Hepatic transaminases. Causes of elevated alt and ast

The liver is an organ without nerve endings, working continuously. Therefore, liver problems often lead to disastrous results, to death, and are very difficult to treat at an advanced stage. Diseases often go unnoticed due to the difficulty of identifying hidden symptoms. Problems can be prevented and the course of the disease can be stopped in the early stages by receiving information about the condition of the liver in a timely manner. A regular detailed blood test, especially with a history burdened with concomitant diseases, is vital for many patients. Let's try to understand the mechanism of enzymes and the processes of formation of amino groups.

What are transaminases

Transaminases are called enzymes that accelerate and start the chemical reactions of metabolism in certain organs. They are involved in the formation of new amino acids, quickly transporting amino groups. Most of the processes for the formation of acids occurs in the liver and heart muscle. A number of symptoms are determined that suggest, long before the onset of a problem, possible deviations in the norm: weakness, lethargy, dull skin color, pain in the abdomen, swelling, intolerable pruritus that does not have an allergic component, skin jaundice, nausea.

Attention! In a healthy state, the indicators of transferase enzymes are not reflected in the result when conducting a biochemical blood test.

Blood sampling

Indicators of transaminases in the blood

The value of the liver enzyme is determined by the analysis of blood biochemistry.

Attention! For a reliable result, it is advisable to donate blood in the morning and on an empty stomach.

Biochemistry distinguishes two main indicators of aminotransferases:

1. Alat (alanine aminotransferase) - Enzyme produced in the liver, responsible for the transport of alanine.
2. AsAt (aspartate aminotransferase) - Enzyme produced in the heart muscle, transports aspartate.

For example, the ALT value for men is up to 45 units / l, and the female norm is up to 31 units / l. In newborns and children up to 5 days of life, this figure reaches 97 units / l. This is due to the fragile cell membranes and the constant rapid growth and development of organs.

Possible diseases

Diagnosis of diseases of the liver and heart begins with determining the amount of enzymes and a blood test for transaminase released into the blood due to cell destruction, since these enzymes are produced in these organs.

Important! An increase in the level of transaminase in the blood may indicate a predisposition to hepatitis of various etiologies.

An additional study of a detailed blood test will help stop the disease at an early stage and prevent deeper tissue damage. A systematic unreasonable increase in the index in the blood may indicate a predisposition to a tumor in the liver. You need to consult an oncologist.

Important! With a sharp increase in AsAt in the blood, it is necessary first of all to exclude acute myocardial infarction.

Violation of the enzyme metabolism provokes other problems with cardiac activity. possible deviations in the work of the atria, angina pectoris.

If the patient has burns or bone tissue disorders, problems with the gallbladder, a natural increase in AsAta in the blood is possible.

A huge role is played by genetic diseases, for example, Wilson-Konovalov disease, which is determined by the increased accumulation of copper in the body.

In addition, acquired diseases provoked by an unhealthy lifestyle, an insufficient amount of sports activity, a consequence of overeating, or a violation of other body systems.

Drugs that provoke the growth of the enzyme in the blood

The use of drugs that support the work of almost any body system can lead to a change in the balance of the enzyme in the blood. Particular attention should be paid to drugs that regulate cardiac activity and drugs focused on the regulation of liver function.

Important! Before taking an analysis with a detailed biochemical formula, it is necessary to warn the doctor about taking permanent drugs or to exclude drugs that affect the result.

How to distinguish heart disease from liver disease in enzyme analysis

Violation of the indicators of alanine aminotransferase and aspartate aminotransferase in itself indicates an imbalance and problems in the body. but how to quickly and reliably identify the problematic organ?

For this, the de Ritis coefficient was developed back in the 18th century. It is calculated in the case of a mutual exit of enzymes beyond the norm, otherwise the indicator does not make sense. This coefficient is a private ratio of two indices. The final indicator sets the interval of the norm (just when the calculation of the coefficient is useless) from 0.9 - 1.8. If the value obtained is higher than this interval, the patient has heart problems, if the indicator is less, then the liver does not work properly.

Indications for analysis

Important! Any deviations from the normal transaminase level in the blood of a biochemical blood test is a reason for an additional examination. It is necessary first of all to exclude damage to vital functions and organs.

Since transferase is produced only when cells are destroyed, a strong unreasonable increase in the indicator indicates necrotic processes in the body.

Symptom - nervousness and fatigue

The presence of chronic diseases with a history of heart or liver disorders is also a reason for regular monitoring of the state of enzymes in the blood. It is impossible to consider only some indicators from the entire biochemical series, without connection with others. For example, it is directly related to liver disorders and inflammatory processes. The human body is connected and shrouded in a single network of enzymes, secrets and works smoothly if everything is in balance.

Early diagnosis plays a very important role in the treatment of any disease. Today, doctors have learned to detect many diseases at an early stage of their development using transaminase studies. Transaminases - what is it and what function do they perform in our body. Why do doctors prescribe this analysis for various diseases and how it can be used to determine the presence of the disease.

What are transaminases

Transaminases are called special enzymes that are involved in the metabolism between cells. When a human organ is affected by a disease, its cells begin to die. Then transaminases get from the dead cells into the blood. If a large number of enzymes are found in the blood, then the disease is progressing and many cells of the organ have already died.

Of particular importance is the study of transaminases for the early diagnosis of liver diseases. It is they who in the first stages are absolutely asymptomatic and make themselves felt only when the treatment may no longer be effective. These diseases include chronic hepatitis, cirrhosis of the liver, cancer, etc. This blood test also reveals early damage to the heart.

To determine damage to the liver and heart, a blood test is performed for the content of AST and ALT enzymes in the blood. These markers can identify diseases at the earliest stages and greatly facilitate the treatment of the patient.

Today, experts call for this analysis to be carried out regularly, especially if you have reached the age of 40.

Liver diseases are getting younger day by day, if earlier the main incidence was observed in people who abuse alcohol, today malnutrition and poor ecology become the cause of liver diseases even in young people.

The heart of today's youth is also subjected to enormous stress. Bad habits, constant stress and fatty foods provoke the development of heart disease. One of the most dangerous heart diseases is myocardial infarction, and it can occur almost asymptomatically for several days.

Indicators of transaminases in the blood

In a healthy body, the process of transamination or metabolism between cells does not provoke an increase in enzymes in the blood. Transaminases are not released from healthy cells and cannot enter the bloodstream. An increase in these indicators occurs only in the case of cell death, which indicates the defeat of a particular organ.

A separate type of enzymes is localized in each human organ. So in the liver, the enzyme ALT is produced, and in the heart muscle - AST. By laboratory research, one or another type of transaminase is detected in the blood, which makes it possible to identify a damaged organ.

Thus, we can say that the norm of the content of transaminases in the blood is different for everyone.

However, there are average standards that help determine dangerous conditions when they are strongly exceeded. The table of approximate norms is as follows: the normal rate for adults and healthy men is ALT up to 40 units. and AST up to 31 units. per liter of blood. For women - ALT up to 32 units, AST up to 40 units. per liter of blood. With fluctuations in these norms, it can be suspected that liver or heart disease is progressing in the body.

Possible diseases

If you suspect a liver disease in the blood, the content of the liver enzyme ALT increases significantly. This indicator in the blood may indicate the following diseases:

• Liver necrosis. This disease is characterized by the death of liver cells and is irreversible. Determination of this disease by liver tests is possible only in the first stages of the disease, when there are still many cells and, when destroyed, they release the enzyme into the blood. In the later stages, there are so few healthy cells that their death no longer leads to a sharp increase in the enzyme in the blood.
• Hepatitis. This disease can be both viral and toxic. With viral hepatitis, infection occurs from the ingestion of the pathogen from the outside. With timely treatment, this type of hepatitis is successfully treated. Toxic hepatitis is caused by regular poisoning of the liver with alcohol, drugs or chemicals. With untimely treatment, hepatitis can go into the stage of cirrhosis.
• Acute hypoxia of the liver. This is a condition caused by a sharp decrease in blood pressure, which provokes the death of liver cells. This condition is extremely dangerous and the patient needs first aid within a few hours after the development of the pathology.

In addition to these dangerous diseases, an increase in ALT and AST in the blood can be caused by chronic cholecystitis, degeneration of liver tissues, alcoholic hepatosis, benign and malignant liver tumors, heart disease, diseases of the muscular system, burns, and injuries.

Drugs that cause an increase in the enzyme in the blood

Transaminases in the blood can increase not only in diseases, but also from long-term use of drugs that adversely affect liver function. Among the most dangerous drugs are:

• Antibiotics.
• Anabolics.
• Anti-inflammatory drugs.
• Hormones.
• Sulfonamides.
• Barbiturates.
• Immunosuppressants.

These drugs should be taken under the strict supervision of the attending physician with constant monitoring of liver function. Self-treatment with these drugs is unacceptable. With long-term treatment, it is necessary to take an enzyme analysis for the timely detection of liver damage.

How to distinguish heart disease from liver disease in enzyme analysis

Today in medicine there are concepts of the ratio of AST and. Normally, this ratio is 1/3, that is, one part of AST and three parts of ALT. According to the results of the analyzes, deviations from this norm can be seen. If the ratio changes in a smaller direction, it is safe to say that the pathology develops in the liver. If the ratio is increased, doctors diagnose heart disease. Only an experienced doctor can determine the ratio of these enzymes.

Indications for analysis

Most often, this analysis is prescribed to patients with the following symptoms:

• Chest pain with irregular heartbeat.
• Pain in the right hypochondrium.
• Chronic weakness and decreased ability to work.
• Yellowing of the skin.
• A significant increase in the tummy in an infant.
• Long-term treatment with dangerous drugs.
• Trauma to internal organs.
• Suspicion of toxic poisoning.
• As an assessment of the result of treatment.

Transominase - what is it? These are very important enzymes that help identify dangerous diseases in the early stages of development. This analysis appeared in medicine only a few decades ago, but, despite this, it is already used everywhere. After all, he can determine the disease earlier than ultrasound, x-rays and other diagnostic methods. Knowing the level of ALT and AST in the blood, it is possible to conduct timely treatment and prevent the death of the disease. If you are assigned this analysis, be sure to do it.

In contact with

Alanine aminotransferase and aspartate aminotransferase are endogenous enzymes and are significant markers in biochemical blood tests.

Although elevated levels of ALT do not unambiguously indicate the occurrence of health problems, nevertheless, both enzymes are simply not present in the blood in large volumes.

Yes, both ALT and AST levels can be elevated in liver disorders (such as cirrhosis or hepatitis), but other markers need to be carefully monitored as well. By the way, the level of ALT can be increased if myocardial infarction is diagnosed.

These enzymes are present in the tissues of many organs. Normally, aminotransferases are practically not found in the blood. The minimum activity of enzymes is due to natural regenerative processes in the body. An increase in the levels of ALT and AST are highly sensitive markers of damage to the tissues in which they are contained.

The method for determining aminotransferases in a biochemical blood test has found wide application in clinical practice due to its high sensitivity and specificity.

ASAT and ALT. Norm

Normally, aspartate aminotransferase does not exceed 31 U/l in women and 37 U/l in men. In newborns, the indicator should not exceed 70 IU / l.

AlAT in women normally does not exceed 35 U / l, and in men - 40 U / l.

Also, the results of the analysis can be presented in mol/h*L (from 0.1 to 0.68 for ALT and from 0.1 to 0.45 for AST).

What can affect transaminases

Distortion of the results of the analysis can lead to:

• the use of certain medications:
  • a nicotinic acid,
  • immunosuppressants,
  • choleretics,
  • hormonal birth control, etc.),
• obesity,
• pregnancy,
• hypodynamia or excessive physical activity.

How the study is done

For analysis, blood is taken from a vein. The results of an urgent study are provided within 1-2 hours. With standard diagnostics - within a day.

To obtain the most reliable results, you must:

• exclude the use of medicines a week before the test (if this is not possible, it is necessary to notify the doctor about the drugs taken);
• donate blood exclusively on an empty stomach;
• the day before the study, physical activity, smoking, alcohol, fatty and fried foods are excluded - two days before.

What can the analysis for ALaT and ASAT tell about

Selective tissue activity is characteristic of alanine aminotransferase and aspartate aminotransferase. If considered in
in descending order of the content of these enzymes in organs and tissues, the list will look like this:

• alanine aminotransferase: liver, kidneys, myocardium, muscles;
• aspartate aminotransferase: myocardium, liver, muscles, brain, kidneys.

That is, taking into account the tissue localization of enzymes, AST can be considered the most specific marker of myocardial damage, and ALT - the liver.

Attention! It is important to remember that when interpreting the tests, not only the degree of increase in enzymes is taken into account (it is directly dependent on the severity of the pathological process), but also the ratio of the levels of alanine aminotransferase and aspartate aminotransferase.

Comparison of enzyme activity makes it possible to assess the depth of damage to cellular structures. This is explained by the fact that AlAT is localized in the cytoplasm, and AST is localized in mitochondria and partially in the cytoplasm.

The ratio: aspartate aminotransferase / alanine aminotransferase, is called the de Ritis coefficient. For healthy people, the ratio is in the range from 0.91 to 1.75 and has no diagnostic value. The calculation of the ratio must be carried out when there is a deviation from the norm in the biochemical analysis.

For example, for liver diseases, alanine aminotransferase is considered a sensitive marker. In hepatitis, its activity can increase by more than 10 times, however, a pronounced increase in AsAT in such patients will indicate severe necrosis of liver cells.

If the level of aspartate aminotransferase significantly exceeds the ALT level, this may indicate the presence of pronounced fibrotic changes in the liver in people with chronic hepatitis. Also, such changes are observed in chronic alcoholism and drug-induced hepatitis.

In this regard, the de Ritis coefficient is of great clinical importance. In hepatitis of viral etiology, there is a decrease in the coefficient below 1 (the lower the indicator, the worse the prognosis of the disease). Indicators from one to two are typical for chronic liver diseases, accompanied by dystrophic changes. An increase in the value of the coefficient above 2 can be observed with necrosis of liver cells, as a rule, this is characteristic of alcoholic cirrhosis.

With myocardial infarction, the indicator is 2 or more.

Aspartate aminotransferase is elevated, what does it mean

Very important! Among the main reasons for the increase in aspartate aminotransferase, cardiac pathologies occupy the first place.

In acute myocardial infarction, the level of AST can increase 20 times from normal values. It should also be noted that changes in biochemical analyzes are noted even before the appearance of classical signs of a heart attack on the ECG.

In acute coronary insufficiency, an increase in aspartate aminotransferase is diagnosed within a day, then the value of the enzyme begins to decrease, and within a few days reaches normal values.

AsAT levels also increase in severe angina attacks, severe cardiac arrhythmias accompanied by attacks of tachyarrhythmia, acute rheumatic heart disease, pulmonary thrombosis, in patients after angiocardiography or cardiac surgery.

“Extracardiac” causes of an increase in aspartate aminotransferase are most often liver diseases of various etiologies. It can be:

• hepatitis:
  • alcoholic,
  • viral,
  • toxic origin,
• cirrhosis,
• malignant neoplasms (both with primary localization in the liver, and metastasizing to the hepatobiliary system),
• stagnation of bile (cholestasis associated with obstruction of the bile ducts),
• inflammation of the gallbladder (cholecystitis) and bile ducts (cholangitis).

Also, the reasons for the increase in aspartate aminotransferase can be acute and chronic pancreatitis, as well as purulent processes (abscesses and phlegmon) in the retroperitoneal tissue.

A moderate increase in enzymes is observed with increased physical exertion. In severe injuries, crush syndrome (destruction of skeletal muscles is observed), the levels of ALT and AST can increase many times over.

Rare causes of increased transaminase levels are hereditary muscular dystrophy, hemolysis, vasculitis, and systemic connective tissue diseases, accompanied by diffuse changes in the liver and / or myocardial damage.

Alanine aminotransferase is elevated, what does it mean

ALT is a specific and sensitive marker of diseases of the hepatobiliary system, therefore, its increase is most often
seen with:

• acute hepatitis (the higher ALT, the more pronounced cell destruction, and the combination with high AST indicates severe necrosis);
• obstructive jaundice (blockage of the bile ducts in cholelithiasis, giardiasis and obstruction by metastasis or tumor);
• fatty degeneration.

Important. You should know that in alcoholic cirrhosis, the increase in alanine aminotransferase significantly exceeds its increase in malignant tumors in the initial stages.

Other reasons for changes in analyzes can be acute pancreatitis, extensive burns, shocks (traumatic, hypovolemic, cardiogenic), myodystrophy, severe blood diseases, viral infections, constant nutritional errors (abuse of fried, fatty, spicy foods), severe physical and emotional overload .

Increased transaminases in women

Attention! Aminotransferases may increase in the first trimester of pregnancy, which is normal.

A pronounced increase in transaminases in the third trimester is a poor prognostic sign and indicates the development of severe preeclampsia.

High values ​​of alanine aminotransferase and aspartate aminotransferase in combination with a sharp rise in uric acid and alkaline phosphatase can be observed in eclampsia, accompanied by damage to the filtration apparatus of the kidneys.

Specific reasons for the increase in ALT and AST

Amoebic invasions, as a rule, manifest themselves as amoebic dysentery, however, extraintestinal manifestations are also encountered - fatty degeneration of the liver, liver abscess, amoebic metastases to the brain, pericardium, etc. The onset of the disease is manifested by pain in the abdomen, diarrhea with an admixture of blood and mucus, in the presence of a focus in the liver, alkaline phosphatase, ALT and AST increase.

In giardiasis, a pronounced increase in transaminases is observed when bile ducts are obstructed by Giardia.

What to do if transaminases are elevated

Attention. It is important to understand that an increase in ALT and AST is not an independent diagnosis.

This is a reflection of the pathological processes occurring in the body. To prescribe the correct treatment, it is necessary to undergo a complete examination and identify the cause of the change in the analyzes.

The selection of medicines and the preparation of a treatment regimen should be handled by a qualified specialist.

On the form of the results of a biochemical blood test, there are sub-items of “transaminase” - ALT (AlAt) and AST (AsAt), but do you know what it is, what these indicators are normal and what their deviations from the normal level mean?

Consider possible disorders in the body that can be detected due to these indicators of biochemistry.

The transamination reaction is the process of transferring an amino group from an amino acid molecule to an alpha-keto acid molecule. Free ammonia is not formed during the reaction.

Transamination is link between carbohydrate and nitrogen metabolism. It occurs with the participation of aminotransferase enzymes (transaminases).

Such enzymes are named after the amino acid involved in a particular reaction. Transamination of alanine is possible with the participation of alanine aminotransferase (AlAT), aspartic acid transaminates with the help of aspartate aminotransferase (AST) in the blood.

Norm of ALT and AST in adults and children

The level of aminotransferases in human blood is determined using a biochemical study. For correct results analysis should be carried out in the morning on an empty stomach.

At least 8 hours must have elapsed since the last meal. For research, venous blood is used.

The norm of ALT (ALT) and AsAt (AST) in the absence of pathological processes in the blood women, men and children are fundamentally different:

• children under 9 years old - AlAT up to 50 U / l, AsAT up to 140 U / l;
• children over 9 years old - AlAT up to 50 U / l, AsAT up to 55 U / l.
• men - ALT up to 45 U/l, AST up to 47 U/l;
• women - AlAT and AsAT up to 31 U / l;

Causes of level changes in biochemistry

Cytolysis (cell death) causes an increase in the number of transamination catalysts in the bloodstream. it possible with the following disorders in the body:

• heart diseases;
• severe poisoning;
• burns;
• infections;
• liver dysfunction;
• severe injuries;
• tumors;
• operations.

Increased performance: what does it mean for diagnosing cardiopathologies

Aminotransferases - myocardial infarction markers. An increase in their number indicates the heart muscle and the release of these enzymes from damaged cells.

Biochemical analysis, namely the determination of the level of alanine aminotransferase, aspartate aminotransferase and creatine kinase, allows you to determine the severity of the disease and the time from the onset of symptoms to the time of diagnosis.

With myocardial infarction, the following changes occur in the body, which reflected in laboratory data:

1. After an ischemic attack, the amount of creatine kinase in the blood immediately increases. This enzyme is determined only if the analysis is carried out immediately after the attack. The numbers quickly return to their original values.
2. The next stage is the growth of ASAT. Aspartate transaminase is most active in the heart muscle, therefore it is the main marker of myocardial infarction.
3. ALT rises last. Transamination enzymes increase on the second or third day from the onset of the disease. The values ​​exceed the norm by several times. In especially severe cases, the figure can be 20 times higher than normal numbers.

In addition to the enzymes mentioned above, ischemic cells secrete lactate dehydrogenase into the blood. The determination of this enzyme may serve as an additional factor in the diagnosis of the lesion and subsequent treatment.

In addition to myocardial infarction, the destruction of cardiomyocytes also occurs in heart failure, myocarditis, rheumatic heart disease, and some other diseases. This also contributes to an increase in the number of transferases in the bloodstream.

Other diseases in which the content is increased

If aspartate aminotransferase is considered a cardiac marker, then alanine aminotransferase has highest concentration in liver tissue. The growth of these indicators may indicate a number of injuries in the internal organs.

In various diseases, the ratio of aminotransferases to each other changes. The ratio of activity of a cardiac marker to a liver marker is called "de Ritis coefficient". With cardiac pathologies, the value of the coefficient increases, and with changes in the liver, it decreases. But at the same time, both values ​​​​are above the norm.

Enzymes, in addition to diseases of the cardiovascular system, increased in such pathologies:

• Severe liver diseases - cancer, fatty hepatosis, cirrhosis.
• mechanical jaundice.
• Hepatitis of various origins. An increase in alanine aminotransferase often occurs even before the onset of symptoms of the disease. In a biochemical analysis, it also determines an increase in the level of bilirubin. Aspartate aminotransferase increased to a lesser extent.
• cholestasis.
• Acute pancreatitis. The level of alanine aminotransferase increases with the appearance of an inflammatory process in the pancreas. In chronic pancreatitis, a uniform increase in both enzymes is determined.
• Muscle injuries, extensive burns.

The level of transaminases also increases with some pathologies of other internal organs. But in these cases, the indicators are not clinically significant.

When the quantity is not high, but low

Decreased transamination enzymes are rare. But for some pathologies AST may fall below 15 U/L and ALT below 5 U/L. Such indicators indicate the following violations:

• severe cirrhosis;
• liver necrosis;
• pyridoxine deficiency, for example, in alcoholics;
• decrease in the number of active hepatocytes;
• uremia;
• in patients on hemodialysis.

Aminotransferases are clinically significant enzymes. Their increase in the blood allows diagnose pathologies of internal organs even before the onset of severe symptoms. In order to bring the indicators to the ideal, no special treatment or diet is required. Transaminases return to the original amount on their own, as soon as the cause that causes cell death is eliminated.

A biochemical blood test, or simply blood biochemistry, is one of the methods of laboratory diagnostics, carried out on an outpatient basis and in a hospital. This study is indicated both for the diagnosis of various diseases, and for preventive purposes, in order to prevent one or another pathology in time. For the reliability of the results, all biochemical blood tests are taken in a medical institution from a vein on an empty stomach with the preliminary exclusion of stress, physical activity, fatty foods and alcohol.

It is measured in millimoles per liter (mmol/L). The normal level of glycemia is in the numerical range from 3.3 to 5.5. An increase in blood sugar above an acceptable level is called hyperglycemia. This condition is noted in diabetes mellitus, but not only.

Hyperglycemia is observed with injuries, serious illnesses, sepsis, stress, hormonal imbalance. Blood sugar rises with tumors of the adrenal and pituitary glands.

Hypoglycemia is the reverse state with a decrease in plasma glucose. The most common cause is an overdose of insulin and hypoglycemic drugs in diabetics.

In addition, blood sugar decreases with general exhaustion of the body, incl. and due to starvation. Hypoglycemia can occur with adrenal insufficiency, certain diseases of the pituitary gland, and tumors of the pancreas. Often, blood sugar is reduced in people who abuse alcohol. It should be noted that hypoglycemia poses a greater threat to the life of the patient than hyperglycemia.

2. Protein and its fractions.

Proteins or proteins are contained in the blood plasma in the amount of 65-85 g / l (grams per liter). In clinical practice, most often there is a decrease in protein below an acceptable level - hypoproteinemia.

This condition may be due to insufficient intake of protein from food, massive burns, severe infectious diseases, thyroid pathology, sepsis, liver damage and diseases of the gastrointestinal tract.

An increase in protein (hyperproteinemia) is less common. Most often it is relative and is caused by dehydration of the body and thickening of the blood, when the specific gravity of the dry residue, incl. and protein, increases. But there are more serious reasons - blood diseases, cirrhosis of the liver, tumors of the hematopoietic organs.

However, the total protein content says little. Of great diagnostic significance is the level of protein fractions - albumin and globulins. Albumins have a lower molecular weight and are contained in a larger amount - approximately 60-65% of the total protein. In globulins, the opposite is true - they weigh more, and their level is 30% of all proteins. Although globulins are heterogeneous - alpha, beta and gamma globulins are isolated.

The ratio of albumins and globulins is displayed in the coefficient of the same name, which normally ranges from 1.5 to 2.5. The aforementioned decrease in protein is mainly due to albumin, while the relative content of globulins increases. Accordingly, the albumin-globulin coefficient decreases. Increasing this coefficient has no practical significance.

3. Bilirubin.

Our erythrocytes are not eternal, and after a while (3-4 months) they are destroyed. Bilirubin is a breakdown product of hemoglobin found in red blood cells. Normally, bilirubin is contained in the blood in an amount of 8.5 -20.5 µmol / l. (micromoles per litre). This is total bilirubin, which is heterogeneous and is presented in two fractions - direct and indirect bilirubin.

Formed immediately after the breakdown of hemoglobin, bilirubin has a toxic effect on organs and tissues. This is free or direct bilirubin, which is always contained in the blood plasma, but in an amount not exceeding 17.1 μmol / l.

Further, indirect, toxic, bilirubin binds in the liver with glucuronic acid into a relatively harmless compound - direct or conjugated bilirubin, which is excreted in the bile into the small intestine. The content of the direct fraction is approximately 25% of the total amount of bilirubin - somewhere at the level of 4-5 µmol / l.

In various diseases, various fractions of bilirubin increase. With massive destruction of red blood cells (hemolysis) due to infectious diseases, poisoning, snake bites, direct bilirubin increases. The same indicator is increased in liver diseases, hepatitis. Indirect bilirubin increases due to mechanical obstruction of the outflow of bile - with gallstone disease, cancer of the gallbladder and pancreas. It is noteworthy that an increase in the level of bilirubin can even be determined visually by the characteristic icteric coloration of the skin and sclera.

4. Transaminases.

Transaminases or aminotransferases are enzymes that provide metabolism within the cell. In the course of biochemical studies, the level of two transaminases is determined - aspartate aminotransferase (AST, AsAt) and alanine aminotransferase (ALT, AlAt). Since aminotransferases are intracellular enzymes, their content in blood plasma is low. The level of AST is in the range of 0.1 - 0.68 µmol / mlh (micromoles per milliliter per hour), while in ALT this indicator is 0.1 - 0.45.

The increase in transaminases is due to the so-called. cytolysis syndrome - massive cell death. As a rule, this syndrome is caused by myocardial infarction, liver disease or severe poisoning, leading to the destruction of a large number of liver cells. Moreover, hepatic pathology is accompanied by a predominant increase in ALT, and in myocardial infarction, an increase in AST is mainly recorded.

In addition to the above conditions, an increase in transaminases is noted in severe injuries, burns, infectious and tumor processes, after extensive surgical interventions. Some laboratories may display aminotransferase levels in other units - units per liter (IU/L) or international units (IU). For women, the numerical value of this indicator should not exceed 30, and for men - 40.

5. Urea.

In our body, the processes of protein synthesis and breakdown are constantly taking place. In addition, part of the protein that comes with food undergoes decay in the intestines. And one of the products of protein breakdown is ammonia. This is a very highly toxic compound - even in small quantities it has a detrimental effect on organs and tissues, and primarily on the brain.

To prevent this from happening, ammonia is delivered with the blood stream to the liver, where, in the course of complex biochemical reactions, it is transformed into a harmless non-toxic compound - urea. Further, urea is delivered by blood to the kidneys, where it is excreted in the urine. However, a small amount of this compound is reabsorbed (reabsorbed) in the kidneys.

It is this amount of reabsorbed urea that determines its content in the blood plasma, which averages 2.4 - 8.3 mmol / l. True, this value may vary slightly depending on age - in children, the urea content is slightly lower, and in the elderly and old people it is higher. The high content of urea is mainly due to violations of the excretory function of the kidneys and renal failure, when the excretion of urea in the urine is impaired. This can also lead to heart failure, when blood flow to the kidneys is reduced.

Another reason for high urea is increased protein breakdown during injuries, burns, severe infections, and gastrointestinal bleeding. Sometimes a moderate increase in urea can be observed in the nome - after physical exertion and eating a large amount of vegetable and animal protein (meat, legumes). In some cases, there is a relatively high urea due to dehydration and thickening of the blood. Reduced urea in diseases of the liver and intestines. In the first case, its synthesis from ammonia is disrupted, and in the second, the absorption of food proteins is reduced. Low urea can be observed in vegetarians.

6. Creatinine.

This substance, like urea, is a product of protein metabolism and is also excreted by the kidneys. Creatinine is a product of metabolic processes occurring in skeletal muscles, and to a lesser extent in the brain. Accordingly, its level will depend on the condition of the kidneys and muscles. Normal creatinine levels in men are 57-93 µmol/l in women and 80-115 µmol/l in men. This difference is due to the unequal degree of muscle development in both sexes.

Elevated creatinine is observed in renal failure, severe injuries with muscle damage, with increased thyroid function, after the use of certain anti-inflammatory and antibacterial agents. Moderately high creatinine is found in athletes.

7. Amylase.

This enzyme is produced by the pancreas and, to a lesser extent, by the salivary glands. Under the action of amylase, starch and other high molecular weight carbohydrates are broken down into low molecular weight sugars. Most of the amylase is found in the glandular tissue of the pancreas and salivary glands, and in the blood plasma it is contained in the range of 25 - 100 IU / l.

An increase in amylase is a hallmark of acute pancreatitis, an inflammation of the pancreas. The level of this enzyme may be high due to blockage of the pancreatic duct by a stone or tumor. Amylase is elevated in mumps in children, which is commonly called mumps.

With further progression of pancreatitis, pancreatic insufficiency develops, which leads to a decrease in amylase activity. The low content of this enzyme is detected in the destruction of the pancreas (pancreatic necrosis) due to alcohol abuse.

8. Cholesterol.

Almost everyone has heard about it, but few people know what it is. Cholesterol is a substance formed in the liver and intestines, a product of protein and fat metabolism, belonging to the so-called. lipoproteins. Part of the cholesterol comes to us with food, mainly of animal origin. For many, cholesterol is associated with plaques that clog blood vessels and cause a heart attack or stroke. But not everything is so simple.

Lipoproteins come in high density (HDL), low and very low density (LDL, VLDL). HDL is part of cell membranes, participates in metabolic processes with the formation of many biologically active substances, incl. and sex hormones. But compounds with low and very low density are responsible for the development of atherosclerosis and related disorders.

9. Ions.

All trace elements in blood plasma are in ionized form and are involved in mineral metabolism. The most clinically important among them are:

• Na (sodium) - 135-145 mmol / l
• K (potassium) - 3.4-5.3 mmol / l
• Ca (calcium) - 2.23-2.57 mmol / l
• Fe (iron) - 9.0-31.3 µmol / l
• Mg (magnesium) - 0.65-1.1 mmol / l
• Cu (copper) - 11.0 - 24.3 mmol / l
• Cl (chlorine) - 77 - 87 mmol / l
• P (phosphorus) - 0.646-1.292 mmol / l

The reasons leading to a change in the content of these microelements are as numerous as the microelements themselves. This can be increased excretion of fluid in the urine, profuse vomiting and diarrhea, severe infections and lesions of the gastrointestinal tract - anything. Any pathological process in the body to some extent leads to ionic imbalance.

10. Conclusion.

The values ​​indicated in this article may vary slightly in various sources and reference publications. Only the most clinically significant studies are given, but in general, a biochemical blood test has several dozen indicators.

However, it is technically difficult and impractical to determine all the quantities in each specific case. The choice of certain biochemical parameters for laboratory diagnosis is determined by the doctor, depending on the disease. In addition, on the basis of the identified violations alone, it is almost never possible to make a correct diagnosis. A biochemical blood test is valuable only in combination with other methods of laboratory and instrumental diagnostics.

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