: nephropathy, preeclampsia and eclamsia.

If during pregnancy you experience dizziness, headache, ringing in the ears, darkening of the eyes - these are serious symptoms that should never be ignored, you should immediately inform your gynecologist about the appearance of these symptoms.

In children

Normally, a healthy child should not have protein in his urine. But its appearance should alert both parents and doctors. Because this may be one of the symptoms of a serious pathology.

In young children, exceeding the indicators can occur not only due to reasons that are also typical for adults. This is possible due to overheating, when the child is dressed very warmly, elevated temperature, during excessive physical activity, even in infants, when they move their arms and legs very actively, when using certain medications, allergies, injuries and burns.

Orthostatic proteinuria may occur in adolescents. With increased physical activity, the protein level can reach 1.0 g/l, this is observed more often in teenage boys.

To be sure of the correctness of the analysis result, a portion of urine is collected after a thorough morning toilet and it is best to take the middle portion of urine.

In men

It is necessary to separately note the deviation from the norm in urine analysis in men. In addition to the reasons described above for the appearance of protein in the urine, its appearance can be provoked by excessive consumption of protein foods and proteins.

Elevated levels can tell the doctor about the presence of prostatitis and urethritis in men. With a thorough examination, protein can be observed not only in kidney pathology, but it can be a symptom of hemolytic anemia, myocardial infarction, obliterating atherosclerosis with gangrene of the extremities, oncology, muscle injuries.

Symptoms of increased protein in urine

If the indicators in the analysis do not slightly exceed the norm, then people do not make any special complaints. However, a significant and long-term deviation from the norm may be accompanied by the following symptoms:

• pain and aches in joints and muscles, night cramps in the legs,
• general weakness, loss of appetite, pale skin,
• fever and chills,
• high blood pressure,
• the appearance of edema,
• bad dream,
• loss of consciousness.

Visually, you can see flakes and white deposits in the urine, but the urine itself becomes cloudy.

If elevated protein is detected for the first time, it is necessary to retake the test, paying careful attention to the toilet of the genital organs, since remaining discharge in women or lubricant under the foreskin in men can get into the urine and the result will again be unreliable.

Dear readers, increased protein in the urine is a serious sign. If you have characteristic symptoms and changes in the appearance of urine, you must tell your doctor about this in order to begin timely treatment.

The presence of protein in the urine can be a signal of a malfunction in the body, since in a healthy person, during a urine test, it is absent or present in minimal quantities. How to decipher the analysis, and in what cases is it appropriate to use the expression “deviation from the norm”? Let's look further.

Protein levels in urine - what do they mean?

The indicators by which the presence of protein in urine is determined depend on how much protein in milligrams is excreted in the urine per day:

• Within 30-300 mg - indicate microalbuminuria, that is, the presence in the urine of one type of blood protein - albumin. This diagnosis may indicate earlier kidney damage or become a reason to suspect diabetes mellitus and hypertension;
• From 300 mg per dose to 1 gram per day – this is a mild degree of proteinuria. It occurs in patients with inflammatory processes in the urinary tract, chronic nephritis, and urolithiasis;
• From 1 gram to 3 grams of protein in urine per day – they talk about moderate proteinuria, which is diagnosed in acute tubular necrosis and hepatorenal syndrome;
• From 3 grams per day – this means the patient has severe proteinuria. This means that the patient's glomerular filtration barrier function in relation to protein size is impaired or the patient suffers from nephrotic syndrome.

The urine of a healthy person may contain small amounts of protein. These indicators usually do not exceed 0.033 g/l, and are considered normal for protein in the urine. Often such indicators are recorded as a complete absence of protein in the urine.

The normal levels do not differ depending on a person’s gender, which means that the normal level of protein in the urine of adult women and men is the same and amounts to up to 0.033 g/l.

Any deviations from the norm are a reason to undergo a full examination in order to exclude or prevent the risk of developing such serious diseases as diabetes, heart failure, nephrotic syndrome and kidney disease.

Causes of protein in urine

The following common causes of protein in the urine are considered:

• arterial hypertension at a progressive level;
• inflammatory or;
• mechanical damage to the kidneys;
• prolonged exposure to the cold;
• poisoning by toxins;
• high severity burns;
• cancer or tumor diseases of the kidneys.

You should not try to diagnose yourself. Only a qualified doctor can determine the exact cause of the appearance of protein in the urine.

Symptoms of increased protein in urine

As a rule, the presence of protein in urine does not have its own symptoms. You can even say that protein in the urine is a symptom that signals a malfunction of an organ such as the kidneys. Proteinuria can only manifest itself with a concomitant disease or with a pathological condition.

But, proteinuria may be accompanied by symptoms that indicate problems with the kidneys. These symptoms include:

• Painful sensations in the hands;
• Anemia (see also – ?);
• Fatigue and decreased performance;
• Edema;
• Chills and high fever;
• Decreased appetite;
• Nausea and vomiting;
• Change in urine color;
• Drowsiness ().

Finding one of the above symptoms should be a reason to consult a doctor and give all the necessary tests, including a urine test.

Protein in a child's urine

Young children, as I rule, if there are no other indications for this test, donate urine during the vaccination period twice a year. The results of the analysis are interpreted as follows:

• Normal indicators can be considered if the level of protein in the urine does not exceed 0.036 g/l;
• When this indicator increases to 1 g/l per day, we can already talk about moderate proteinuria;
• When a urine test shows a protein level of 3 g/l or higher, this is severe proteinuria, which means the development of some kind of kidney or urinary tract disease.

When children have high levels of protein in their urine, there may be a decrease in the level of this substance in the blood, which leads to high blood pressure and edema. In such cases, you should not postpone consultation with a specialist.

Protein in urine in pregnant women

There are often cases when protein is found in urine in women who are expecting the birth of a baby. The causes of this phenomenon can be temporary (external factors) or permanent (inflammatory processes).

The main reasons for the appearance of protein in the urine of women during pregnancy include:

Changes in hormonal levels;

Kidney diseases;

Pressure of the uterus on the kidneys;

Preeclampsia.

In later stages of pregnancy, the pressure of the uterus on the kidneys can cause protein content in urine. This is a normal physiological process, but in order to exclude more serious pathologies and kidney diseases, the indicators cannot be ignored; you still need to establish the exact cause and undergo an examination.

But gestosis can cause dysfunction of the placenta, which will lead to the fact that the fetus in the womb will not be able to receive enough food and oxygen for full development. This condition is dangerous because it does not manifest itself outwardly, that is, a pregnant woman may not even be aware of the presence of this problem.

It is important to understand that during pregnancy, all test readings can change every day. Thus, it is possible to determine that protein in the urine of pregnant women indicates the development of pathology only after a complete examination.

Often, by the time of birth, the protein in the urine is completely gone, and the mother meets her baby in this world completely healthy and strong.

How to take a urine test correctly?

Its reliability depends on how urine is collected for analysis. Only urine collected in the morning, and on an empty stomach, will be suitable for analysis.

For analysis, you need to prepare a container for urine - a special jar with a wide neck. It can be bought at a pharmacy. But, even if the container was purchased at a pharmacy, it must be thoroughly washed and dried before analysis.

If a urine test is required for an infant, a special urine bag can be used as a container for urine. Such bags are put on the child’s genitals under a diaper.

You cannot use the contents of unscrewed diapers for urine analysis, as this will not bring a reliable result.

The genitals of both adults and children must be clean. Therefore, before urinating, you should wash yourself using soap.

All these procedures are done in the morning, immediately after waking up. The day before, it is not recommended to eat fried foods, as well as foods that contain a lot of protein.

Treatment of increased protein in urine

Only by establishing the exact cause of proteinuria can effective treatment be selected. For example, if a patient is diagnosed with diabetes, he is prescribed a special diet. If you do not follow this diet, your blood protein levels will either remain the same or increase, which can lead to serious kidney problems.

The doctor prescribes individual treatment, which depends on the stage of a particular disease, how it progresses and what is caused.

It is impossible to find treatment options on your own, but you can take some measures to reduce protein levels in your urine. Such measures include folk methods to reduce the level of protein in urine.

Cranberry juice

Squeeze the juice out of a handful of cranberries and cook the skins of the berries for 15-20 minutes. Wait until the resulting broth has cooled and add berry juice to it. For sweetness you can add 1 tsp. honey or granulated sugar. Drink fruit juice a few minutes before breakfast.

Parsley seed infusion

20 grams of parsley seeds should be crushed and poured with a glass of boiling water. This drink is infused for 2 hours, after which it must be drunk throughout the day, dividing the entire volume received into several doses.

Birch buds

Pour 2 tablespoons of birch buds into a glass of plain water and bring to a boil. While the broth is hot, pour it into a thermos and leave for an hour and a half. When the decoction is infused, it should be taken 3 times a day, 50 grams.

Fir bark tincture

The third part of a 1 liter jar should be filled with fir bark. Fill the rest of the jar with boiling water. This medicine should be infused only in a water bath for 1 hour. You need to take 50 grams of infusion half an hour before each meal.

Decoctions for prevention

It is also appropriate to take various herbal tinctures as preventive measures. The most suitable are decoctions made from corn, oats, pumpkin seeds and golden mustache leaves.

The term “proteinuria” refers to the appearance of any type of protein in the urine in quantities exceeding physiological (normal) values.

Detection of an increased level of protein in the urine is the most studied and significant pathological symptom in the practice of a doctor, indicating a malfunction of the urinary system.

The severity of proteinuria can vary significantly between patients, depending on the underlying disease. In addition, the detection of protein in the urine can be observed in isolation or in combination with other changes in the TAM (hematuria, leukocyturia, bacteriuria).

History of the discovery of the syndrome

The first information about changes in the chemical composition of urine in certain diseases was obtained back in the 17th century. Thus, in 1694, the outstanding Leiden physician F. Dekker first discovered protein in the urine of patients with proven kidney pathology.

In his research, he was able to demonstrate that urine contains a substance that coagulates and coagulates when heated, which in turn leads to the formation of "turbidity."

Based on the experiments carried out, F. Dekker proposed specific methods for detecting this impurity using acetic acid.

As a pathological syndrome, proteinuria was described by D. Cotugno in 1764, identifying it in a patient with acute pyelonephritis. Proteinuria and renal pathology are finally associated with R. Bright.

To identify the protein, he used a fairly simple and specific technique - heating a small amount of urine in a spoon over a flame (the protein precipitated after denaturation). In a number of experiments, nitric acid was used to detect proteins.

R. Bright reliably established the connection between proteinuria and chronic nephritis, which for some time received the name “Bright’s disease.”

2. Boundaries of normality and pathology

Often, when asked about the presence of protein in the urine of healthy individuals, an ambiguous answer can be obtained. What is considered the normal range for diagnosing pathological proteinuria? There are quite contradictory data in the medical literature.

With the protein concentration in a single portion of urine, everything is quite simple; normally it should not exceed 0.03 g/l (in children under one year old up to 0.002 g/l, in children over one year old - 0.036 g/l).

The level of daily protein loss in urine should normally not exceed 0.15 g/day (up to 100 mg/day Pushkarev I.A. 1985; 150 mg/day Bergstein J., 1999; 200 mg/day B.M. Brenner, 2007) .

At the same time, the calculated concentrations of the level of daily proteinuria based on the given norms in a healthy person (taking into account diuresis of up to 1.5 l/day) show the possibility of excreting up to 0.1 grams of protein.

Such discrepancies are explained by individual and racial characteristics of protein excretion in the urine.

The vast majority of people have mild proteinuria (about 40-50 mg per day). In 10-15% of the population, daily urinary protein excretion reaches 0.150 g/day without confirmation of urinary system pathology.

The chosen diagnostic method is of great importance in assessing the degree of daily protein loss in urine.

By generally accepted methods, such as the sulfosalicylic acid test or the biuret reaction, protein is not detected in the urine of a healthy population. Patients who detect a one-time increase in protein levels in the urine are often prescribed.

3. Protein composition of urine

To assess proteinuria correctly, you need to have an idea of ​​the qualitative and quantitative composition of normal urine.

In a portion of the urine of a healthy person, up to 200 different proteins can be identified, filtered from the blood or secreted by epithelial cells of the urinary system.

Approximately 50-70% of urine protein is uroromucoid (uromodulin) - a product of renal tissue synthesis. In the lumen of the renal tubules, uromodulin forms a specific gel-like structure, impermeable to water, but permeable to ions.

Uromodulin is detected in kidney tissue from the 16th day of embryogenesis. In daily urine it is detected in the amount of 20 - 100 mg, and its synthesis increases with high salt intake and taking loop diuretics (furasemide, torsemide).

The appearance of tissue proteins may be the result of normal renal excretion and constant renewal of kidney tissue.

Plasma proteins are the second in terms of specific gravity.. When using high-quality diagnostic systems, about 30 plasma proteins can be detected in urine, the leading position among which is albumin.

Proteins from tissues of the heart, pancreas, liver, and transplant antigens can be detected in urine. Damage to heart tissue in patients is accompanied by myoglobinuria, and some tumors lead to increased excretion of low molecular weight proteins.

Almost all known human hormones are excreted in the urine. In pregnant women, proteins secreted by placental tissue can be detected in the urine.

4. The mechanism of appearance of protein in urine

Urine formation occurs in the main structural element of the kidney - the renal glomerulus (a network of arterial capillaries enclosed in a capsule).

Blood entering the glomerular capillaries is filtered through a special glomerular membrane to form primary urine. The glomerular filtration membrane has a rather complex structure and includes:

1. 1 The inner layer is represented by endothelium, most of which is covered with pores with a diameter of 40 nm. The pores are covered by a diaphragm, so protein filtration at this stage is determined by both the size of the pores and the condition of this diaphragm;
2. 2 A three-layer membrane (basal), located outside the inner layer. Its permeability to protein molecules is determined by its electrical charge and the arrangement of collagen filaments;
3. 3 Epithelial lining (podocytic apparatus), located on the urinary side of the basement membrane. This layer is responsible for the active filtration process using microfilaments.

In a healthy person, the glomerular filter can pass proteins of a certain size (no more than 4 nm, weighing no more than 70 kDa). Proteins such as serum albumin, myoglobin, prealbumins, lysozyme, microglobulins, etc. are freely filtered.

In addition to size, the charge of the protein molecule plays an important role in the filtration process. The basement membrane is normally negatively charged and does not allow active filtration of plasma proteins that have the same charge.

Figure 1 - Structure of the nephron

If small plasma proteins manage to pass the renal filter, they are almost completely absorbed in the renal tubules.

Summarizing the above, physiological protein excretion is the result of the interaction of the glomerular and tubular mechanisms, and damage to either part of the nephron can lead to proteinuria.

Detection of transient or permanent proteinuria in a person requires a thorough examination. Next, let's move on to studying the main reasons for the increase in protein levels in the urine.

5. Functional proteinuria

Functional proteinuria is not associated with damage to renal tissue. It is based on a transient disturbance of protein filtration. This condition can occur when:

1. 1 Severe psycho-emotional stress;
2. 2 Eating large amounts of protein;
3. 3 Dehydration, electrolyte disturbances;
4. 4 Chronic heart failure, hypertension;
5. 5 Fever;
6. 6 Against the background of exhausting physical exercise (marching proteinuria);
7. 7 Against the background of hypothermia.

In infants, dehydration proteinuria often occurs, which is based on feeding disturbances, toxicosis, diarrhea, and vomiting. After removal of the provoking factor, such proteinuria stops.

In adolescents, so-called orthostatic proteinuria can be detected - increased protein excretion in the urine when moving to a standing position. Children predisposed to orthostatic proteinuria are diagnosed with active growth, low muscle mass, kyphosis, lumbar lordosis, low blood pressure and absolutely normal kidney function.

Proteinuria occurs when a teenager stands. Lordosis of the spine leads to the fact that the anterior surface of the liver moves down and somewhat presses the inferior vena cava. Stagnation of blood in the renal veins provokes the release of protein in the urine.

In physiological proteinuria, the largest proportion is made up of low-molecular-mass proteins (up to 20 kDa), for example, Ig, 40% are high-mass proteins (65 kDa), 40% are uromodulin.

6. Pathological proteinuria

Pathological proteinuria develops when the renal glomeruli, where filtration occurs, or the renal tubules, where reabsorption of protein molecules occurs, is damaged.

Depending on the level of damage, three types of pathological proteinuria can be distinguished:

1. 1 Prerenal, or overload, associated with increased protein breakdown and the appearance of increased concentrations of low molecular weight proteins in the blood plasma.
2. 2 Renal, associated with damage to the filtration apparatus of the renal glomerulus and/or renal tubules, where reabsorption of protein molecules occurs.
3. 3 Postrenal, caused by pathology of the underlying urinary tract. Most often caused by inflammatory exudation.

6.1.

The basis of prerenal proteinuria is the appearance in the patient's blood plasma of proteins with a small molecule size, which can pass through a healthy kidney filter and enter the urine in large quantities.

The appearance of such proteins in the plasma is associated either with their increased synthesis or with the breakdown of tissue structures and cells. This condition can occur when:

1. 1 Plasmablastic leukemia;
2. 2 Multiple myeloma;
3. 3 Connective tissue diseases;
4. 4 Rhabdomyolysis;
5. 5 Lymphoma with paraproteinemia;
6. 6 Hemolytic anemia;
7. 7 Macroglobulinemia.

Most often, this type of proteinuria is caused by an increase in the blood of Ig light chains (Bence Jones protein), myoglobin, hemoglobin, and lysozyme.

Congestive forms of prerenal proteinuria are possible, which occur with decompensated heart disease, metastases, and abdominal tumors.

Neurogenic prerenal proteinuria can be classified as a separate category, which can be provoked by an epileptic seizure, traumatic brain injury, hemorrhage, or vegetative crisis.

6.2.

Renal In this case, an increase in protein levels in the urine is associated with damage to the renal parenchyma or renal interstitium.

1. This is typical for the following conditions:
2. 1 Glomerulonephritis (acute or chronic);
3. 2 Nephropathy in diabetes;
4. 3 Nephropathy of pregnancy;
5. 4 Amyloidosis;
6. 5 Kidney tumors;
7. 6 Hypertensive nephrosclerosis;

7 Gout.

1. Depending on the location of the damage, the composition and volume of proteins excreted in the urine changes, which makes it possible to distinguish:
2. 1 Renal glomerular (glomerular) proteinuria, which develops when the renal cortex, in which the nephrons are located, is damaged.

2 Renal tubular proteinuria, which develops against the background of problems with the reabsorption of proteins in the proximal tubules.

6.2.1.

1. Damage to the renal glomeruli
2. When the renal glomeruli are damaged, changes of the glomerular type are recorded in the urine:

1 With the loss of the negative charge of the basement membrane, low molecular weight protein molecules (albumin and transferrin) begin to predominate in the urine.

2 If the integrity of the pores in the membranes is damaged, large-molecular compounds (immunoglobulin G) are detected in the urine.

1. Thus, the nature of damage to the renal filter affects the ability to pass protein molecules of different sizes and masses.
2. That is why, according to the composition of uroproteins, proteinuria is distinguished:
3. 3 Non-selective - isolation of protein with a mass from 830 to 930 kDa.

To determine the degree of selectivity, a special index is used, which is the ratio of the isolation of proteins with high mass to low molecular weight (usually the IgG/albumin ratio).

A ratio of up to 0.1 (selective) indicates a filtration defect associated with a violation of the ability to retain negatively charged molecules. An increase in the index of more than 0.1 indicates non-selectivity and permeability of the filter pores for macromolecules.

Determining the degree of selectivity of glomerular proteinuria is important for developing patient management tactics.

The selective nature of protein loss in the urine indicates minimal damage, so the effectiveness of glucocorticosteroids is high in such patients.

Non-selectivity is associated with more severe changes in the renal filter (membranous nephropathy, glomerulosclerosis, proliferative glomerulonephritis); in treatment, as a rule, resistance to steroids is observed.

Increased hydrostatic pressure in the glomeruli can also lead to increased protein filtration, which is a variant of glomerular proteinuria.

6.2.2.

Tubular protein loss

It develops against the background of impaired reabsorption of proteins in the renal tubules and is manifested by the release of low molecular weight proteins (weight below 40 kDa), which are normally completely reabsorbed.

Tubular proteinuria, as a rule, does not exceed 2 g/1.73 mx2/day.

1. Pathologies accompanied by tubular protein loss include:
2. 1 Interstitial nephritis;
3. 2 Urinary infections;
4. 3 Urolithiasis;
5. 4 Toxic effects;
6. 5 Wilson's disease;

6 Fanconi syndrome.

Indicators of tubular proteinuria are B2-microglobulin, retinol-binding protein and/or alpha1-microglobulin.

The level of excretion of B2-microglobulin has the greatest diagnostic value. An increase in the level of albumin in the urine with a normal content of B2-microglobulin indicates damage to the glomeruli, while the predominance of B2-microglobulin indicates tubular pathology. At the same time, we should not forget about the possibility of erroneous analysis results.

6.3. Postrenal

1. Postrenal proteinuria is caused by the release of inflammatory exudate rich in protein into the urine and is associated with damage to the underlying parts of the urinary tract.
2. This condition can occur when:
3. 1 Inflammatory pathology of the urinary tract (cystitis, urethritis, prostatitis);
4. 2 Bleeding from the urinary tract;

Fig 1 - Differential diagnosis of proteinuria. Source -V.L. Emanuel. Problems of pathology of the urogenital system // Journal of laboratory medicine. No. 7, 2015.

7. Gradations of proteinuria

Based on the amount of protein excretion, it is advisable to distinguish between the variability of proteinuria, which ranges from microproteinuria to a high, nephrotic degree (above 3 g/day).

The term MAU (microalbuminuria) refers to the excretion of albumin in the urine in an amount above the physiological norm, but below the sensitivity of standard test systems.

It is customary to talk about UIA when the daily loss is from 10 mg to 300 mg of albumin. MAU may be the only early sign of glomerular damage, for example, in diabetic nephropathy.

MAU appears long before the decline in GFR (glomerular filtration rate) begins. Microalbuminuria also occurs in hypertension and kidney transplant rejection.

Low grade proteinuria (300 mg -1 g/day) can be detected in acute urinary tract infections, urinary tract obstruction, urolithiasis, and nonspecific nephritis.

Moderate loss of proteins (1 g - 3 g/s) develops with acute tubular necrosis, glomerulonephritis, hepatorenal syndrome, amyloidosis.

A large loss of protein in the urine (more than 3 g/s) is almost always associated with a disruption of the glomerular filter and a change in the “size-charge ratio” of proteins and membranes.

8. Clinical manifestations

Proteinuria, which occurs in a mild form, usually does not have any clinical manifestations or is masked by the symptoms of the underlying pathology.

With a significant increase in the concentration of protein in the urine, foaming occurs during urination. This “foam” lasts quite a long time.

Constant and significant loss of proteins in the urine can lead to the development of edema of the face, limbs, and abdomen.

9. Kidney failure

Proteinuria is one of the most significant risk factors for the formation and progression of CKD (chronic kidney disease). A relationship has been proven between the increase in protein loss in the urine and the rate of decline in kidney function.

In one of the latest meta-analyses (Stoycheff, 2011), the role of proteinuria as an independent risk factor for CKD progression was once again proven.

Proteinuria (including MAU) are risk factors for the development of complications from the cardiovascular system.

International expert recommendations use a normogram to determine the risk of an unfavorable prognosis for the development of CKD and renal failure (Figure 2). The higher the level of proteinuria, the higher the risk of fatal outcomes.

Fig 2. - Risk nomogram for unfavorable prognosis KDIGO-2012, 2013: green – low risk (if there are no other markers of renal pathology or the pathology itself), yellow – moderate risk, orange – high risk, red – very high risk

10. Treatment tactics

The tactics for managing a patient with proteinuria directly depend on the cause, the risk of an unfavorable outcome, and the prognosis, which determines the need for dynamic monitoring by a therapist or nephrologist.