Grainy cylinders. Casts in urine - what are they: causes, types, photos

Urine casts are very small casts of the renal tubule cavity. The presence of these indicates some health problems. Cylindruria occurs due to insufficient filtration of the kidneys. As a rule, this is associated with some pathology.

They are detected during a general urinalysis (abbreviated as OAM). This test is recommended for absolutely all people who come to a medical facility. The CBC and complete blood count (abbreviated as CBC) help identify many of the patient’s health problems. Also, OAM and OAC are a standard procedure for a comprehensive examination.

Casts in the urine of a child

Urine normally has a slightly acidic reaction. The pH value should not exceed seven, the minimum value is five and a half. Cylinders form in the urine, which is acidic. In addition, TAM may show increased amounts of protein.

The process of formation of these microscopic bodies indicates the presence of kidney problems. Normally, casts can be contained in urine, but no more than two in the field of view.

Types and reasons

Casts in urine can be formed in several ways:

• protein;
• epithelial cells;
• red blood cells.

It is also very important to note that strong physical activity or a protein diet is the reason for the detection of single hyaline casts in the urine.

There are three groups of cylinders in total:

• hyaline;
• granular;
• waxy.

In this case, granular ones are divided into several types:

• erythrocyte;
• leukocyte;
• epithelial.

Hyaline

Hyaline casts in urine are the most common type. Externally they are transparent and homogeneous. The ends of the cylinders are rounded. It is very important to know that single (up to two) hyaline casts identified as a result of urine examination are a normal phenomenon for a healthy body. As mentioned earlier, the reason for this is physical activity and a protein diet. If more of them are found in the urine, then the reasons may be:

• jades;
• kidney tuberculosis;
• dehydration;
• pathologies of the cardiovascular system (cardiovascular system);
• liver diseases and so on.

Grainy

Granular casts in urine can be of two types:

• coarse-grained;
• fine-grained.

They appear as a result of damage to the kidney tubules. In this case, cellular elements disintegrate. If this type of cylinders is found in the urine, this indicates serious problems with the kidneys:

• glomerulonephritis;
• sclerotic changes;
• nephrolithiasis;
• development of malignant neoplasms in the kidneys and so on.

Waxy

Waxy casts in urine are completely different in appearance from other types, as they have a dense structure and look like wax. This is a very bad sign during research; this type of cylinders indicates that some tubules are completely atrophied and there is no urine flow in them.

Waxy casts may be detected during urine examination in the following cases:

• thermal;
• chronic severe form of glomerulonifritis;
• kidney amyloidosis;
• toxic kidney damage and so on.

Erythrocyte

Now briefly about red blood cell casts in urine. They are formed as follows: erythrocyte structures are layered or adhered to hyaline structures. The erythrocyte element can be distinguished from the structure of the cylinder itself. This helps recognize hematuria (that is, the presence of casts in the urine). There are cases when they are homogeneous. In this case, the reason may be:

• acute glomerulonephritis;
• vein thrombosis and so on.

The presence of red blood cells is always a pathology. Externally, this type has the following features:

• brownish color;
• edges may be torn;
• The cylinders are quite fragile.

To identify red blood cell casts, it is necessary to examine only fresh material. They talk about kidney and urinary tract diseases.

Leukocyte

Pathological casts in the urine can make it clear to the doctor what kind of pathological process is taking place in the patient’s urinary system. The laboratory technician who conducts the analysis must indicate what type of casts are found in the urine. Now briefly about another type - the leukocyte cylinder.

The detection of this form indicates serious diseases, among which are pyelonephritis, sepsis, lupus nephritis, and so on. They are formed as a result of the adhesion of leukocytes to the hyaline matrix. Leukocyte casts are quite difficult to detect, and when examining urine sediment, they can be confused with the epithelial type, which we will talk about right now.

Epithelial

An epithelial cast is a protein structure that is formed by compaction of epithelial cells. What causes them? The reason for their formation lies in the decay and dystrophic change of the tubules. The detection of this type indicates degenerative kidney damage.

They may appear in the urine of a patient with kidney failure who has recently had a transplant. Their detection indicates that the transplant is rejected by the body. However, this is not the only reason for their appearance in the urine. They appear when:

• acute tubular nephropathy;
• glomerulonephritis;
• terminal states and so on.

It is also important to note that the appearance of this type of cylinders for patients with glomerulonephritis is a very bad sign (damage to the tubular apparatus and the addition of secondary nephrotic syndrome).

Pigment

This species consists of blood pigments that are brown in color. Pigment cylinders are formed in several cases:

• when transfusion of incompatible blood;
• when exposed to toxic substances, and so on.

We remind you once again that all cylinders can only be identified in urine with an acidic reaction, since alkaline has a destructive effect on them. In urine with an alkaline reaction, they may not be detected at all or may be present, but in small quantities.

When examining sediment, do not forget that there may also be pseudo-cylinders formed by mucus or uric acid.

Depending on the type of renal pathology and the characteristics of its course, pathological cylinders in the urine are detected. Based on what type of cylinders is detected, the causative agent of the disease and the diagnosis are determined. The presence of such sediment is called cylindruria. This phenomenon requires a thorough study, since the cylinders originate from the renal parenchyma. In addition to pathological ones, there are casts that are present in the urine of completely healthy people and are not considered a sign of disease.

Causes of casts in urine

Identification of casts of any type in a general urine analysis indicates a serious disease of the urinary system.

As a result of some kidney diseases, protein particles, blood cells, and epithelium accumulate in the tubules of the parenchyma. From them, upon contact with the walls of the tubules, cylindrical casts are formed. The main factor in the occurrence of such sediment is the presence of protein, which indicates an inflammatory process in the kidneys and poor filtration. A urine test does not always show the presence of these particles in the urine in cases of obvious kidney disease, since the alkaline environment has a destructive effect on them. If an alkaline environment is determined, but cylinders are not identified, this does not mean that they do not exist. In an acidic environment, sediment from the cylinders is clearly visible.

By the type of cylinder, you can determine the cause of the disease of the genitourinary system.

Based on how many cylinders were detected in the urine and what type they belong to, a disease of the urinary system is determined and a functional disorder of the kidneys is diagnosed. Any type of cylinders indicates certain pathologies. The exception is hyaline casts that appear in the urine of a healthy person after physical overexertion.

Hyaline casts

Hyaline casts are a protein released from the blood plasma into the kidneys when they are functionally impaired. As it passes through the distal section, it takes on a cylindrical appearance, like tubules. This type of sediment is formed in an acidic environment. The number of cylinders depends on the level of protein. If its indicators are elevated, the concentration in the tubules is high, then hyaline casts are detected in large numbers. They are determined in a healthy person after physical work (the norm is no more than 2), as well as in pyelonephritis, glomerulonephritis, interstitial nephritis - diseases characterized by a high content of protein in the urine.

Grainy cylinders

The detection of granular casts in the patient’s urine indicates renal pathology.

These particles have a clear outline and are opaque. They are formed from a yellow mass, the basis of which is the degenerated, disintegrated, deformed epithelium of the kidney. They look like grains interspersed with fat that refract light, hence their name. Detected when used during osmic acid analysis. Granular casts in the urine are an indicator of pathologies such as glomerulonephritis of any form, amyloidosis, pyelonephritis.

Hyaline sediment can be detected in the absence of kidney pathologies.

Waxy

Waxy casts are formed from hyaline and granular, compacted and retained inside the tubules as a result of necrosis and thinning of their epithelial layer. They have no structure, visually similar to wax particles. The presence of this type of sediment in the urine indicates serious kidney disease, chronic pathologies and has an unfavorable prognosis.

Leukocyte

Leukocyte sediments in urine can be detected during infections and inflammatory processes in the kidneys.

This type of sediment is rarely found, mostly with pyelonephritis. It is based on protein and leukocytes. It confirms allergic nephritis, post-streptococcal acute glomerulonephritis, the presence of an inflammatory process or infection in the kidney. To prevent this species from being confused with epithelial cells, staining is used during the analysis.

Casts are microscopic impressions of the renal tubule cavity. The presence of casts in the urine is commonly called cylindruria. They are formed when the filtration activity of the kidneys is insufficient, caused by some pathology, and have a specific shape and size. Depending on the etiology and composition, they can serve as an indirect symptom of kidney pathology or a specific area of ​​the urinary tract.

Casts in urine - what does it mean?

Normally, urine is defined as a substance with a slightly acidic reaction - from 5.5 to 7.0 pH. Cylinders are formed and detected in urine with a pronounced acidic reaction. This is characterized by the presence of an increased amount of protein -.

With an alkaline reaction of urine, casts either do not form at all or quickly dissolve, which complicates testing. The alkaline reaction itself is a pathology and indicates kidney problems.

The process of formation of cylinders at the mouths of the renal tubules is directly related to disease and dysfunction of the kidneys. The norm allows the presence of only single protein (hyaline) cylindrical bodies - no more than 1-2 in the field of view. The presence of other types of cylindrical bodies during microscopic examination of urine is unacceptable.
In the video about what cylinders in urine mean:

Detection methods

Cylindruria is often detected during a general urinalysis. It is prescribed as a standard procedure for determining the patient’s health level for various diseases, as well as during a comprehensive examination.

For a specific examination, the following may be carried out:

• urine analysis according to Nechiporenko (more accurate and complete than a general analysis);
• collection of daily urine output;
• (to determine the excretory function of the kidneys);
• Reberg-Tareev test (velocity determination);
• clinical examination of urine for protein.

Analysis according to Nechiporenko is more often carried out in hospitals, as it gives more accurate results. In an outpatient setting, it is an additional research method and is prescribed when the general clinical urine analysis is insufficiently informative. The quantitative content of cylinders in 1 ml of urine along with sediment is revealed.

Daily urine output is collected for qualitative and quantitative urine testing. This allows you to determine how well your kidneys are functioning. The number of cylinders in the urine collected per day is measured, their chemical composition and physical parameters are determined, which contributes to a more accurate diagnosis.

The Zimnitsky test is performed not to determine the number of casts in the urine, but to determine the level of kidney function.

The specific gravity and density of urine are calculated, which suggests certain diseases:

• specific gravity from 1002 to 1008 - remission of chronic pyelonephritis, renal failure;
• a specific gravity over 1025 indicates severe acute pyelonephritis, dehydration, and uric acid diathesis in children.

The Reberg-Tareev test allows you to assess the excretory capacity of the kidneys. Used for differential diagnosis of kidney lesions of various etiologies, affecting functional features or tissues directly.

A clinical urine test for protein is performed to determine the level of proteinuria. In addition to this study, an ultrasound examination of the kidneys and bladder is often prescribed.

Types and reasons of education

The cylinders can be formed by: protein, desquamated epithelial cells of the renal tubules, erythrocytes. After physical exercise or during a diet with a predominance of animal (protein) foods, single cylindrical protein bodies (hyaline cylinders) can be detected in the urine.

Types of casts in urine

Hyaline

Hyaline casts are formed by a special protein produced by the epithelial cells of the kidney tubules. They are colorless, completely or semi-transparent, have rounded ends and are quite often detected by microscopic analysis of urine.

In men, hyaline casts may appear due to the large amount of meat products consumed in the diet. This increases the acidity of the urine and often leads to physiological proteinuria. In addition, hyaline cylindrical bodies appear after intense physical activity.

In the urine analysis of a pregnant woman, an increased content of hyaline casts most likely indicates a latent course of pyelonephritis or.

It may also indicate a violation of the filtration, concentration, and excretory functions of the kidneys, which is very typical for the last trimester of pregnancy.

In a child, an increased content of hyaline casts may indirectly indicate a number of diseases not directly related to the kidneys:

• polio;
• mumps (mumps);
• rubella;
• chickenpox;
• measles;
• whooping cough.

When the temperature rises to subfebrile (37-38°C) levels, the percentage of protein excretion increases, and with febrile (38.5-39°C) levels and insufficient drinking, dehydration of the child’s body may develop. Therefore, high temperature can also serve as a provoking factor for the formation of hyaline casts in the urine in children.

Hyaline casts in urine

Grainy

The composition of granular casts is very similar to hyaline casts: they are also based on protein produced by the tubular epithelium. In this case, disintegrated epithelial cells of the tubule cavity “stick” to the homogeneous surface of the hyaline bodies, forming a granular structure. They are determined in case of serious pathologies of the renal tubules, accompanied by their degenerative changes.

In children and pregnant women, the presence of granular casts most often indicates a hidden course of glomerulonephritis, in which damage occurs to the glomeruli of the kidneys, which are responsible for filtering the blood, the formation of primary urine and reverse osmosis.

In adults, the presence of granular casts may also indicate glomerulonephritis, but often in the course of further differential diagnosis other tubulopathies are determined:

• general damage to the tubular apparatus;
• increased tortuosity of the distal or proximal tubules;
• nephrolithiasis (kidney stone disease);
• polyuria - excretion of large amounts of fluid; characteristic of diabetic kidney damage.

Waxy

They are formed by protein denatured in the wide lumens of the renal tubules. Much shorter than hyaline, opaque, have a yellowish tint. The formation of waxy casts is associated with stagnation or poor urine flow.

Against the background of these conditions, the initially formed hyaline cylinders are first transformed into granular ones, but as they remain in the lumen of the tubule, more and more destroyed cells of the lining epithelium settle on their surface.

If waxy casts in the urine are elevated in all groups of patients, this indicates destructive changes in the epithelial layer of the renal tubules.

A frequently associated condition is nephrotic syndrome:

• severe proteinuria;
• massive swelling of the face and limbs;
• hypoproteinemia (decreased protein concentration in blood plasma);
• hyperlipidemia (increased cholesterol levels in the blood).

This condition is especially dangerous for pregnant women and children, so the detection of waxy casts in the urine requires immediate further examination in order to identify the primary pathology.

Waxy casts in urine

Pathological

By and large, all casts found in urine should be called pathological, since normally they should not exist. You can consider separately the presence of erythrocyte, leukocyte, and epithelial casts. For all groups of patients, especially pregnant women, young children and the elderly, the presence of the casts described below in the urine is a serious signal for a comprehensive examination.

Erythrocyte

Their origin is associated with the layering of red blood cells - erythrocytes - on the hyaline base. The appearance of red blood cell casts in the urine is often accompanied by the presence of blood impurities in the urine (hematuria) and indicates its renal origin.

The presence of erythrocyte cylindrical bodies is a sign of:

• renal vein thrombosis;
• exacerbations;
• acute glomerulonephritis;
• fornical bleeding;
• malignant neoplasm in the kidney cavity.

Leukocyte

Their appearance is associated with severe inflammatory processes, accompanied by significant pyuria (the presence of leukocytes in the urine). Most often, leukocyte casts are detected in the urine of patients with acute chronic pyelonephritis, complicated by purulent formations. Extremely rare in children.

Epithelial

The epithelial variety of cylinders is extremely rare.

Their appearance is associated with severe degenerative changes in the glomeruli and tubules of the kidney, which can be caused by:

• rejection;
• heavy metal poisoning (for example, lead);
• overdose of drugs (for example, salicylates).

Epithelial cylinders in urine

Pigment

Pigment cylinders are cylindrical bodies of rich yellow, brown, yellow-brown color, having a fine-grained structure.

For the most part they consist of hemoglobin, which has a free sediment during some pathological reactions of the body:

1. When transfusion of incompatible blood.
2. With myoglobinuria - under the influence of the myoglobin pigment, released during the pathological breakdown of muscle protein.
3. In case of poisoning with toxic substances.
4. For extensive injuries.

In pregnant women, in extremely rare cases, it can develop against the background of anemia caused by malnutrition. In children, the appearance of pigmented hemoglobin casts in the urine may be associated with an ultra rare disease - paroxysmal nocturnal hemoglobinuria Marchiafava-Micheli.

First of all, cylindruria indicates damage and degenerative changes in the parenchyma (body) of the kidney. It is generally accepted that the type of cylindrical bodies is not of particular importance, since if they are present, it is necessary to conduct a comprehensive examination and differential diagnosis.

Shown:

• Ultrasound examination of the kidneys and urinary tract.
• X-ray using a radiopaque contrast agent.
• or CT.

It is important to study the cylinders in order to determine the composition, since sometimes there are false cylindrical bodies - cylindroids formed from mucus. They may be present in the urine and do not indicate the presence of renal pathologies.

The term cylindruria refers to the release, along with urine, of “casts” of the distal sections of the cylindrical renal tubules. Casts in the urine usually form as a result of proteinuria. When the renal tubules have a lot of albumin and a more acidic environment than normal, protein elements begin to coagulate.

• hyaline;
• waxy (waxy);
• fibrin.

In the case when cellular elements are layered on the basic structure, the following are formed:

• granular;
• erythrocyte;
• leukocyte;
• epithelial.

Also, the detected cylinders may contain inclusions of hemoglobin, bilirubin, pigments, etc.

Normal urine tests in adults and children reveal exclusively single hyaline types or cylindroids.

To obtain the most reliable results you must:

1. Compliance with personal hygiene rules.
2. Collect material in a sterile container.
3. Exception:

• physical and emotional stress, at least 1-2 days before the test;
• acidifying (cranberries, meat, ascorbic acid), alkalizing (milk, fresh vegetables and fruits), urine-coloring (beets, carrots) products on the eve of tests.

1. If possible, you should stop taking medications.
2. The consumption of alcoholic beverages, strong coffee and tea is prohibited.
3. It is also recommended to avoid sexual intercourse twelve hours before collecting material.

What are hyaline casts and the reasons for their appearance?

The formation of hyaline elements occurs after the entry of primary urine into the tubules from the renal capsule only under the condition of an acidic reaction. When the pH shifts to the acidic side, they are easily destroyed under the influence of uropepsin, therefore, to obtain reliable results, urine analysis and examination of its sediment must be carried out immediately after collecting the material.

In appearance, hyaline cells are loose, pale with thinned contours, barely noticeable, almost transparent. Normally, their detection in single quantities is acceptable.
They cannot be detected in a strongly alkaline environment. This is due to the fact that albumins do not coagulate in alkaline pH, therefore, hyaline elements simply are not formed.

The reasons for this process are:

• nephritis (acute and chronic);
• nephropathy and severe toxicosis in pregnant women;
• glomerulonephritis, glomerulosclerosis;
• kidney tuberculosis;
• acute pyelonephritis;
• heavy physical overload;
• prolonged fever;
• dehydration after vomiting or diarrhea;
• condition after an epileptic seizure;
• arterial hypertension;
• heart defects and decompensated pathologies of the cardiovascular system (venous congestion);
• liver diseases;
• systemic lupus erythematosus.
• poisoning with salts of heavy metals.

What are granular species?

Coarse-grained, consisting of lipid grains or fine-grained structures. Appear as a result of damage to the tubular epithelium, renal parenchyma with the breakdown of cellular elements (epithelium, leukocytes, erythrocytes).

The detection of such casts and protein indicates a serious renal pathology: acute and chronic glomerulonephritis, sclerotic changes in the renal structures, nephrolithiasis, pyelonephritis, malignant neoplasms in the kidneys.

Also, granular elements can appear in disseminated forms of lupus erythematosus, severe viral infections, orthostatic proteinuria, arterial hypertension, heart disease, toxicosis during pregnancy. The drug cause of their increase may be long-term use of diuretics.

When do waxy (waxy) casts appear?

Unlike hyaline species, waxy elements are dense, long, matte, similar to wax clots.

Their detection serves as an extremely unfavorable diagnostic sign. This indicates that in some tubules there is practically no urine flow, that is, nephron atrophy has occurred due to severe damage to the renal parenchyma and degeneration of the tubular epithelium.

This picture can be observed in terminal (agonal) conditions, severe chronic glomerulonephritis, renal amyloidosis, nephrotic syndrome, severe systemic lupus erythematosus, toxic damage to kidney structures.

Erythrocyte

Appear as a result of layering (adhesion) to the hyaline structures of erythrocytes.

Sometimes the erythrocyte elements can be distinguished from the structure of the cylinders, this indicates hematuria from the urinary tract. In the case when they are absolutely homogeneous, the glomerular origin of hematuria should be suspected (acute glomerulonephritis, renal infarction, hepatic vein thrombosis, malignant hypertension).

Fibrin

Appears during hemorrhagic fever. Their detection indicates the culmination of the disease. After the patient begins to recover, their number in urine tests begins to decrease.

Leukocyte

They are detected with leukocyturia and are a marker of severe kidney infection (pyelonephritis, sepsis), nephritis, systemic diseases (lupus nephritis).

The formation of these elements occurs as a result of layering of leukocytes on the hyaline matrix. When examining sediment, it is very difficult to distinguish them from epithelial ones. Special staining is required for differential diagnosis.

Epithelial

Essentially, these are protein structures formed by compacted epithelial cells of the renal tubules. They arise as a result of decay and dystrophic changes in tubular segments and serve as a marker of degenerative kidney damage. If they are detected a few days after transplantation in patients with chronic renal failure, this indicates graft rejection.

Other reasons for their detection may be: acute tubular nephropathy, glomerulonephritis, sublimate necronephrosis, terminal conditions.

For patients with glomerulonephritis, this is a very unfavorable sign, indicating that the tubular apparatus is affected and secondary nephrotic syndrome has occurred.

Lipid (fat)

Found in lipoid degeneration of renal structures. The main causes may be nephrotic syndrome, sclerotic changes in the tubules, systemic diseases, and the malignant course of arterial hypertension.

Cylinders

Pale, long, ribbon-like structures of various shapes, formed by mucus. They may appear with catarrhal inflammation of the urinary tract, with the subsidence of nephritic and nephrotic syndromes, that is, after erythrocyte, hyaline, waxy, etc. disappear. cylinders.

Also, they are found in small quantities in normal tests.

Other types

Pigmented (most often hemoglobin) appear with hemoglobinuria or myoglobunuria. Mixed ones are found in terminal conditions and after long-term use of diuretics. Untrue, so-called saline, are a sediment of urates or phosphates in the form of cylinders.

Factors influencing the formation of cylinders

• presence of albumin;
• increase in relative density;
• decreased glomerular filtration rate;
• pH acidification;
• presence of cellular elements in urine tests;
• Bence Jones proteins, myoglobin.

Relative density

This parameter depends on the level of diuresis, the presence of organic compounds (glucose, protein, urea, salts), and the level of electrolytes (potassium, sodium, chlorine).

An increase in this parameter can be observed with severe dehydration, as a result of vomiting or diarrhea, increased sweating (loss of fluid and electrolytes) in hot climates, work in workshops (kidney diseases associated with working conditions), etc.

Also, an increase in relative density is detected in patients with diabetes mellitus, glomerulonephritis, and in pregnant women during toxicosis. Sometimes, the cause may be the abuse of meat products, combined with low fluid intake and heavy physical activity.

Change in pH

Normal pH values ​​for a healthy person should be slightly acidic. A change in the reaction of the environment can be caused by food preferences: meat products, cranberries and citrus fruits acidify, and dairy and vegetable dishes alkalize the pH.

Other reasons for its decline include:

• dehydration;
• prolonged fasting;
• decompensated diabetes mellitus;
• kidney tuberculosis;
• prolonged fever;
• excessive intake of vitamin C;
• hypokalemia.

Causes of proteinuria

Normally, protein molecules do not pass through the glomerular membrane - this is explained by their large size. However, in diseases associated with damage to renal structures, the loss of low molecular weight fractions (albumin) begins in the first stages of the disease. Further, as the disease progresses, medium- and large-molecular fractions can penetrate into the urine.

The causes of pathological loss can be:

• malignant neoplasms;
• glomerulonephritis with nephrotic syndrome;
• diseases of the cardiovascular system accompanied by hemodynamic disturbances;
• diabetic nephropathy;
• multiple myeloma;
• Fanconi syndrome;
• toxic kidney damage.

Normally, minor proteinuria is possible under severe physical and emotional stress. As a rule, these are transient changes that are not revealed in repeated studies.

Proteinuria may have a prerenal cause associated with tissue breakdown. Renal - associated with kidney disease. Postrenal loss of albumin occurs with urinary tract infections.

Cylinders are elements of cylindrical sediment (a kind of cast of renal tubules), consisting of protein or cells, and may also contain various inclusions (hemoglobin, bilirubin, pigments, sulfonamides). Based on their composition and appearance, there are several types of cylinders (hyaline, granular, erythrocyte, waxy, etc.).

Normally, renal epithelial cells secrete the so-called Tamm-Horsfall protein (absent in blood plasma), which is the basis of hyaline casts. Hyaline casts can be found in urine in all kidney diseases. Sometimes hyaline casts can be found in healthy people. As a pathological symptom, they acquire significance when they are constantly detected and in significant quantities, especially when erythrocytes and renal epithelium are superimposed on them.

Grainy cylinders are formed as a result of destruction of tubular epithelial cells. Their detection in a patient at rest and without fever indicates renal pathology.

Waxy cylinders are formed from compacted hyaline and granular cylinders in tubules with a wide lumen. They occur in severe kidney diseases with predominant damage and degeneration of the tubular epithelium, more often in chronic than in acute processes.

Red blood cell casts are formed when erythrocytes are layered on hyaline cylinders, leukocytes - leukocytes. The presence of red blood cell casts confirms the renal origin of hematuria.

Epithelial casts(rarely) formed when the tubular epithelium is detached. Occurs with severe degenerative changes in the tubules at the onset of acute diffuse glomerulonephritis, chronic glomerulonephritis. Their presence in a urine test a few days after surgery is a sign of rejection of the transplanted kidney.

Pigment (hemoglobin) casts are formed when pigments are included in the cylinder and are observed with myoglobinuria and hemoglobinuria.

Cylinders- long formations consisting of mucus. Single cylindroids are found in urine under normal conditions. A significant number of them occur during inflammatory processes of the mucous membrane of the urinary tract. They are often observed when the nephritic process subsides.

Reference values: hyaline cylinders – single, the rest – absent

Hyaline casts in urine:

• renal pathology (acute and chronic glomerulonephritis, pyelonephritis, kidney stones, renal tuberculosis, tumors);
• congestive heart failure;
• hyperthermic conditions;
• high blood pressure;
• taking diuretics.

Granular casts (nonspecific pathological symptom):

• glomerulonephoritis, pyelonephritis;
• diabetic nephropathy;
• viral infections;
• lead poisoning;
• fever.

Waxy cylinders:

• chronic renal failure;
• kidney amyloidosis;
• nephrotic syndrome.

Red blood cell casts (hematuria of renal origin):

• acute glomerulonephritis;
• kidney infarction;
• renal vein thrombosis;
• malignant hypertension.

Leukocyte casts (leukocyturia of renal origin):

• pyelonephritis;
• Lupus nephritis in systemic lupus erythematosus.

Epithelial casts (most rare):

• acute tubular necrosis;
• viral infection (for example, cytomegalovirus);
• poisoning with salts of heavy metals, ethylene glycol;
• overdose of salicylates;
• amyloidosis;
• kidney transplant rejection reaction.

M. V. Markin " General clinical tests of blood, urine, their indicators, reference values, changes in parameters in pathology", Novosibirsk, 2006