Study of methods for detecting bile pigments in urine. Urobilinogen in urine - what does it mean. The reasons for the increase in urine indican in children and adults

Bilirubinuria - increased excretion of bilirubin (direct, associated with glucuronic acid) in the urine, is observed with parenchymal and subhepatic jaundice, appears with an increase in the content of direct bilirubin in the blood over 3.4 μmol / l. This value is the "renal bilirubin threshold".

Urobilinuria(urobilinogenuria) occurs in the following diseases:

a) parenchymal lesions of the liver (hepatitis), when the bulk of bile continues to enter the intestine, but the urobilinogenic bodies returning through the portal vein do not undergo the usual transformations for them and are excreted in the urine due to functional liver failure;

b) hemolytic processes with increased formation of urobilinogenic and stercobilinogenic bodies in the intestine;

c) with intestinal diseases, accompanied by increased reabsorption of stercobilinogen in the intestine (enterocolitis, constipation, intestinal obstruction).

The urine of a healthy person contains traces of urobilinogen (normally 0-6 mg is released per day).

All elements of the urinary sediment are divided into unorganized and organized ones.

Unorganized(inorganic) elements of urinary sediment - crystalline and amorphous salts. The diagnostic value of the study of organic sediment of urine.

Give a clinical assessment of leukocyturia.

In the sediment of the urine of a healthy person, single leukocytes are found - 0-6 in the field of view of the microscope.

Leukocyturia - excretion of leukocytes with urine above normal (more than 5-6 in the field of view of the microscope).

Piuria - the allocation of leukocytes more than 60 in the field of view of the microscope.

Determine the source of leukocyturia with a three-glass Thompson test:

When urinating in the morning, the very initial portion of urine is discharged into the first glass, the rest of the urine in the second, and its remainder in the third. The predominance of leukocytes in the first portion indicates urethritis, prostatitis, and in the third, bladder disease. An even distribution of leukocytes in all portions indicates kidney damage (pyelonephritis).

Confirm the presence of an inflammatory process by detecting "active leukocytes" - Sternheimer-Malbin cells:

"Active leukocytes" are neutrophils that enter the urine from an inflammatory focus. They are stained with paint - a water-alcohol mixture of 3 parts of gentian violet and 97 parts of safranite - blue, in urine with low relative density are in a state of Brownian motion and are called "active". Such leukocytes appear in urine in the presence of an inflammatory process in conditions of iso - or hypostenuria: with acute and exacerbation of chronic pyelonephritis, with glomerulonephritis, multiple myeloma, chronic prostatitis. Often, "active leukocytes" are detected in chronic renal failure, regardless of the etiology of uremia, which is associated with isostenuria.

Leukocyturia occurs in bacterial inflammatory processes of the urinary system ( infectious leukocyturia), with aseptic, autoimmune inflammation of the renal tissue ( aseptic leukocyturia). In infectious leukocyturia (for example, with pyelonephritis), neutrophils predominate in urine leukocytes, while in aseptic leukocyturia (with glomerulonephritis, interstitial nephritis, amyloidosis) lymphocyturia.

Misinterpretation of any leukocyturia as infectious entails a fundamentally incorrect diagnosis and treatment (for example, unjustified use of antibiotics). "Active leukocytes" can be found in urine both in infectious (20-70% or more "active leukocytes") and in aseptic leukocyturia (but not more than 10%). Therefore, to clarify the genesis of leukocyturia, it is important study of leukocyte morphology urine (neutrophils or lymphocytes), determination of the percentage of "active leukocytes", the degree of bacteriuria.

Pyuria is observed with purulent inflammation of the urinary tract and with the breakthrough of nearby abscesses. Renal pyuria occurs only with apostomatoenic nephritis (when an abscess in the renal tissue opens into the urinary tract).

The excretion of red blood cells in the urine is called hematuria. In the urine of a healthy person, there can be no more than 1 erythrocyte per 10-12 fields of view.

Hematuria should be distinguished from accidental admixture of blood to the urine that does not originate from the kidneys or urinary tract. This can be observed in men with prostate cancer or tuberculosis, in women with blood from the vagina (mensis, diseases of the uterus, ovaries).

Erythrocytes in urine are:

a) unchanged - containing hemoglobin, having the appearance of greenish-yellow discs, appear in diseases of the urinary tract: urolithiasis, acute cystitis, prostatic hypertrophy, tumors of the urinary tract;

b) modified or leached - hemoglobin-free, colorless, ring-shaped (in urine of low relative density) and wrinkled (in urine with high relative density), are characteristic of kidney pathology: acute glomerulonephritis, exacerbation of chronic glomerulonephritis, kidney tumors, kidney tuberculosis.

Allocate macrohematuria, when the urine is red or brownish red, and microhematuria, in which red blood cells in urine can only be determined by microscopic examination, recurrent and persistent, painful and painless, isolated and combined(with proteinuria, leukocyturia),

Also, hematuria is subdivided into renal(glomerular) and extrarenal(non-glomerular). With renal hematuria, erythrocytes enter the urine from the kidneys, with extrarenal hematuria they are mixed with it in the urinary tract.

Differential diagnostic signs of renal and extrarenal hematuria:

1. Pure blood is excreted from the urethra more often with bleeding from the bladder than from the kidneys, in which blood is mixed with urine.

2. The color of blood in renal hematuria is brownish-red, in extrarenal hematuria - bright red.

3. Blood clots usually indicate that blood comes from the bladder or pelvis.

4. Presence in urinary sediment leached, that is, erythrocytes deprived of hemoglobin, is observed with renal hematuria.

5. With insignificant hematuria (10-20 in the field of view), if the amount of protein is more than 1 g / l, then hematuria is most likely renal. On the contrary, when with significant hematuria (50-100 in the field of view) the protein is less than 1, the hematuria is extrarenal.

6. Undoubted evidence of the renal nature of hematuria is the presence in the urinary sediment erythrocyte casts.

7. With gross hematuria, a three-glass test is carried out to determine its nature.

Three-glass sample: the patient, when emptying the bladder, excretes urine sequentially into three vessels; with bleeding from the urethra, hematuria is greatest in the 1st portion; from the bladder - in 3 portions; with other sources of bleeding, red blood cells are distributed evenly in all three portions.

Renal hematuria

· Acute glomerulonephritis - which is one of the main symptoms of the disease. Macrohematuria (urine of the color of "meat slops) can be detected, there can only be microhematuria;

· Chronic glomerulonephritis - single erythrocytes are found in the field of view (they may not be at all). With exacerbation of chronic glomerulonephritis, hematuria appears or intensifies;

· Kidney infarction - characterized by sudden gross hematuria simultaneously with the appearance of pain in the lumbar region;

· Malignant neoplasms of the kidneys - for no reason, in the midst of complete health microhematuria appears in the absence of pain. Typically, its disappearance and appearance at various intervals (recurrent painless hematuria);

· Tuberculosis of the kidneys - microhematuria is found constantly. It is an early sign;

· Diseases with increased bleeding (hemophilia, acute leukemia, Werlhof's disease). In this case, there are bleeding from other organs;

· Severe infectious diseases (smallpox, scarlet fever, typhus, malaria) due to toxic damage to the vessels of the kidneys;

· Traumatic kidney injury;

· Nephrotic syndrome - erythrocytes in urine are not detected. At the same time, the presence of 1-2 red blood cells in the field of view does not exclude this diagnosis;

Stagnant kidneys - microhematuria is detected along with proteinuria;

· Significant physical exertion - minor microhematuria may appear along with transient proteinuria.

Extrarenal hematuria is detected in the following diseases:

Urolithiasis - hematuria is accompanied by a severe painful attack (recurrent painful hematuria);

Acute cystitis - blood appears at the end of the act of urination, since the blood that has settled at the bottom of the bladder is removed when it contracts at the end of the act of urination, the reason is also a significant decrease in intravesical pressure after emptying and a new flow of blood from the affected vessels of the mucous membrane;

· Acute pyelitis - there is an admixture of blood to the first drops of urine;

· Malignant neoplasms, polyps of the pelvis and bladder. Unlike hematuria in malignant renal lesions, hematuria in bladder cancer is constant, prolonged, persistent;

· Injuries, after medical procedures;

· With sepsis, typhus and other severe infectious pathology.

Give a clinical assessment of the appearance of casts in urine:

Excretion of cylinders with urine is called cylindruria. Cylindruria is one of the most important signs of kidney damage.

· Urinary cylinders are formed from protein coagulated in the tubules and urine formed elements and are casts of the renal tubules, have a cylindrical shape:

· Hyaline cylinders- protein formations, are detected already with moderate proteinuria (organic - in acute chronic glomerulonephritis, nephrotic syndrome and other kidney pathology, when albumin pass through the glomerular filter, and functional). Single hyaline casts appear in healthy individuals during physical overload, dehydration, in concentrated acidic urine;

· Waxy cylinders consist of the protein of hyaline casts, but more densely located; have a wax color characteristic of nephrotic syndrome of various origins;

· Granular cylinders- serve as a sign of organic kidney disease, are formed from disintegrated cells of the tubular epithelium, indicate degenerative processes in the tubules, are detected in nephrotic syndrome, pyelonephritis;

· Epithelial casts have a protein base, which is covered with adhered epithelial cells;

· Erythrocyte casts observed in acute and chronic glomerulonephritis.

The presence of epithelial, granular, waxy, erythrocytic casts in the urine indicates tubular damage, but there is no direct relationship between the degree of cylindruria and the severity of the renal process.

Bile pigments (bilirubin, biliverdin, etc.) are formed during the breakdown of hemoglobin of erythrocytes and appear in the urine with jaundice. Urine containing bile pigments is yellowish-brown or green in color (characteristic of jaundice).

Test for bilirubin with iodine solution (Rosin test)

Carefully lay a 1% alcoholic solution of iodine or Lugol's solution to 3 ml of urine. In the presence of bilirubin, a green ring forms at the interface between the two fluids. With normal urine, the negative test is on.

Gmelin test for bile acids

To 1 ml of concentrated nitric acid, carefully lay an equal volume of urine on the wall. In the presence of bile pigments, a green ring forms at the border of the layering.

8. Petenkofer's test for bile acids.

The reaction is based on the condensation of bile acids with oxymethylfurfurol, which is formed under the influence of concentrated sulfuric acid from sucrose. The condensation product has a red-violet color.

Place 1 ml of urine in a test tube, add 5 drops of 5% sucrose solution and carefully lay 1 ml of concentrated sulfuric acid on the tube wall. In the presence of bile acids, a red-violet ring is formed at the boundary of the layering.

9. Jaffe's test for urobilin.

Add a small portion of zinc chloride solution to 2 ml of urine. On shaking, a flocculent precipitate appears, which is dissolved in a concentrated ammonia solution (about 1 ml). Normally, a weak green fluorescence appears, pronounced in pathology.

10. Qualitative determination of indican in urine.

Indikan, a potassium or sodium salt of indoxylsulfuric acid, is found in normal urine in the form of traces. A lot of indican is found in the urine of herbivores, as well as in human urine with increased decay of proteins in the intestine, with constipation and intestinal obstruction.

Pour 4 ml of the test urine into a test tube and add an equal volume of sulfuric acid with stirring. Then add about 1 ml of chloroform, 1 - 2 drops of potassium permanganate solution, close with a stopper and turn over several times without shaking. Place the test tube in a rack and observe the intensity of the blue staining of the chloroform layer. 13. Solve situational tasks.

To be able to explain the principle of the method of determination and the clinical and diagnostic value of some biochemical parameters 1. Separation of serum proteins by paper electrophoresis and quantitative determination of protein fractions.

Separation and quantification of protein

fractions of blood serum by electrophoresis on paper.

The principle of the method. Electrophoresis is the movement of charged particles in a direct electric current field. The speed of movement of protein molecules in an electric field depends on the magnitude of the charge, molecular weight, pH, and ionic strength of the solution.

Serum proteins are placed on a strip of paper soaked in buffer solution through which a constant electric current is passed. At pH 8.6, serum proteins are negatively charged and, under the influence of an electric field, move to the anode.

Human serum contains various proteins. Using electrophoresis on paper, 5 fractions are isolated - albumin, α1-, α2-, β-, γ-globulins.

Clinical and diagnostic value. Many pathological conditions are accompanied by quantitative changes in the ratio of protein fractions of blood - dysproteinemia. A decrease in the content of the albumin fraction is characteristic of liver diseases due to a decrease in the protein-synthesizing function of hepatocytes. Hypoalbuminemia also accompanies kidney disease due to urinary protein loss. An increase in the content of α1- and α2-globulin fractions is observed under stress, the presence of inflammatory processes due to the "acute phase" proteins, with collagenoses and metastasis of malignant neoplasms. The fraction of β-globulins increases with hyperlipoproteinemia. The fraction of γ-globulins increases during immune reactions caused by viral and bacterial infections. A decrease in the γ-globulin fraction can occur in primary and secondary immunodeficiency.

Work order

1. The device for electrophoresis. The device consists of a rectifier that supplies a constant current of the required voltage and an electrophoresis chamber. The chamber itself consists of 2 baths; in one of them there is a fixed partition, where the platinum electrode (+ anode) is placed, and in the other there is a stainless steel electrode (- cathode). Between the baths filled with the appropriate buffer, there is a connecting bridge on which strips of special filter paper are placed.

2. Carrying out electrophoresis. Fill both baths of the chamber with a solution of Veronal buffer with a pH of 8.6. The buffer solution in the baths should be enough to cover the fixed partition, but be lower than the movable partitions.

Insert electrodes into baths. Cut out strips of the required size from the filter paper, depending on the size of the chamber (usually 4-6 cm wide) and with a simple pencil mark the place where the serum will be subsequently applied (start). Soak these strips in Veronal buffer. Insert the connecting bridge into the chamber baths. Place strips of paper on dry plates with tongs, immersing the ends of the strips in baths with buffer, and on the previously marked areas of paper apply serum 0.025-0.005 ml at a distance of 5-6 cm from the edge of the bridge. Serum is applied from the cathode side.

Figure 1. Schematic of a chamber for electrophoresis of proteins on paper:

1 stabilizer; 2-chamber for electrophoresis; 3-buffered solution; 4-supporting connecting bridge-electrode; 5-filter paper for electrophoresis.

After applying serum to paper strips, the chamber is sealed with a lid. On the lid of the chamber there is a locking clip, which is used to turn on the camera. The connected rectifier supplies the camera with a constant current of 2 to 4 mA at a constant voltage of 110-160V. Electrophoresis is carried out at a potential gradient of 3 to 8 V per 1 cm of the strip at room temperature. Good separation occurs in 18-20 hours.

3. Switching off the device and identifying protein fractions. Turn off the device. Remove the cameras and remove the paper strips from the device. Then each strip is placed in an oven for 20 minutes at a temperature of 1050C. In this case, the protein fractions are fixed on paper. Protein staining is carried out with a solution of bromophenol blue for 30 minutes, then the electrophoretograms are washed with a 2% solution of acetic acid. The obtained electropherograms are dried in air. Protein fractions are colored blue-green.

4. Quantification of protein fractions. Colored protein spots are excised, the dye is eluted with 0.01 N alkali solution. The color intensity of each fraction is determined colorimetrically using FEC.

The quantitative determination of protein fractions on an electrophoretogram can be established in two ways: by elution of paint and photocolorimetry and by a densitometric method.

albumin 55.4-65.9%

α1-globulins 3.4-4.7%

α2-globulins 5.5-9.5%

β-gdobulins 8.9-12.6%

γ-globulins 13-22.2%

Densitometric method. In a special apparatus (densitometer), a beam of light is passed through the electrophoretogram, the absorption of which depends on the optical density of the colored protein spots. The light passing through the electrophoretogram is captured by a photocell and turns into an electric current, the fluctuations of which are recorded on a paper sheet in the form of a curve, each peak of the curve corresponds to a certain protein fraction.

Figure 2. Electropherogram of human serum.

Urobilinogen is formed as a result of the metabolism of bilirubin and appears to be a bile pigment. This substance gives the urine a characteristic color. And if the presence of bilirubin in the urine is regarded by doctors as a pathology (bilirubinuria), then the presence of this substance indicates something else. If urobilinogen is found in urine, what does it mean? This question is of interest to many patients. Moderate content of it in urine is a variant of the norm. Well, if the norm is exceeded or underestimated, how to assess this? Let's figure it out in more detail.

Bile pigments

An important indicator when passing urine tests is bile pigments. An increased amount of urobilinogen in the interpretation of the analysis may indicate the cause of some diseases of the body. This substance is formed as a result of the breakdown of hemoglobin, as well as other proteins in the body that contain it. This pigment is contained in bile, and it gives it a yellow color.

Among the indicators of the analysis, the most valuable is bilirubin, as well as the products of its conversion, which, in turn, are formed in the intestine under the influence of microflora (bilirubinoids). To detect them, the urine is very carefully checked. Urobilinogen also plays an important role. The doctor must necessarily consider its significance, and if urobilinogen is detected in the urine, what this means, must be sure to explain to the patient. If necessary, send for additional examination.

Urobilinoids

Any healthy person has a certain amount of urobilinogens in the urine. After oxidation in urine, they are converted to urobilins. In order for urobilinogen to completely convert to urobilin, urine must stand in the light for at least a day. For this reason, the determination of urobilinogen in urine is carried out on fresh tests.

To determine the amount of urobilin, urine standing is examined. It has a yellowish tinge, whereas urobilinogen is colorless in urine. This explains the fact why, standing in the light, the urine darkens. These substances (urobilinoids) are derivatives of bilirubin, which, in turn, is excreted in the bile. In terms of their chemical composition, urobilinoids have a similar structure. If bilirubin has not reached the intestines, then these substances are not detected. This happens for a number of reasons: with hepatitis, blockage of the biliary tract, fistulas.

How are they formed?

Urobilinogen is formed from erythrocytes (up to 80%), to be more precise, from bilirubin, which, in turn, is synthesized from hemoglobin. In essence, urobilinogen is nothing more than a product of the utilization of erythrocytes. How is the process going? After serving the due date, the hemoglobin molecules must be disposed of. First, indirect bilirubin is synthesized from them; it enters the intestines with the flow of bile. Under the influence of microflora, bilirubin undergoes further transformations. Multiple complex biochemical reactions help form a number of intermediates. Some of them (mesobilinogen, stercobilinogen) are again absorbed into the bloodstream, something is excreted in the feces. The part that entered the bloodstream is re-captured by the liver cells. Urobilinogen is released again with bilirubin in the bile. A small part of the blood passes by the liver through hemorrhoidal anastomoses. Thus, some of the urobilinogen is released into the urine. For various reasons, the amount of it may be different in it. If urobilinogen is present in urine, what does this mean, we will consider further.

Norm

In a healthy person, the urine of urobilinogen contains a scanty amount, therefore, when determining it, tests show a negative result. Hence, it is clear that the numbers do not indicate urobilinogen in the urine (the rate of readings is 5-10 mg / l), but simply put the result "+" in the value. Weakly positive reaction - "+", "++" - positive and "+++" - sharply positive. Several conditions affect these indicators. If the level of urobilinogen is elevated, a diagnosis of urobilinuria is made.

When analyzing urine, it is very important to determine the level of urobilin. According to these indications, the doctor can judge how the urinary system works. The normal color of urine is slightly yellowish, transparent. If dehydration occurs in the body, the amount of water in the urine decreases sharply, and the urobilinogen becomes more concentrated. As a result, the urine becomes darker. Also, certain medications, various diets, alcoptonuria (hereditary disease) can also affect its color.

Increased performance. What do they mean?

As we found out, the urobilinogen indicator is normally negative - its amount in the urine is so negligible. Under what pathologies can the level of this indicator in the blood increase, in which case does urobilinuria occur? First of all, urobilinogen in urine is increased in chronic, acute liver pathologies, in those conditions when the destruction of erythrocytes occurs, the intestine does not function normally. Namely, when:

• cirrhosis, hepatitis of the liver;
• malignant or benign tumor;
• congestion in the liver;
• hemolytic anemia, in this condition there is a complete breakdown of erythrocytes (red blood cells);
• poisoning with chemicals, when the breakdown of erythrocytes also occurs, hemoglobin in this case appears freely in the blood plasma; this, in turn, increases the formation of bilirubin, and it is excreted in the bile (as we have already found out, urobilinogen is formed from bilirubin).

Also, the following factors affect the increase in the indicator:

An increase in urobilin, according to many doctors, is not an obvious pathology, but only indicates the possibility of its presence. So, in some conditions, when excess waste is released into the intestines (for example, with diarrhea), the kidneys receive an additional load, as a result, the presence of urobilinogen in the urine. This only confirms that the kidneys are doing their job.

Reasons for the increase

Summarize. What does urobilinogen show in urine? Either an excess of bilirubin production by the liver, or its slow utilization. Such symptoms appear with liver diseases (cirrhosis, hepatitis) or with hemolysis (the process of destruction of red blood cells).

What other reasons are there for the increase:

• severe pathological changes in the spleen;
• poisoning with poisons, toxins;
• blood transfusion of the inappropriate group, Rh factor;
• alcoholic liver damage;
• liver failure as a consequence of myocardial infarction;
• enterocolitis, ileitis;
• thrombosis, obstruction of the hepatic vein;
• insufficient fluid intake, excessive excretion.

Urobilinogen in urine during pregnancy

This pigment becomes highly concentrated when liver function is impaired. It can be caused by a hereditary predisposition or diseases such as cholestasis, hepatitis. If the urobilinogen in the urine of a pregnant woman is increased, then she darkens, acquires the color of dark beer.

Another reason for the increased concentration of urobilinogen in urine may be toxicosis, which contributes to increased fluid loss. In this case, the indicator fluctuates between 20 - 35 μmol / l.

Many pregnant women, receiving the result of the analysis, are interested in what such a high indicator means. Only an obstetrician-gynecologist can give such a consultation at the reception, perhaps he will send for additional examinations.

After carrying out diagnostic measures, the doctor will conclude whether the increased indicators indicate toxic damage to the body or the development of blood pathology.

If you are sure that the darkening of urine has nothing to do with fluid deficiency, increased fluid loss, or the use of any medications, then be sure to consult a specialist, dark urine is an alarming signal.

Urobilinogen in the urine of a child

The daily concentration of urobilinogen in the urine of an infant should not exceed 2 mg / l. If this figure is exceeded, the following diseases are suspected:

• hepatitis;
• cholelithiasis;
• cirrhotic liver damage;
• severe colitis;
• other infections.

To find out the true reason, you should familiarize yourself with the features of the developmental period of the baby. In infancy, the body mainly adapts to the outside world, the external environment. For newborns, jaundice is characteristic, it is caused by the breakdown of fetal hemoglobin (hereinafter referred to as red blood cells). As a result, an increased amount of urobilinogen is formed, and it is found in the urine. The phenomenon of jaundice at this age is temporary, therefore, increased urobilinogen in the urine is the norm for newborns.

Reduced urobilinogen

What if urobilinogen is absent in urine? What does this mean? Doctors do not consider the absence of urinobilinogen in urine as a valuable indicator, but this cannot be attributed to a variant of the norm either. If this substance is completely absent in the urine, but bilirubin is found, this may indicate blocked bile ducts or subhepatic jaundice. This is also a characteristic symptom of hepatitis A.

If bile does not enter the intestinal lumen, this also causes a decrease in urobilinogen in urine. The concentration of pigment can also decrease in large volumes of urine, in cases where fluid intake is exceeded (with some fruits).

What do we have to do?

Found urobilinogen in urine - what does it mean? What should be done in this case? The first tip is, don't panic. Nervous stress and negative emotions cause the manifestation of stagnation in the body. With increased levels of urobilinogen, it is imperative to consult a doctor in order to find out the true reasons, you need to undergo an additional examination.

Often those people who work at night do not sleep, their biological clock is disrupted. In this case, the reaction to the presence of urobilin bodies can be positive. In such a situation, the restoration of the regime can bring the body back to normal.

An active lifestyle, physical activity, water procedures help the body to get rid of toxins on time. A dairy-plant diet is also useful in such cases, which will help to improve the work of the intestines. Medicinal bitter herbs will not interfere in this case: wormwood, immortelle, elecampane, tansy, milk thistle. They will restore the body, help remove excess toxins from the intestines. The infusion is prepared as follows: one tablespoon is poured into 0.5 liters of boiling water and insisted for half an hour. Take ¼ glass before meals.

The question often arises: what are bile pigments in urine, and what do they indicate. There are many different substances in urine. Some of them should be normal in it, others appear only in case of any malfunctions in the human body.

Moreover, the danger of a situation is always assessed by the amount of such substances - the more there are, the worse the situation. The same is true for bile pigments.

What are bile pigments

Bile pigments are substances that make up bile. In color, they can be from yellow and transparent to blue-green. They are formed against the background of various oxidation processes in the liver and other organs of the body, as well as due to the breakdown of hemoglobin.

Normally, pigments should be excreted in the feces in the form of reduced bilirubin. In their properties, they resemble acids, metals and salts, against the background of which stones in the gallbladder are often formed.

An important parameter to study is the presence or absence of these pigments in urine. The kidneys are the filter organ. Accordingly, all metabolic products are excreted in the urine if their size is such that it passes through the organ's filter. Bile pigments are always present in urine, but in small quantities. It is they who set the color of the biofluid. It is believed that it is impossible to calculate the minimum using conventional methods, and there is no particular need for it.

If the urine begins to darken, then the doctor may suspect an increase in the concentration of these pigments. Moreover, the usual analysis carried out by professional laboratory assistants allows you to determine which pathology is developing. Studies prescribed for a particular disease help to track the course of pathology and the course of treatment.

Performing an analysis for bile pigments allows you to determine which area is affected, and what should be paid attention to first.

Pigments and their role in the human body

The rate of bile pigments is a guarantee that the body is working normally. The role of pigments in the human body is that they are products of metabolism and can indicate the onset of pathologies, while they have not yet given clear symptoms. There are several basic pigments.

Hemoglobin

The pigment hemoglobin is a respiratory blood pigment found in red blood cells. It is responsible for transporting oxygen from the lungs to the tissues.

In essence, it is not a bile pigment, but it is closely related to them, because they emerge from it. One of the main ones, which manifests itself against the background of the breakdown of hemoglobin, is bilirubin.

Bilirubin: features

In the urine of a healthy person, bilirubin is contained in small amounts, therefore, it is not determined during the analysis. Therefore, it is believed that it is absent in urine. If an increase in its amount begins, it is said that a person develops bilirubinuria.

Bilirubin can change the color of the liquid - to the so-called shade of beer. Bilirubin is produced by the breakdown of red blood cells. It cannot dissolve in water and is called free, which does not penetrate the kidney filter. Therefore, it does not appear in the urine, even if its amount is exceeded. But in the liver, such an element binds with glucuronic acid, as a result of which bound bilirubin is formed. But he just can be excreted in the urine. First, it passes through the ducts of the digestive organs, and then moves on.

If bound bilirubin begins to appear in the urine, the doctor may understand that some pathology of the liver or biliary tract is occurring in the human body, for example:

• viral hepatitis;
• cirrhosis;
• metastases from cancer of the digestive system.

Urobilinogen

Also, urobilinogen can be found in small amounts in urine. When urine is standing, it is oxidized and converted to urobilin, which is yellow. Therefore, with stagnation due to accumulated urobilin, the urine darkens. This also happens when dehydration is noted.

Normally, this substance should be contained in the analysis of no more than 17 μmol per liter. If this number grows, then such a pathological condition as urobilinogenuria develops.

Urobilinogen is the result of the interaction of bilirubin and enzymes of bacteria, cells of the intestinal mucous membranes, which enter here with bile. With the development of certain pathologies, the formation of such a substance can increase and intensify. In this case, there are situations when everything happens exactly the opposite, and the amount of pigment decreases.

An increase in urobilinogen in the urine indicates any diseases that occur against the background of the destruction and decay of red blood cells. These include:

• malaria;
• hemolytic jaundice;
• bleeding of internal organs;
• croupous pneumonia, etc.

It is not so difficult to recognize the presence of urobilinogen in your analyzes - it is indicated by crosses on the analysis card. If the reaction is weakly positive, there will be one cross. If it is sharply positive, 4 crosses will be written on the form.

Urobilin

Another pigment that is formed during the breakdown of hemoglobin. This pigment has an indirect relationship to bile. At the same time, he indicates how the human urine-excretory system works.

Biliverdin

Sometimes they can talk about the detection of such a pigment as biliverdin. It is the green pigment in bile. It is essentially an intermediate product of the breakdown of hemoglobin. When it breaks down, globin and iron are released. When enzymes act on it, it is again reduced to bilirubin.

Urinalysis and pigments

Many people may have a question: what is the analysis of pigments for. A change in their concentration speaks of pathology. And this is a quick enough way to understand if the body is functioning properly. Plus, with the help of such a study, it is possible to determine the developing complications that can develop against the background of the removed gallbladder, to see whether the stones from the bile excretion system were qualitatively eliminated.

Urine color and pigments

Pigments in urine can be recognized by its color. So, if they are not there or they are in extreme concentrations, it will be light. When urine darkens, they talk about problems in certain systems of the body.

Normal urine color and abnormal

Normal urine should be light yellow in color. It is also called straw. If it is too dark, closer to brown, doctors will prescribe an additional study for diseases of the liver and the digestive system in general. The indicator of urobilinogen should vary within 5-10 units. If this level is higher, additional manipulations will also be assigned, allowing you to determine exactly some deviations.

But there are situations when the level of this pigment decreases. In this case, they talk about the presence of an overlap of the bile ducts. They can be caused by:

• a blockage in the form of a stone or tumor;
• suprahepatic jaundice;
• intoxication;
• cirrhosis;
• constipation.

Rules for preparing for urine analysis

To get an accurate result, you need to correctly approach the delivery of material for research. Immediately after collection, the urine can be refrigerated for 2 hours. But this is in the event that there is no way to immediately go to the laboratory.

The morning portion of the material should be handed in, ideally, when nothing has yet been eaten or drunk. For a full study, 30-50 ml will be enough.

So that the result of urine analysis for bile pigments is not distorted, you should wash before taking the material. Women are advised to cover the vagina with a tampon so that the flora of the genital area does not get into the urine.

Biochemical analysis of urine as an additional diagnosis

If any excess indicators of bile pigments appear, an additional biochemical urine test may be prescribed. It will be more detailed and will show more accurate parameters, as well as additional substances that may be released in certain pathologies. Here, among the indicators, creatinine, potassium, calcium, protein, etc.

What diseases do these pigments in the urine indicate?

If malfunctions occur and pigments begin to appear or increase in the urine, doctors make a preliminary diagnosis. So, for example, in adults, the appearance of bilirubin in the urine indicates the development of:

• gallstones;
• various infections of the digestive system;
• poisoning;
• hepatitis;
• cirrhosis;
• tumors;
• complications against the background of a removed gallbladder;
• intestinal obstruction;
• malfunctions of the heart and vascular system;
• hypothyroidism. Against the background of physiological adaptation, the replacement of fetal hemoglobin is noted.

An increase in urobilin in adults appears when:

• certain pathologies of the liver;
• increased hemolysis of erythrocytes;
• pathologies of the gastrointestinal tract, which arise against the background of increased absorption of the breakdown products of hemoglobin, for example, constipation and obstruction.

Children may have their own reasons why urinalysis readings change. In infants, bilirubin may be elevated even in the norm - the systems are still adapting, the replacement of fetal hemoglobin is noted and is accompanied by the breakdown of red blood cells. Usually in children at this point, neonatal jaundice is diagnosed. Therefore, it is worth taking a closer look at how the situation develops. If the child accelerates the increase in bilirubin production, it is clear to the doctor that some pathology has begun, and measures should be taken urgently.

Normally, ketone bodies are absent in the general urine analysis.

Although in fact, 20-50 mg of ketone bodies (acetone, acetoacetic acid, beta-hydroxybutyric acid) are excreted in the urine per day, they are not detected in single portions. Therefore, it is believed that there should be no ketone bodies in the general urine analysis.

Interpreting Analysis

When ketone bodies are found in urine, two options are possible:

In the general analysis of urine, along with ketone bodies, sugar is found - with confidence, it is possible to diagnose diabetic acidosis, precoma or coma, depending on the corresponding symptoms.

In the general analysis of urine, only acetone is found, and there is no sugar - the cause of ketonuria is not diabetes. The cause of ketonuria in this case may be: acidosis associated with fasting (due to a decrease in sugar burning and fat mobilization); a diet rich in fat (ketogenic diet); acidosis associated with gastrointestinal disorders (vomiting, diarrhea), with severe toxicosis and poisoning, with febrile conditions.
^

5. Bile pigments in urine

Bile pigments in urine can produce bilirubin and urobilinogen. Normally, bilirubin is absent in the general analysis of urine; the content of urobilinogen is 5-10 mg / l.
^

a). Bilirubin

In fact, the urine of healthy people contains a minimal amount of bilirubin that cannot be detected by conventional quality tests. Therefore, it is believed that normal urine analysis should not contain bilirubin.

Bilirubin, the most important pigment in bile, is formed as a result of the breakdown of hemoglobin in the reticuloendothelial cells of the liver, spleen and bone marrow. Bilirubin is present in blood plasma in the form of two fractions: 1. Direct (bound or conjugated) bilirubin; 2. Indirect (free, unbound or unconjugated) bilirubin.

Normally, 75% of the total bilirubin in the blood is accounted for by indirect bilirubin and 25% by direct (bound) bilirubin. When hemoglobin breaks down, free bilirubin is initially formed, in blood plasma it is present mainly in the albumin-bilirubin complex. Further, the "albumin-bilirubin" complex is transported to the liver. In liver cells, free bilirubin binds to glucuronic acid. As a result of this process (conjugation), bound bilirubin is formed, which is excreted into the bile ducts and enters the intestines as part of bile.

In the intestine, under the influence of bacteria, bilirubin is converted into urobilinogen, then into stercobilin, which is excreted by feces. Part of the urobilinogen is reabsorbed into the bloodstream and transferred to the kidneys, where it is excreted in the urine (Fig. 3). Interpreting Analysis

Only direct bilirubin is excreted in the urine, the concentration of which is normally insignificant in the blood (from 0 to 6 μmol / l), because indirect bilirubin does not pass through the renal filter. Therefore, bilirubinuria is observed mainly with liver damage (hepatic jaundice) and disorders of the outflow of bile (subhepatic jaundice), when direct (bound) bilirubin rises in the blood. For hemolytic jaundice (suprahepatic jaundice), bilirubinemia is not typical.

Rice. 3. Ways of getting bilirubin and urobilinogen into urine.
^

v). Urobilinogen

Urobilinogen (or more precisely a group of urobilinogen bodies) is a bilirubin derivative. The formation of urobilinogen from direct bilirubin occurs in the upper intestine under the action of intestinal bacteria. Part of the urobilinogen is reabsorbed through the intestinal wall and is transported with the blood of the portal system to the liver, where it is completely broken down, while the urobilinogen does not enter the general bloodstream and, therefore, into the urine. Not absorbed urobilinogen is further exposed to intestinal bacteria, turning into stercobilinogen. A small part of stercobilinogen is absorbed and through the portal vein enters the liver, where it is broken down like urobilinogen. Part of the stercobilinogen is absorbed into the general bloodstream through the hemorrhoidal veins and excreted by the kidneys into the urine; the largest part in the lower parts of the large intestine is converted into stercobilin and excreted in the feces, being its normal pigment.

Interpreting Analysis

By itself, a positive reaction to urobilinogen is not very suitable for the purposes of differential diagnosis of jaundice, because can be observed with a variety of liver lesions (hepatitis, cirrhosis) and with diseases adjacent to the liver organs (with an attack of biliary or renal colic, cholecystitis, with enteritis, constipation, etc.). The reasons for the increase in urinary excretion of urobilinogen may be as follows:

Hemolytic anemia;

Intravascular hemolysis (incompatible blood transfusion, infections, sepsis);

Resorption of massive hematomas;

Increased production of urobilinogen in the gastrointestinal tract: enterocolitis

Liver dysfunction: chronic hepatitis, liver cirrhosis; toxic liver damage (alcohol, organic compounds, toxins in infection and sepsis), renal vein thrombosis

Urobilinogen is formed from direct bilirubin excreted in the bile in the small intestine. Therefore, the complete absence of urobilinogen serves as a reliable sign of the cessation of the flow of bile into the intestine, which confirms the diagnosis of subhepatic jaundice in cholelithiasis.
^

6 bile acids

Bile acids in urine appear in parenchymal liver pathology in varying degrees of severity: weakly positive (+), positive (++) or sharply positive (+++).

Interpreting Analysis

Their presence indicates a gross damage to the liver tissue, in which the bile formed in the liver cells, along with entering the biliary tract and the intestine, directly enters the bloodstream. The causes are acute and chronic hepatitis, cirrhosis of the liver, obstructive jaundice caused by blockage of the biliary tract. This indicator is used as an important criterion for the differential diagnosis of jaundice. Bile acids in urine can also be found in persons with liver damage without external signs of jaundice, so this analysis is important for those who suspect liver disease, but do not have jaundice of the skin.
^

7. Additional biochemical studies of urine

In addition to the above basic studies, in the general analysis of urine, additional ones can be carried out, the purpose of which is associated with the etiology of the disease and is determined by the attending physician. These analyzes include the following:
^

a). Ehrlich's diazoreaction

Diazoreaction is often positive with typhoid fever, starting from the first week of the disease; with typhus, measles, diphtheria, erysipelas, miliary tuberculosis, pulmonary tuberculosis (in this case it is considered unfavorable in prognostic terms).

Ehrlich's positive diazoreaction is also observed often with lymphogranulomatosis, somewhat less often with decompensated heart defects, hydrothorax, ascites, adhesive pericarditis, large exudative pleurisy, and croupous pneumonia.

Therefore, its diagnostic value is small. It has some value only if you suspect miliary tuberculosis, and especially typhoid fever and lymphogranulomatosis.
^

v). Diastasis in urine

Of all the enzymes found in the urine, only diastasis has a diagnostic value in clinical practice.

The urine of a healthy person contains diastase, but its amount should not exceed 64 units according to the Wolgemut method. With a greater amount of it (for example, 128 and more units), it should be assumed that the pancreas is affected.

However, in some cases, an increase in the content of diastase can be detected in the urine without damage to the pancreas, for example, in peritonitis, cholecystitis, etc. However, here, too, this is due to concomitant pancreatitis.
^

with). Indicanum in urine

Indikan or indoxyl sulfuric acid is always excreted in the urine of perfectly healthy people in an amount of no more than 0.005-0.02 g per day. It is formed in the small intestines during the decay of proteins (from the resulting tryptophan, which, under the influence of trypsin, turns into indole).

The increased content of indican in urine, called indicanuria, makes it possible to detect it using ordinary qualitative reactions.

The release of indican is observed with prolonged constipation, with intestinal diseases occurring with significant breakdown of protein (putrefactive and purulent processes in the intestine, abscesses, carcinomas, abscesses, etc.).

Allocation of indican to a sharp degree is one of the early symptoms of intestinal obstruction, and in cases of blockage of the small intestine, it occurs during the first days, while with obstruction of the large intestine, indicanuria is usually not detected within 2-3 days. However, this difference is far from reliable, since the diagnostic value of indicanuria is weakened by the fact that it is generally observed with constipation lasting more than 3-4 days.

It should also not be forgotten that a significant amount of indican in urine is observed in diseases such as diabetes mellitus, gout, Birmer's anemia, purulent exudative limited abscesses, gangrene, etc.
^

d). Nitrogen in urine

Under normal conditions, the total amount of nitrogen excreted by urine is 12-20 g, of which the largest part (85%) is urea nitrogen, 5% is ammonia nitrogen, 1.6% is uric acid, 0.2% is purine. bases, about 2% for creatinine and 0.5% for hippuric acid.

A decrease in the excretion of nitrogen in urine is observed with some metabolic disorders, fever, kidney and heart diseases, the formation of edema, exudates and transudates, severe diarrhea, vomiting, and alimentary dystrophy.

Its increase occurs with the absorption of exudates and transudates, febrile diseases, diabetes, chronic phosphorus poisoning.
^

e). Ammonia in urine

The daily amount of ammonia excreted in the urine ranges from 0.3-1.4 g.

An increase in the excretion of ammonia in the urine is observed in various processes accompanied by acidosis, febrile conditions, diabetes, as well as in liver diseases associated with a weakening of its urea-forming function, which is important.

To judge the degree of acidosis, you can use the indicator: ammonia nitrogen / total nitrogen x 100, which in healthy people ranges from 2.2-5.5; with acidosis, it rises significantly.

A decrease in the release of ammonia per day occurs in some diseases characterized by alkalosis (parathyroid and infantile tetany, epilepsy, significant phosphaturia), as well as when ingestion of alkalis.
^

f). Creatinine in urine

Normally, from 0.8 to 3.0 g of creatinine is excreted in the urine per day. Its amount increases with the predominance of meat food and with intense muscular work, feverish conditions, acute infections, diabetes mellitus and diabetes insipidus.

It decreases with kidney disease, muscle atrophy, after recovery from infections, in old age, with chronic nephritis, and anemia.
^

g). Urea in urine

Of all the solid substances excreted by urine per day, the first place belongs to urea. The urine of a healthy person contains 25-35 g of urea per day. At the same time, urea nitrogen ranges from 10-18 g, accounting for about 85-88% of the total total amount of urine nitrogen.

In humans, urea is the main end product of nitrogen metabolism. Its formation is closely related both to the processes of protein breakdown in the intestine, and to the function of the liver, which has the ability to form urea.

Therefore, the amount of urea excreted in the urine per day depends mainly on the amount of protein in the food.

It is also secreted in increased quantities and with increased breakdown of the protein of the body itself, namely, with increased muscle work, diabetes, fever.

On the contrary, the decrease in urea excretion decreases with fasting and, in particular, with alimentary dystrophy. In addition, a decrease in urea excretion is observed in diffuse parenchymal lesions of the liver due to a decrease in its urea-forming function. This includes diseases such as atrophic and hypertrophic cirrhosis of the liver, acute and subacute yellow atrophy, liver cancer. In addition, the amount of urea decreases in acute, less often chronic nephritis.
^

h). Uric acid in urine

Uric acid, being the end product of purine metabolism, is always excreted in the urine, but its amount is subject to significant fluctuations in the range from 0.2 to 1.5 g per day!

The amount of it in the urine increases with the consumption of foods rich in purines such as liver, kidneys, brains, etc.

Under pathological circumstances, the daily amount of uric acid increases during a gouty attack, with croupous pneumonia, resorption of exudates in primiparous women shortly before childbirth, leukemias and large leukocytosis, burns, epilepsy, chorea.

A decrease in the excretion of uric acid is observed in lead poisoning, after ingestion of potassium iodide, quinine, urotropine, and the introduction of atropine. It is also observed with progressive muscle atrophy.

The previously popular belief that the determination of uric acid is important for the recognition of gout is not always justified.
^

l). Chlorides in urine

Of the inorganic salts excreted in human urine, mainly chlorides deserve attention. With normal nutrition, about 50-60 g of solid substances are released in the urine of a healthy person per day, of which 8-18 g is sodium chloride.

Its excretion in the urine largely depends on the composition of the introduced food and is usually uneven. Immediately after a meal, the amount of chlorides in the urine decreases, because part of the chlorides in the body goes to the formation of hydrochloric acid of the secreted gastric juice in order to increase again after a while after absorption from the intestine during digestion.

Determination of chlorides in urine is of known importance in cases where a salt-free diet is carried out. In such cases, if there is no dietary disturbance on the part of patients or kitchen errors, the amount of chlorides in the urine very soon drops to low numbers - 1 - 2 g, or even less, per day.

Chloride levels usually decrease in kidney disease. In this case, sodium chloride is retained in the tissues very often at the same time as water, which leads to edema. The so-called dry retention of chlorides is also possible.

Most often, chlorides are retained in nephritis. The amount of chlorides also decreases with profuse vomiting and sweating. The amount of chlorides excreted in the urine per day decreases sharply at the height of lobar pneumonia. It is often diminished in cardiac decompensation, and the chloride content in nighttime urine is higher than in daytime, even with nocturia. In the transition to full compensation of the heart, chlorides in the daytime urine portion prevail over the nighttime.

An increase in the amount of excreted chlorides is observed during the absorption of exudates, during the period of disappearance of edema, with the resolution of croupous pneumonia, etc.