The specific gravity of urine is reduced in adults. Conducting urine specific gravity analysis. How to normalize the specific gravity of urine

A general urine test is done in order to understand how a person’s internal organs work, whether they fully cope with their functions, and whether there is a hidden pathology in the body that may not manifest itself externally.

There are certain standards that the urine being tested must meet. Deviation from them indicates one or another deviation, which requires further diagnosis and, possibly, immediate treatment.

One of the parameters that is paid attention to during a general study is the specific gravity of urine. A person's kidneys can eliminate waste products regardless of how much fluid enters the body.

If there is not enough of it, the kidneys begin to economize and excrete the necessary particles with urine in a small volume - in this case, it turns out to be concentrated, and its specific gravity is quite large. If there is too much liquid, the volume of urine, on the contrary, increases, and the density and concentration decrease.

Specific gravity, also called density, is a parameter that shows the ability of the kidneys to concentrate and dilute urine.

Normal indicators

The normal specific gravity of urine in women and men who are healthy usually fluctuates between two numbers - 1,010 (the lowest threshold) and 1,028 (the highest threshold). A figure within this range is considered normal.

Indicators can change during the day, and differ at different times, because they are influenced by:

• A person eats food at different times - as a rule, food is usually eaten in larger quantities for breakfast compared to dinner;
• Loss of fluid through sweat, especially in the summer;
• The amount of air exhaled.

In order for the final figure to be adequate and as close to reality as possible, it is recommended to take morning urine, preferably on an empty stomach.

Phenomena when the specific gravity of urine is low, or vice versa, is too high, require diagnosis and additional tests.

Depending on the result, the following conditions are distinguished:

• Hyposthenuria - when the specific gravity reaches 1.010 and below;
• Isosthenuria - indicators equal to 1.010;
• Hypersthenuria - the final figure is more than 1,010.

Density is a parameter that tends to vary greatly depending on the time of day. Therefore, a final conclusion cannot be reached on the basis of a general analysis alone - an additional study according to Zimnitsky will be required, during which the density of urine is measured from its portions collected at different hours.

The normal specific gravity of urine in children depends on age - for a one-year-old baby it ranges between 1.002 - 1.030, and for a ten-year-old child between 1.011 - 1.025.

If the density is increased

This occurs due to protein and glucose. When the specific gravity of urine is elevated, this may indicate:

• Diabetes mellitus. This disease can be suspected on the basis of one general analysis if the final density indicator reaches 1,030. In some cases, it can reach 1,040 or even 1,050;
• Nephrotic syndrome, glomerulonephritis;
• Taking certain medications;
• Intravenous infusion of drugs such as dextran or mannitol;
• Lack of fluid in the body, or water imbalance;
• Severe dehydration, which can be caused by vomiting due to poisoning or intestinal infection, diabetes, prolonged exposure to the sun or in a sauna;
• Toxicosis (in pregnant women);
• Oliguria - a decrease in the amount of urine produced by the kidneys;
• Heart failure and other diseases that are accompanied by edema;
• Liver diseases.

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The kidneys are a paired organ with a fine structure, so the slightest change in the normal course of any internal processes leads to noticeable deviations in the performance of the urinary system.

Pathologies of the kidneys, urinary tract and some other organs can be determined by a general urine test (abbreviated to OAM on medical forms). It is also called clinical.

Why is this test prescribed?

Urine is a biological fluid in which the final waste products of the body are released from the human body.

It is conventionally divided into primary (formed by filtration in the glomeruli from blood plasma) and secondary (formed by reabsorption of water, necessary metabolites and other solutes in the renal tubules).

Disruption of this system entails characteristic changes in normal TAM indicators. Thus, the analysis can show:

1. 1 Deviations in metabolism;
2. 2 Signs of urinary tract infection;
3. 3 Effectiveness of treatment and diet;
4. 4 Dynamics of recovery.

A person can contact a laboratory for a urine test on his own initiative if he notices sudden changes in his physical characteristics. But more often the patient receives a referral from a specialist at the clinic, who then deciphers the results obtained.

OAM is included in the list of basic studies during preventive examinations of the population, clinical examination, it is prescribed when seeking medical help from a specialist, during pregnancy, during hospitalization and in some other cases.

A general urine test consists of a sequential study of:

1. 1 Physical characteristics of the sample;
2. 2 Chemical composition;
3. 3 Microscopic examination of sediment.

2. Patient preparation

Before submitting the material for general (clinical) analysis, consult your doctor about the possible temporary cessation of taking certain pharmaceutical drugs. For example, diuretics should be stopped 48 hours before sample collection.

Women should remember that menstruation usually skews the results. For testing, it is better to choose a time before your period or two days after the end of the discharge.

The day before collecting biomaterial, avoid foods with a high content of pigments, alcohol, fatty, smoked foods, sex, and excessive physical and psycho-emotional stress. All this can distort the OAM results.

For analysis, a morning urine sample is collected, optimally its middle part. Before collection, the patient must toilet the external genitalia (bath, shower, wet wipes).

After the start of urination, it is better to flush the first portion into the toilet, collect the middle portion in a clean, sterile container (optimally in a sterile pharmaceutical container). The minimum volume of urine required for testing is 50 ml. There is a mark on the medicine cup to the level at which it is advisable to fill the container.

In young children, it is often difficult to collect urine for analysis. Therefore, when collecting, you can use small tricks:

1. 1 Buy special soft polyethylene containers with a sticky edge at the pharmacy. Not all children like this procedure, but for some it is acceptable.
2. 2 Before picking up, take the baby to the bathroom and turn on the water. A child up to one year old can be breastfed beforehand, and an older baby can be given water to drink. Urination in babies is tied to feeding, so the task can be made easier.
3. 3 Some children pee several times with intervals between peeings of 10-15 minutes. To collect material from such babies, it is better to prepare several containers so that you can collect the droplets in different dishes without staining them during manipulation.
4. 4 Before the procedure, you can do a soft, stroking massage in the lower abdomen, in the bladder area.

3. What should not be done when collecting urine?

When collecting material for clinical urine analysis, it is not recommended:

1. 1 Use untreated dishes, the contents of a potty, a diaper, a diaper, a plastic bag. This analysis is called “dirty”; it is not suitable for assessing the condition of the urinary system.
2. 2 Use for analysis stale urine that has stood for more than 3 hours or has been in the refrigerator without a special preservative.
3. 3 Collect material for OAM after defecation, during menstruation or after sexual intercourse.
4. 4 Collect material for research during acute inflammatory diseases of the reproductive system, skin around the urethra and vagina (you must warn the doctor about this in advance). It will not be possible to collect such an analysis purely.
5. 5 Do not use a urinary catheter unless there is an urgent need for it (prostate cancer, prostate adenoma, a bedridden seriously ill patient and other situations that are specified by the attending physician). When placing a catheter at home, there is a high risk of secondary infection.

The table below presents the main indicators, their standards and interpretation. Clinical urine analysis in women is practically no different from that in men, with the exception of some parameters. These small nuances are noted in the table.

4. Physical properties

4.1. Quantity

When assessing the total amount of urine excreted, it is necessary to take into account the possible dietary characteristics of each patient. In an adult who follows a normal diet, daily diuresis ranges from 800 to 1500 ml.

Diuresis directly depends on the volume of fluid drunk. Typically, 60-80% of what you consume per day is eliminated from the body. The normal ratio of daytime to nighttime diuresis is 3:1 or 4:1.

A condition characterized by increased urine output (more than 2000 ml per day) is called polyuria.

A similar phenomenon is observed normally:

1. 1 If you have drunk a lot over the past day;
2. 2 With nervous excitement or overstrain.

Polyuria can be observed in the following pathological conditions:

1. 1 Kidney diseases (CKD, stage of resolution of acute renal failure);
2. 2 Relief of edema, for example, against the background of diuretics;
3. 3 Diabetes insipidus and diabetes mellitus;
4. 4 Nephropathies (amyloidosis, myeloma, sarcoidosis);
5. 5 Taking certain medications.

The reverse condition is called oliguria. With oliguria, less than 500 ml of urine is excreted per day.

Physiologically it can occur with:

1. 1 Reduce fluid intake;
2. 2 Loss of fluid through sweat in the heat;
3. 3 Significant physical activity.

It is noted in the following pathologies:

1. 1 Cardiac decompensation;
2. 2 Poisonings;
3. 3 Excessive loss of water from the body (for example, during profuse diarrhea, vomiting);
4. 4 Burns;
5. 5 Shock conditions;
6. 6 Fever of any origin;
7. 7 Kidney damage of infectious, autoimmune and toxic origin.

Anuria is a condition in which urine production stops completely.. Anuria is typical for:

1. 1 Initial stage of acute renal failure;
2. 2 Acute blood loss;
3. 3 Uncontrollable vomiting;
4. 4 Stones in the urinary tract with obstruction of the lumen;
5. 5 Oncological diseases accompanied by obstruction and compression of the ureters.

Nocturia is a condition in which nocturnal diuresis significantly predominates over daytime. Nocturia is typical for:

1. 1 Diabetes insipidus and diabetes mellitus;
2. 2 Many kidney diseases;

4.2. Urinary frequency

In addition to the daily amount of urine, pay attention to the frequency of urination. Normally, this process is performed by a person 4-5 times during the day.

Pollakiuria is characterized by frequent trips to the toilet. Observed when:

1. 1 Drink plenty of liquid;
2. 2 Urinary infections.

Olakiuria is the opposite condition to that described above. Characteristic for:

1. 1 Low intake of fluid into the body;
2. 2 Neuro-reflex disorders.

Strangury is painful urination.

Dysuria is a urination disorder that combines symptoms such as changes in urine volume, frequency and pain. She usually accompanies.

4.3. Color

Is a direct reflection of concentration. In a healthy person, deviations in color from straw yellow to amber are allowed.

The color of urine is also influenced by special substances, the basis of which are blood pigments. A dark yellow color is observed when the amount of coloring substances dissolved in it significantly exceeds the norm. Characteristic of such conditions:

1. 1 Edema;
2. 2 Vomiting;
3. 4 Burns;
4. 4 Stagnant kidney;
5. 5 Diarrhea.

1. 1 Diabetes mellitus;
2. 2 Diabetes insipidus.

The dark brown color is explained by an increase in the level of urobilinogen. It is a diagnostic criterion for hemolytic anemia. Urine may turn dark brown when taking sulfonamides.

Dark, practical black color can indicate several conditions:

1. 1 Alkaptonuria (due to homogentisic acid);
2. 2 Acute hemolytic kidney;
3. 3 Melanosarcoma (obtains this shade due to the presence of melanin).

Urine turns red if it contains fresh blood or red pigments. This is possible with:

1. 1 Kidney infarction;
2. 2 Renal failure;
3. 3 Damage and trauma to the urinary tract;
4. 4 Taking certain medications (for example, rifampicin, adriamycin, phenytoin).

The appearance of “meat slop” is explained by the presence of altered blood, which is characteristic of acute glomerulonephritis.

A greenish-brown tint (compared to the color of beer) appears if bilirubin and urobilinogen enter the urine. This deviation from the norm often indicates parenchymal jaundice.

If the shade is rather greenish-yellow, which may indicate the presence of bilirubin alone, and is considered a symptom of obstructive jaundice.

4.4. Transparency

Normally, urine is clear. However, in the presence of pathological components and impurities (proteins, leukocytes, erythrocytes, epithelium, bacteria, salts), it can be cloudy, cloudy and milky.

Several manipulations can be carried out in advance to narrow the range of possible substances that make up the sediment to certain salts.

When, when heated, the test tube with the test material becomes transparent again, we can conclude that it contained urates.

If the same happens upon contact with acetic acid, we can assume the presence of phosphates in the sample. If an identical effect is observed when mixed with hydrochloric acid, then there are .

For more accurate data, microscopy of the sediment is performed.

4.5. Smell

The smell of urine is usually specific and not strong. An ammonia odor may appear if there is bacterial contamination of the sample. A fruity smell (of rotting apples) is considered an indicator of the presence of ketone bodies.

4.6. Relative density (SG)

This indicator is considered very important, since it is used to judge the concentration function of the kidneys and its ability to dilute.

The measurement is carried out using a specially designed device - a urometer. During the study, attention is primarily paid to the content of electrolytes and urea, and not to substances with high molecular weight (proteins, glucose, etc.).

Normally, the relative density of the morning urine portion is determined in the range from 1.012 to 1.025. During the day it can fluctuate between 1001 - 1040, therefore, if a patient is suspected of having a decrease in the concentrating ability of the kidneys, it is usually prescribed.

Hypersthenuria – an indicator higher than normal. Its cause may be:

1. 1 Toxicosis of pregnant women;
2. 2 Progressive edema;
3. 3 Nephrotic syndrome;
4. 4 Diabetes mellitus;
5. 5 Use of radiopaque agents.

Hyposthenuria - decreased specific gravity. Observed in the following conditions:

1. 1 Malignant hypertension;
2. 2 Chronic renal failure;
3. 3 Diabetes insipidus;
4. 4 Damage to the kidney tubules.

Isosthenuria is a condition in which the density of urine is equal to the density of blood plasma (within 1010-1011).

5. Chemical properties

This is the second group of urine indicators that characterize the patient’s health status.

5.1. Medium reaction (pH)

Normally, urine pH ranges between 5-7. Acid reaction (pH<5) может быть следствием:

1. 1 Increased consumption of meat products;
2. 2 Metabolic or respiratory acidosis (as a consequence of various pathological processes), coma;
3. 3 Acute glomerulonephritis;
4. 4 Gout;
5. 5 Hypokalemia.

An alkaline reaction (pH>7) occurs when:

1. 1 Vegetable diet;
2. 2 Chronic renal failure;
3. 3 Metabolic or gas alkalosis;
4. 4 Hyperkalemia;
5. 5 Active inflammatory processes in the urinary system.

5.2. Protein Determination (PRO)

Normally, it is not detected or an insignificant amount is detected. A condition in which this threshold is exceeded is called proteinuria. It is customary to distinguish several types of proteinuria:

1. 1 Prerenal proteinuria is associated with pathological processes in the human body that are accompanied by an increase in protein concentration in the blood plasma (myeloma, for example).
2. 2 Renal - one that is a consequence of damage to the glomerular filter or dysfunction of the renal tubules. The diagnostic criterion for the severity of the pathological process is selectivity - the greater the number of large protein molecules found in secondary urine, the more serious the situation.
3. 3 Postrenal proteinuria is a manifestation of inflammatory processes in the reproductive system and surrounding tissues (vulvovaginitis, balanitis, and so on).
4. 4 Proteinuria can also be physiological, for example, during emotional overload, exposure to cold or sun, in children in a standing position, during long walking or running.

5.3. Determination of glucose (GLU)

Normally, this substance cannot be detected in urine due to its low content. Glucosuria is the name given to a condition in which glucose levels exceed 0.8 mmol/l. This occurs when the so-called renal glucose threshold is exceeded.

That is, when its concentration in the blood exceeds 9.9 mmol/l, it freely passes the barrier and enters the urine. There are the following types of glucosuria:

1. 1 Nutritional (large amounts come from food);
2. 2 Emotional;
3. 3 Medicinal.

Pathological glycosuria is usually divided into renal (manifests itself in various kidney diseases) and extrarenal, which is considered a consequence of the following diseases:

1. 1 Diabetes mellitus;
2. 2 Thyrotoxicosis;
3. 3 Pheochromocytomas;
4. 4 Acute pancreatitis and other diseases of the pancreas;
5. 5 Itsenko-Cushing's disease;
6. 6 Cirrhosis of the liver;
7. 7 Poisoning.

5.4. Determination of hemoglobin (Hb)

It is believed that hemoglobin is found in a portion of urine during the rapid breakdown (hemolysis) of red blood cells. Such a process may be infectious, immunological or genetic in nature. Most often, hemoglobinuria is detected with:

1. 1 Hemolytic anemia;
2. 2 Transfusion of incompatible blood;
3. 3 Internal injuries (crash syndrome);
4. 4 Severe poisoning;
5. 5 Direct damage to kidney tissue.

Hemoglobinuria is dangerous because it is an impetus for the development of acute renal failure.

5.5. Determination of ketone bodies (KET)

Ketonuria is a special indicator of urine analysis, which reflects the failure of metabolic processes occurring in the body. In this case, the following substances are detected: acetone, beta-hydroxybutyric, acetoacetic acids. Ketonuria occurs against the background of:

1. 1 Diabetes mellitus;
2. 2 Carbohydrate fasting, diets;
3. 3 Severe toxicosis (more often in children);
4. 4 Dysentery;
5. 5 Severe CNS irritation;
6. 6 Overproduction of corticosteroids.

5.6. Determination of bilirubin (BIL)

Bilirubinuria is a pathological condition in which unchanged bilirubin is detected in the urine. When the mechanisms that utilize bilirubin fail, the kidneys take on part of the work. Bilirubinuria is typical of many liver diseases:

1. 1 Cirrhosis;
2. 2 Hepatitis;
3. 3 Jaundice (parenchymal and mechanical);
4. 4 Gallstone disease.

5.7. Determination of urobilin bodies (UBG)

Urobilinuria occurs when the liver does not function properly. However, intestinal pathology (where this substance is formed) and processes leading to the breakdown of red blood cells also contribute to the appearance of urobilinogen in the urine.

A high content of urobilinogen bodies in the sample (UBG in the analysis form) is detected when:

1. 1 Hepatitis;
2. 2 Sepsis;
3. 1 Hemolytic anemia;
4. 4 Cirrhosis;
5. 5 Intestinal diseases (inflammation, obstruction).

6. Microscopic examination of sediment

Microscopic examination of organized and unorganized urine sediment is of great importance in diagnosis. For this purpose, the laboratory technician lets the resulting sample sit for about two hours, then centrifuges it, drains the liquid, and examines a drop of sediment under a microscope.

At low magnification, the cylinders within the field of view are counted, and at high magnification, leukocytes, erythrocytes and other cellular elements are counted.

Counting the number of cellular elements in a material greatly facilitates the use of Goryaev’s camera.

6.1. Red blood cells (BLD)

Normally there are, but their number is limited to one cell in the field of view in men and up to three in women).

– a condition in which more red blood cells are found in the urine. There are macrohematuria (the presence of blood clots can be determined with the naked eye) and microhematuria (the presence of red blood cells can only be detected using a microscope).

Figure 1 - Changed erythrocytes in urine under a microscope, native preparation. Source Masaryk University (https://is.muni.cz/do/rect/el/estud/lf/js15/mikroskop/web/pages/zajimave-nalezy_en.html)

In addition, glomerular (renal) hematuria is distinguished, which manifests itself in kidney diseases of various origins, medicinal and toxic damage to the renal tissue, and non-glomerular, which is associated with the inflammatory process, injuries and oncological diseases.

Figure 2 - Unchanged erythrocytes (native preparation, red arrow indicates erythrocyte and leukocyte). Source Masaryk University

6.2. Leukocytes (LEU)

In a healthy man, leukocytes in the urine are represented by a small number of neutrophils (up to three), in women there are slightly more of them (up to six).

An increase in the level of white blood cells in the urine is called leukocyturia. This always indicates inflammatory processes in the kidneys or urinary tract, such as:

1. 2 Glomerulonephritis;
2. 3 Kidney tuberculosis;
3. 5 Urethritis;
4. 6 Fever.

If among all the cells there are noticeably more eosinophils, then they talk about the allergic genesis of the disease, if there are lymphocytes - about the immunological one.

Figure 3 - Leukocytes in urine under a microscope

6.3. Epithelium

Normally, microscopy reveals up to 5-6 cells. However, the elements should be distinguished from each other, since they reflect different clinical manifestations:

1. 1 Flat epithelium enters the material from the external genitalia. Often observed with urethritis in men, in poorly collected samples in women.
2. 2 Transitional epithelium is part of the mucous membrane of the urinary tract. Found in cystitis, neoplasms, pyelitis.
3. 3 Renal epithelium, present in large quantities in TAM, indicates the following conditions: acute and chronic kidney damage, intoxication, fever, infection.

6.4. Cylinders

These are protein or cellular elements originating from the tubular epithelium.

1. 1 Hyaline (protein) appear when:
   • dehydration of the body;
   • nephropathy in pregnant women;
   • fevers;
   • poisoning with salts of heavy metals.
2. 2 Waxy (protein) speaks of:
   • nephrotic syndrome;
   • amyloidosis.
3. 3 Cellular casts can indicate problems of a very wide etiology and are a direct indication of more detailed analyzes.

6.5. Slime

Normally found in small quantities. At higher levels, mucus may indicate the following diseases:

1. 5 Urethritis;
2. 4 Kidney stone disease;
3. 5 Incorrect sample collection.

Bibliography

1. 1 Kozinets G.I. Interpretation of blood and urine tests and their clinical significance / G.I. Kozinets. - M.: Triad X, 1998. – 100 p.;
2. 2 Yurkovsky O.I. Clinical analysis in medical practice / O.I. Yurkovsky, A.M. Gritsyuk. – K.: Technology, 2000. – 112 p.;
3. 3 Medvedev V.V. Clinical laboratory diagnostics: Doctor's reference book/ V.V. Medvedev, Yu.Z. Volchek / Edited by V.A. Yakovleva. – St. Petersburg: Hippocrates, 2006. – 360 pp.;
4. 4 Zupanets I.A. Clinical laboratory diagnostics: research methods: Textbook. manual for students special. “Pharmacy”, “Wedge. Pharmacy", "Lab. Diagnostics" of universities /I.A. Zupanets, S.V. Misyurova, V.V. Propisnova et al.; Ed. I.A Zupanca – 3rd ed., revised. and additional – Kharkov: NUPh Publishing House: Golden Pages, 2005. – 200 pp.; 12 s. color on;
5. 5 Morozova V.T. Urine examination: Textbook. allowance / V.T. Morozova, I.I. Mironova, R.L. Shartsinevskaya. – M.: RMAPO, 1996. – 84 p.

Clinical task on the topic of the article:

A 45-year-old man visited a nephrologist for examination regarding microhematuria. Microhematuria was first identified 6 months ago (the patient changed jobs and underwent a medical examination for health insurance), which was reported to him twice in the last six months by his attending physician.

Previous urine tests did not reveal any pathological changes. The patient has never reported gross hematuria (red-colored urine, blood in the urine), has not experienced any urinary tract symptoms, and currently feels in excellent shape.

There is no history of serious illnesses, no symptoms of visual or hearing impairment. There is no mention of kidney disease in relatives in the family history. According to the patient, he drinks about 200 grams of vodka a week and smokes 30 cigarettes a day.

Inspection data

The patient has no signs of being overweight. Pulse – 70 beats per minute, blood pressure – 145/100 mm Hg. An examination of the cardiovascular, respiratory, nervous systems, and abdominal organs did not reveal any abnormalities.

Fundoscopy (examination of the fundus) revealed tortuous arteries and veins of the fundus, perpendicular branching of the retinal arteries.

Research results

Questions

1. 1 Most likely diagnosis.
2. 2 What further tests should be ordered?
3. 3 What recommendations should be given to the patient?
4. 4 How to interpret the results of a biochemical blood test?

Problem solving and patient management tactics

Microscopic hematuria can occur as a result of a wide range of pathologies (for example, prostate diseases, urolithiasis), but its combination with arterial hypertension, proteinuria (increased protein in the urine), impaired renal function (increased levels of creatinine and urea) indicates that the patient has chronic glomerulonephritis.

An increase in the level of GGTP in a biochemical analysis may indicate liver damage as a result of chronic alcohol consumption (here it is necessary to clarify the life history of this patient).

The most common causes of microhematuria:

1. 1 Chronic glomerulonephritis, including immunoglobulin A (Ig A) nephropathy;
2. 2 Thin basement membrane disease (benign hematuria);
3. 3 Alport syndrome.

Ig A nephropathy, the most common glomerulonephritis in developed countries, is characterized by diffuse mesangial deposits of IgA.

Patients often experience episodes of gross hematuria (red urine) in response to the development of inflammatory diseases of the upper respiratory tract.

In most cases, the triggering factor of the disease cannot be identified. There is often an association with Henoch-Schönlein purpura and other autoimmune diseases, alcoholic cirrhosis of the liver, infections, and oncology.

In this patient, immunoglobulin nephropathy may be combined with alcoholic liver disease, which requires clarification. 2 out of 10 patients with IgA nephropathy develop end-stage chronic renal failure within 20 years.

Thin basement membrane disease is a hereditary disease that is accompanied by the determination of red blood cells, protein in the urine (minimal proteinuria), and normal kidney function tests that do not deteriorate over time.

Electron microscopy reveals diffuse thinning of the glomerular basement membranes (normally the thickness of the basement membrane is 300 - 400 nm, while in patients with benign hematuria the thickness of the glomerular basement membranes is 150 - 225 nm).

Alport syndrome is a progressive hereditary disease (the gene is inherited on the X chromosome in a dominant manner, men are more often affected) of the glomeruli of the kidneys, which is associated with deafness and visual impairment.

This patient needs to undergo a kidney biopsy for histological verification and an accurate diagnosis.

Since the patient is over 40 years old, it is necessary to conduct a PSA test, transrectal digital examination (to exclude prostate cancer), and if bladder cancer is suspected, urine cytology, ultrasound, and cystoscopy of the bladder.

To assess the condition of the liver, it is necessary to perform an ultrasound examination and, if necessary, decide on a liver biopsy.

The patient should be advised to stop drinking alcohol and regularly monitor blood pressure. The patient should be regularly examined by a nephrologist, as he is at high risk for the progression of renal failure, with a high probability of undergoing hemodialysis and/or kidney transplantation.

The patient should be referred to a cardiologist for blood pressure profiling and antihypertensive therapy.

Moderately elevated creatinine levels indicate glomerular damage. Currently, there is no convincing evidence of the effectiveness of immunosuppressive therapy in patients with immunoglobulin (Ig A) nephropathy.

Key points

1. 1 Patients with isolated hematuria under 50 years of age should be referred to a nephrologist.
2. 2 Patients over 50 years of age are initially referred to a urologist to exclude pathologies of the bladder and prostate.
3. 3 Even a slight increase in plasma creatinine indicates significant impairment of renal function.
4. 4 Alcohol-induced liver damage is not accompanied by severe symptoms.

Synonyms: relative density of urine, specific gravity, SG

General information

Relative density of urine (specific gravity) is a OAM parameter that determines the concentration of components dissolved in it (salt, urea, etc.) in relation to the total volume of urine excreted during one urination.

This indicator allows you to assess the condition and performance of the kidneys, in particular, their ability to concentrate and dilute urine, as well as timely identify and prevent diseases of the urinary system.

The process of urine formation in the kidneys occurs in two stages:

• filtration;
• reabsorption.

At the first stage, blood plasma, containing many substances dissolved in it, is filtered in the glomeruli of the kidneys - primary urine is formed. Then, already in the kidney tubules, repeated filtration occurs, during which the residual amount of components useful to the body is absorbed back into the blood. The output is secondary urine containing a dry residue: metabolic products, urea and uric acid salts, toxins, chlorides, ammonia ions, sulfates, etc. It is secondary urine that is released from the body during urination.

The specific gravity of urine is affected by:

• ratio of components in dry residue;
• the patient’s usual diet;
• water regime;
• Times of Day;
• degree of physical activity;
• intensity of extrarenal losses (fluid loss through the skin and lungs), etc.

Drinking insufficient amounts of liquid, the presence of protein and/or glucose in the urine increase the concentration of dry matter, and accordingly, the density index also increases. This condition is called “hypersthenuria”.

In case of fluid retention in the body or in a saturated water regime, the dry residue is diluted and, as a result, the specific gravity of urine decreases. This process is called “hyposthenuria”.

The extreme degree of kidney damage (complete loss of concentration function) is a state of “isosthenuria”, when the density of urine becomes monotonous (the inability of the kidneys to produce urine with a higher or lower specific gravity).

In OAM, urine density is abbreviated SG. To determine it, a medical device is used - a urometer, which has a special scale. The biomaterial obtained from the patient is placed in the urometer cylinder and the foam is removed using filter paper. The laboratory worker then records the position of the meniscus on the cylinder and marks the value on the scale. The obtained data is entered into a form with a decoding of the OAM result.

Indications for determining the specific gravity of urine

The direction and interpretation of the results of OAM and functional tests is carried out by a nephrologist, urologist, gynecologist, therapist, family doctor, pediatrician and other specialists.

• Mandatory screening in the diagnosis of somatic diseases;
• Preventive examination, clinical examination;
• Mandatory analysis in the program of preparation and management of pregnancy;
• Determination of excess or insufficient hydration (saturation of the body with fluid);
• Pathologies in the functioning of the heart and circulatory system;
• Life-threatening conditions (sepsis, shock, massive burns, serious injuries);
• Diagnosis of diseases:
  • glomerulonephritis (damage to the glomeruli);
  • pyelonephritis (kidney inflammation);
  • renal failure;
  • kidney infarction;
  • oncological processes;
  • amyloidosis (starch accumulation), etc.;
• Inflammatory and infectious pathologies of other organs of the genitourinary system: bladder, ureters, urethra, prostate, etc.;
• Diagnosis of hypo- and hypernatremia (decrease or increase in sodium levels in the blood);
• Diagnostics of diabetes (sugar and non-diabetes).

Values ​​are normal

On a note: During the day, the specific gravity of urine can fluctuate significantly (from 1.008 to 1.025). This is due to the speed of metabolic processes and the amount of water entering the body. The more a person drinks, the more often they urinate and the less concentrated the urine. The exception is the urine of diabetic patients. Its density remains high even with significant daily amounts.

In the case of proteinuria (protein in the urine), the normal values ​​are reviewed and the following amendments are made (“minus” the number of divisions on the urometer scale):

Increased density of urine

• Dehydration due to insufficient water intake, large fluid loss (diarrhea, vomiting, sweating);
• Increased swelling due to low blood flow;
• Kidney diseases associated with impaired excretory function:
  • acute glomerulonephritis;
  • renal failure, etc.;
• Uncontrolled diabetes mellitus;
• Oliguria (excretion of a significant amount of urine) due to the formation of exudate (pathological fluid due to inflammation) in the kidney cavity.

Density reduced

• Polyuria (frequent urination) with heavy fluid intake;
• Polyuria due to taking diuretics;
• Nutritional dystrophy (hyposthenuria is temporary);
• Interstitial nephritis (inflammation of the kidney tubules) in chronic and acute form;
• Glomerulonephritis, pyelonephritis in acute and chronic form;
• Other kidney diseases:
  • nephritis;
  • To do this, the patient must collect about 8 portions of urine at regular intervals during the day (optimally every 3 hours). The specialist then uses a urometer to determine the difference between nighttime and daytime diuresis. In this case, a discrepancy of approximately 30% is considered acceptable.
• A test with dry food or concentration - for the duration of the study (usually one day), all foods containing liquid (drinks, soups, sauces, etc.) are removed from the patient’s diet. The amount of drinking water consumed is limited to a few sips per day.
  • Biomaterial is collected every 4 hours and immediately sent to the laboratory (therefore, it is advisable to carry out the test in a hospital). If urine density is low, then the inability of the kidneys to perform a concentration function should be suspected. If the test result is within the normal range or slightly increased, then the kidneys are functioning normally.

Various tests are used to diagnose human health. Urinalysis is one of the most informative assessment methods. During it, various indicators are assessed, the values ​​of which reveal different pathology.

Specific gravity normcan be called one of the important parameters that determine when examining urine during general analysis. may be upgraded or downgraded for a number of reasons. Any deviation in the indicator requires attention and clarification of the cause.

What is meant by specific gravity?

Specific gravity of urine means how densely the dissolved substances are present in it. Various salts, acids and other breakdown products are excreted in the urine. The more of them are contained in urine, the more dense it is.

What is he talking about? density? Thanks to this indicator, the filtering function of the kidneys and their ability to dilute urine are assessed. A decrease in density may indicate renal failure, and an increase may indicate insufficient urine excretion.

If significant deviations are detected, additional diagnostics of the body and analyzethe reason for this condition. Kidney dysfunction affects the entire body and causes serious complications.

Urinalysis, urine density, as one of its parameters

Characteristics of the composition and appearance of urine can provide a lot of information about a person's health status. The most basic test is a general urine test. During urine test study parameters - color, smell, content of salts, acids and other substances.

One of the parameters is specific gravity or urine density . This indicator measured using a special device called a urometer.Unit of measurementThe density of urine is g/liter.

General analysis urine serves as the main type of research. To clarify its results, other, narrower analyzes can be used:

• Zemnitsky method. With its help, the ability of the kidneys to filter, excrete and dilute urine is determined. For analysis, collect a sample during the day at regular intervals in separate jars;
• The concentration method involves severe fluid restriction and collection of samples over a period of time. days . There are contraindications;
• The dilution method is to study the dilution function of the kidneys with increased fluid intake. Dosage liquids is selected depending on masses bodies. There are also contraindications.

Rules for preparing for urine analysis in adults (men, women, pregnant women)

It is very important to properly prepare and collect the sample forgeneral urine test. This will allow you to obtain the most reliable analysis results.

The preparation is as follows:

• the day before collection, avoid coloring foods, salty, fatty and spicy foods;
• avoid physical activity;
• give up alcohol;
• stop taking medications. If it is impossible to cancel, notify your doctor.

• before collection, it is necessary to carry out hygiene procedures and wash the genitals;
• women use a tampon in case of heavy discharge or menstruation;
• prepare a sterile container for collecting the sample;
• start urinating into the toilet, through interval stop in 2-3 seconds and collect the middle portion into a container, then you can do it again urinate in the toilet;
• Urine collected in the morning on an empty stomach is best suited for analysis. As a last resort, it is necessary to collect a sample no earlier than 5-6 hours after the last urination;
• A urine sample must be submitted for testing no later than 1-2 hours after collection. Long-term storage is unacceptable and leads to unusability of urine.

Tips for preparing your child for urine testing

Rules for preparing and submitting a urine sample to study in adults and children are almost the same. The slight differences are in the collection. U little ones For children who do not yet know how to go potty on their own, urine is collected using a special urinal. It can be purchased at any pharmacy.

Collecting from a child's potty, diapers and diapers is strictly prohibited. With this collection, bacteria, dirt particles and fibers enter the urine, which ultimately leads to distorted results.

Indicator norms

Norms for the specific gravity of substances in urine are not permanent. What do they depend on? To standards It is influenced not only by age and gender factors, but also by many others:

• ambient temperature level;
• amount of liquid drunk;
• Times of Day;
• excess salt or spices in food;
• the volume of water that is released through sweat and breathing.

Despite this, there are certain ranges of values ​​for different ages by which kidney function is assessed.

In men

The norms for various urine indicators differ between men and women. Typically, men use less liquids during the day. For this reason, the density of their urine is slightly higher. The norm in men is a value of 1.020 – 1.040 g/liter.

Among women

Among women this indicator is practically not is different from male. By nature, women monitor their slimness and health, so they drink more liquid. Therefore, the norm is considered to be a value in the range from 1.003 to 1.025 g/liter.

In pregnant women

During pregnancy, toxicosis, nausea and frequent vomiting which lead to fluid loss. Or, on the contrary, swelling. As a result, the specific gravity of urine can vary significantly in different directions during certain periods of pregnancy.

Range normal density in pregnant women slightly wider than women in general. It varies from 1.001 to 1.035 g/liter.

Children's indicators

In children, there are large differences in density depending on age:

• after birth - 1.007 - 1.017 g/liter;
• up to six months – 1.003 – 1.005 g/liter;
• up to 1 year – 1.005 – 1.015 g/liter;
• up to 3 years – 1.010 – 1.018 g/liter;
• up to 5 years – 1.013 – 1.020 g/liter;
• up to 12 years – 1.009 – 1.025 g/liter

Indicators for the elderly

With age, changes occur in the body. The functions of almost all organs decrease and metabolic processes slow down. This also applies to kidney function. The ability of the kidneys to filter is reduced, which leads to an increase in urine density. The normal value for older people is considered to be from 1.01 to 1.04 g/liter.

Hypersthenuria

When density increases above the maximum permissible values, a certain state of the body occurs, which is called hypersthenuria y. It is noted when increasing urine specific gravity above normal already at a value of 1.04 g/liter.

Symptoms The following signs of hypersthenuria include:

• reducing the number and size of urine portions;
• darkening;
• the appearance of clots or sediment;
• the appearance of pain in the lower abdomen;
• weakness and increased fatigue;
• swelling of the whole body.

Causes in adults

All reasons contributing to the development of hypersthenuria can be divided into physiological and pathological. The first type includes:

• small amount of fluid consumed;
• taking medications (laxatives, antibiotics);
• excessive sweating in hot weather or during physical activity;
• dehydration as a result of poisoning, diarrhea, vomiting;
• severe body burns.

In these cases, it is necessary to replenish the fluid supply in the body, which will help reduce relative density substances in urine.

Hypersthenuria can occur as a result of the development of certain pathologies. The second group of factors includes the following diseases:

• heart failure, which is accompanied by edema;
• diabetes mellitus, which is accompanied high concentration of glucose in the blood;
• presence of diseases inflammatory nature in the urinary system and kidneys;
• acute or chronic form of glomerulonephritis;
• development of oliguria;
• pathologies causing excess protein concentration in urine;
• disorders of the thyroid gland (for example, hypothyroidism).

In children

Many parents, seeing in the analysis results thaturine density in children elevated and, they don’t know, what does this meanand what needs to be done. The phenomenon of hypersthenuria can be diagnosed even in kids. Its symptoms are similar to those in adults. Among the reasons are:

• pathologies of congenital or acquired nature of the urinary tract;
• frequent cases of poisoning, diarrhea and vomiting;
• in very small babies children advanced level density may occur due to an excess of fatty and protein foods in the mother’s diet.

In the elderly

Hypersthenuria often occurs in the elderly of people due to decreased kidney function. As a result, the filtration capacity of glomerular filtration decreases and resistance in the vessels of the kidneys increases. All this leads to the fact that saturation urine output decreases in older people.

Hyposthenuria

With a strong decrease in urine density a state arises hyposthenuria . In this case, there is an increased urination , severe discoloration of urine, possible swelling. Too low specific gravity of urine is observed when the indicator values below normal at a value of 1 g/liter.

Causes of decreased density in adults

There are certain Causes of low urine density:

• drinking large amounts of liquid;
• reception diuretics;
• severe food restrictions, strict diets, fasting.

Reducing water consumption and normalizing nutrition help ensure that the specific gravity returns to normal without additional treatment.

The danger should be caused by hyposthenuria, which occurs against the background of pathologies:

• psychological diseases accompanied by a great feeling of thirst;
• diabetes insipidus;
• pathologies of the central nervous system (encephalitis, meningitis);
• renal failure;
• amyloidosis;
• urolithiasis disease;
• kidney tumors;
• infectious diseases.

In this case, hyposthenuria is a symptom of the underlying disease, and treatment should be aimed precisely at the main reason.

Why does a child’s density decrease?

In children noted after birth decreased urine density . This is a normal occurrence during the first month of life. Subsequently, this indicator returns to normal.

If a low level of density is diagnosed in older children, then first monitor the dynamics indicator over a period of time. In case of constant low density level The child has a thorough examination and identification of the cause is required. The most common cause of the condition is renal failure.

Factors reducing urine density in the elderly

It is considered not uncommon reduction in permissible urine specific gravity standardsin older people. Age-related changes affect all organs, including the urinary system. As a person ages, the immune system and the body's resistance to various diseases decrease.

Factors in the development of hyposthenuria can be:

• urinary tract infections;
• prostatitis;
• gout;
• diabetes ;
• urolithiasis, etc.

Significant deviations from the norms of the specific gravity of urine should alert a person. Hypersthenuria and hyposthenuria can cause serious complications and therefore require consultation with a nephrologist or urologist. You should initially consult a therapist.

It is imperative to establish the exact cause of deviations in urine density. Therapy is selected depending on the identified disease.

A prerequisite is adherence to the dietary diet:

• refusal of fatty, salty, smoked and spicy foods;
• getting rid of bad habits;
• compliance with the drinking regime.

The diet helps speed up the treatment process and improve the patient’s condition. In addition, the doctor’s advice includes:

• regular visit doctor to assess health status;
• conducting healthy lifestyle;
• analysis at least 2 times a year;
• Seeing a doctor immediately after the appearance of unpleasant symptoms or problems with urination.

Conclusion

Not all people know what's happened density of urinewhat diseasesit changes and why it is determined. Specific gravity is one of the main indicators of urine, on the basis of which the functional abilities of the kidneys are determined.

There are certain ranges permissible density values. If there are deviations in one direction or another, you must immediately consult a doctor and find out the cause. Treatment is selected after an accurate diagnosis is made.

Lack of treatment can lead to serious consequences and complications.

The relative density of urine is an important diagnostic indicator, according to which the pathological conditions of the patient are determined. Depending on the disease and the stage of its progression, urine can have completely different relative densities, including reduced ones.

The relative density of urine is below normal - what might it indicate?

This test is carried out to determine the current functioning of the kidneys. These include Zimnitsky and Nechiporenko samples. The latter belong to the category of the most detailed laboratory studies, the results of which take into account the concentration of urea and salts. If these substances are contained in quantities that differ from the norm to a lesser extent, then the patient clearly has a reduced density of urine - hyposthenuria.

Since the specific density of urine is an integral part of the functional indicators of kidney function, it can be diagnosed if there is a suspicion of:

1. Kidney pathologies.
2. Inflammatory processes in other structures of the genitourinary system.
3. Somatic disorders.

Normal density values ​​in accordance with the mechanisms of urine formation

There are several stages of urine formation, after which the material necessary for analysis is formed.

At the first stage, the formation of urine of the primary composition occurs in the renal glomeruli. In this case, the blood, under the influence of internal renal pressure, is cleansed of toxins and other elements formed as a result of the past cycle.

In the second stage, the products separated from the blood go through the stages reabsorption through jade channels. Any useful substances that could be separated under pressure are returned to the body. The output is urine, which contains extremely harmful substances such as chlorine, sodium, various sulfates, and so on.

It is this obtained material that is used for analysis using a urometer.

Based on the results obtained, namely fixing the content of salts and urea, the value is determined. The latter cannot be called constant, since throughout the day, in the same biological material, the density can change several times. This depends on food, drinks, as well as banal fat loss through sweating.

Indicators are within normal limits according to the principle of age division

• baby, 1 day old - 1,008-1,018 (density according to urometer data);
• 6 months - 1,002-1,004 .
• from six months to 12 months – 1,006-1,016 .
• age from 1 to 5 years – 1,010-1,020 .
• from 6 to 8 years – 1,012-1,020 .
• from 9 to 12 – 1,012-1,025 .
• adult men and women - 1,010-1,025 .

It is worth noting that upon reaching the age of twelve, the density of the analyzed urine is completely comparable to that for the biological material of an adult.

Causes of decreased urine density

The study can show the presence of hyposthenuria only if the density is reduced to 1,005-1,010 . In this case, such indicators indicate a decrease in renal function, an integral part of which is antiarrhythmic hormones. If the amount of the latter increases, the fastest possible absorption of water in the body is provoked, resulting in a decrease in the concentration of urine.

Thus, the action works completely in the opposite direction, that is, in the absence or decrease in the amount of the mentioned hormones, urine concentrates too much, due to an increase in the amount of water. Given such a sharp increase in the amount of liquid being analyzed, its specific density decreases accordingly.

This is one of the most common reasons for the decline in the mentioned indicator, but, in fact, there are much more of them.

Decreased urine density in pregnant women

It is worth immediately noting that the normal indicator for a pregnant woman is 1.010-1.020. The causes of hyposthenuria during pregnancy may be:

• Any renal pathology.
• Hormonal imbalance.
• Urinating too frequently.
• Common toxicosis.

Urine density in newborns and children

At the time of birth, the indicator may radically deviate from the established norm. After some time, this indicator returns to normal. If a one-year-old child is diagnosed with hyposthenuria, then until the age of two there is absolutely no need to worry.

Otherwise, you should contact a specialist and undergo an examination.

Decreased urine density in adults

In the adult population, there are many more pathological reasons for the formation and progression of decreased urine density. These include:

1. Kidney failure, which has developed into a chronic disease.
2. Central diabetes.
3. Pyelonephritis.
4. Chronic nephritis.
5. The consequence of any inflammatory processes in the body due to the resorption of inflamed areas.
6. Nephrosclerosis.
7. Jade in intense form.
8. Dystrophy caused by starvation.
9. Glomerulonephritis.
10. Exposure to antibiotics or diuretics.

It is worth paying attention to the fact that a decrease in the specific density of urine can be caused by alcoholism or drug use.

What to do based on the diagnostic results?

If a decrease in the specific gravity of urine is caused by a natural factor, such as the consumption of a certain type of food and liquid, then there is no need to worry, but, on the contrary, exclude certain types of foods from the diet.

If the cause is one of the previously mentioned diseases, then you must immediately contact a specialist for advice and additional examinations. Through the latter, special medications are prescribed, during which a decrease in urine density can also be diagnosed.