Lactate dehydrogenase (LDH) (venous blood). Lactate dehydrogenase (LDH) in a biochemical blood test: what is it, norms by age, what does an increase and decrease in the level of the enzyme Lactate dehydrogenase mean, what does it show

It is important to consider that lactate dehydrogenase may be elevated in women during pregnancy, in professional athletes and newborn babies. In old age, there is also an increase in indicators as a result of changes in the body.

Symptoms and signs of elevated values

The increase in LDH levels alone not accompanied by specific symptoms. Depending on the reason for the change in indicators, patients may experience pain in the heart, changes in blood pressure and pulse, headache, weakness, drowsiness, convulsions, decreased performance, and increased body temperature.

Dangers and Consequences

Significant increase in LGD indicates the presence of a pathological process in the human body. Lack of treatment or late diagnosis of the disease can lead to unpleasant consequences for the patient. Existing diseases can become severe and chronic, increasing the risk of strokes, heart attacks, and liver pathologies.

As already mentioned, this is an excellent marker for diagnosing various problems in the body. But what is an LDH biochemical test? This is a blood test that can be used to determine how much lactate dehydrogenase is in the blood. When does such an analysis become necessary?

Before the analysis is carried out, the patient must prepare for it. Your doctor will likely advise you not to take certain medications because they may interfere with the accuracy of your LDH results. We have already determined what it is. However, what medications should not be taken three days before the test?

A biochemical blood test for LDH does not require any special preparation. Like all many other examinations, it should be carried out in the morning on an empty stomach. As far as additional concerns and precautions are concerned, nothing is required. Normal meals are allowed, as always. Physical activity is also allowed, only if you do not overdo it.

In order to conduct a biochemical blood test, it is necessary to take 5-10 ml of blood from a vein on the elbow. In the process of studying the composition of blood, its composition, quantity and specific gravity of all constituent elements are revealed. All the results of this study and their interpretation are entered into special forms, which list the blood components and their quantitative content.

Then, based on the data obtained in the analysis, the doctor will be able to make the most accurate diagnosis, since the results obtained are compared with established standards for relatively healthy human donors. A blood test, or rather the resulting values, can vary greatly in the same person at different ages and with different health conditions.

In most cases, all test indications and criteria cannot have exact reference values. Generally accepted norms fluctuate within a set range. The data obtained is already compared with them: the biochemical analysis showed the norm, or, conversely, whether changes can occur. Any hospital or medical center uses different devices and methods to determine tests, so each individual medical institution sets its own standards for each indicator.

Biochemical analysis carried out approximately simultaneously in different structures may differ. Each clinic that conducts biochemical analysis sets its own requirements and criteria. Therefore, the same analysis indicator, its decoding, is interpreted differently.

First of all, you need to familiarize yourself with the procedure itself (blood test), the method of its implementation and the reason for the appointment. You need to prepare for the tests. It is prohibited to eat or drink anything. It is necessary to take a blood test on an empty stomach, which will further increase the level of accuracy of the results.

Most often, it takes no more than one day to check all blood components. However, the operation can be speeded up. A blood test using this method involves the study of such important blood components as proteins, enzymes, pigments, vitamins, carbohydrates, nitrogenous substances and inorganic elements.

In blood serum, lactate dehydrogenase exists in five isoenzyme varieties - LDH-1, LDH-2, LDH-3, LDH-4, LDH-5. These are special molecular forms of lactate dehydrogenase, which have their own functional specificity. Biochemists depict LDH as a tetramer consisting of a certain number of subunits of two types - M (from the English word “muscle”) and H (from the English word “heart”). Thus, the place of localization of one or another type of LDH is implied - in ordinary muscles and the heart.

Attention! In the practice of biochemical blood analysis, the parameter most often used is total LDH, that is, the generalized, total content of all LDH isofractions.

LDH norms in the LHC

The normal level of LDH in the blood of people of different ages is as follows:

• in a newborn – up to 2000 U/l
• in a child under 2 years old – 425 U/l
• in a child from 2 to 12 years old – 295-300 U/l
• in a child over 12 years old – 250 U/l
• in adults – 235-250 U/l

In cases where one or another LDH isoenzyme is needed as a biochemical marker, they resort to special laboratory tests - the Sevel-Tovarek method, the thermal inhibition method, and the urea inactivation method. The listed tests allow you to measure the level of activity of isoenzymes under different conditions and identify the presence of possible pathology. The table below provides a list of the normal level of isoenzyme activity in each of the listed types of research.

When cells in the human body die, they break down into various biochemical compounds. Almost all of these newly formed substances are toxic or have no utilitarian value for the body, so it removes them beyond its limits with the help of blood (the body’s waste products are delivered to the liver and kidneys).

Lactate dehydrogenase is one such organic compound. It is found in certain tissues of the body, so the presence of it in excess of the norm in the human blood will indicate excessive cell death in a certain part of it. In the case of LDH isofractions, the localization of the phenomenon can be clearly indicated, since each of the isoenzymes has its own specific location:

• Lactate dehydrogenase-1 is found in greatest quantities in the tissues of the myocardium and brain (brain and bone). It is also found in kidney tissues and in the biochemical composition of platelets and red blood cells.
• Lactate dehydrogenase-2 exceeds the level of LDH-1 in erythrocytes and platelets.
• Lactate dehydrogenase-3 is found in the tissues of the spleen and lungs, as well as many glands of the human endocrine system - thyroid, parathyroid, adrenal glands, pancreas.
• Lactate dehydrogenase-4 is a constant companion of LDH-3. It is found in all tissues where this isoenzyme is present, but in smaller quantities. It is also included in the biochemical composition of sperm, granulocytes, and hepatocytes.
• Lactate dehydrogenase-5 exceeds the level of other LDH isoenzymes in the liver and skeletal muscle. The latter also contains less LDH-4 and LDH-3. LDH-5 is found in small amounts in male germ cells.

Attention! An excess of one or another isoenzyme in the blood will be evidence of the development of pathology in this organ.

At the beginning of the article, we already noted that the LDH indicator is used not only to identify pathologies, it is also needed to monitor the patient’s health status. Lactate dehydrogenase is convenient as a clinical marker of the patient’s general health in that it can easily track the dynamics of a person’s recovery.

The most characteristic ailments that are accompanied by an increase in LDH in the blood are the following diseases and pathological phenomena:

• Injuries. An ordinary bruise left after a strong blow is damage to the skeletal muscles, and, therefore, a reason for an increase in the level of LDH in the blood. Other injuries can also cause an increase in the level of this enzyme if they affect organs in which it is present - the heart, liver, brain.
• Lesions of the endocrine glands (pancreas, adrenal glands, thyroid) of various etiologies will increase the LDH content in the blood. Therefore, the enzyme is an excellent marker for monitoring diseases such as pancreatitis, hyperthyroidism, hypothyroidism, Hashimoto's thyroiditis, Addison's disease, cancer.
• Blood diseases. Considering that lactate dehydrogenase is a component of many blood cells, it is not surprising that it is used as a marker for monitoring various blood diseases, primarily leukemia and hematosarcomas.
• Anemia of various types. In anemia, the death rate of blood cells and skeletal muscle cells is higher than normal.
• Liver diseases. Hepatitis of various etiologies causes the death of hepatocytes - liver cells, the biochemical composition of which includes LDH.

Attention! Cirrhosis and liver carcinoma in the advanced stage change the liver tissue so much that it begins to lack LDH, therefore physiological biochemistry does not use this enzyme to monitor the development of these pathologies.

Here everything is much stricter with preparation, preparation for the blood test for LDH. You should not eat anything for twelve hours before the test. Experts also do not advise smoking and drinking drinks containing alcohol, actively engaging in physical exercise and eating a lot. Also, don’t spoil your mood.

Before the examination, the patient needs to calm down and sit in the corridor in front of the office to bring his pulse to normal and calm his heart.

You should also consider the following:

• Stop taking ascorbic acid, anti-seizure medications, and certain medications four days before the test.
• There is no need to take hemodialysis before the procedure.

Doctors warn that a heart valve and possible hematological abnormalities are affecting blood tests.

LDH analysis is a non-specific study. Before cardiologists recognized the troponin test as more effective, blood tests for lactate dehydrogenase levels were prescribed to diagnose heart problems.

Why is it necessary to undergo examination?

A biochemical blood test for lactate (LDH) may be prescribed if the presence of a particular disease is suspected. At the moment, according to historical data in medicine, several main ones can be distinguished:

• these are diseases of the hepatobiliary system;
• after myocardial infarction – carried out in early diagnosis, differential and as monitoring);
• when diagnosing tumors;
• to determine the type of anemia - increased LDH;
• other accompanying diseases.

Preparing for the study

LDH is carried out when there is a suspicion that organs or their systems have been injured. It is tissue damage that provokes an increase in the level of this enzyme in the blood. This is especially true for the tissues of the heart, brain, lungs, kidneys, and skeletal muscles.

If melanoma is suspected, blood LDH is also performed. What does it mean? The fact is that this analysis allows you to identify metastases in organs and lymph nodes. This research method for melanoma cannot be called specific, but it allows you to monitor the patient’s condition in the postoperative period, as well as determine the stage of tumor development. In addition, in the case of effective therapy, the level of the enzyme in the blood decreases, so this marker is used to determine the dynamics of treatment.

A biochemical blood test for lactate is carried out using a special method, which in medicine is written as a UV test (DGKC). As a rule, an analysis of this type should be recorded in the patient's referral. This is not only a special technique and transcript at the end, but also a short medical description.

Most often, in modern and high-quality laboratories, results are given out on the second day, so you won’t have to wait long. It is also worth remembering the quality of the results, because false results are strictly not allowed, especially when LDH is elevated. This may seriously affect the patient's future treatment. LDH differences are observed only in children and adults. The gender of the person is not important in this case.

For example, in adults the norm should be in the range from 240 to 480 IU/l. As for children, their differences go up to their years. In children on the first day of life – more than 1327 IU/l; 2-5 days – (amp)lt; 1732 IU/l; 6 days-6 months – (amp)lt; 975 IU/l; 7-12 months – (amp)lt; 1100 IU/l; 1 -3 years – (amp)lt; 850 IU/l;

If the indicator is significantly increased, then it is necessary to pay attention directly to those possible reasons that could cause the increase. A biochemical blood test for lactate is carried out in the same way for adults and children, so it cannot be said that this is a pleasant procedure and it will not hurt for children.

After blood sampling, only serum is extracted for testing, and only from it is it determined whether the patient’s lactate is high or low. There are cases when a biochemical blood test is not ready on the second day after donation
. This is because under the right storage and transportation conditions, blood can be stored for a certain period of time.

The lactate test may be elevated or decreased, and may also be within acceptable limits. If LDH is elevated, this indicates the presence of pernicious or megaloblastic anemia, intense carcinomatosis or hepatitis. Lactate may also be elevated during hypoxia, various shocks, or hyperthermia. The analysis in this case will be negative, since the main indicator is increased and goes beyond the permissible norm.

Increased activity of lactate dehydrogenase under physiological conditions is observed in pregnant women, newborns, and in persons after intense physical exertion.

Violation of the storage conditions of biomaterial in the laboratory, the patient taking hormonal medications, physical activity and non-compliance with the rules of preparation for the study are a possible reason for elevated LDH levels in a biochemical blood test. If there is any doubt about the accuracy of the results, the doctor will prescribe a repeat test.

Dangers and Consequences

A significant increase in the LGD indicator indicates the presence of a pathological process in the human body
. Lack of treatment or late diagnosis of the disease can lead to unpleasant consequences for the patient. Existing diseases can become severe and chronic, increasing the risk of strokes, heart attacks, and liver pathologies.

The LDH (lactate dehydrogenase) test is a nonspecific test that is used when a number of diseases and conditions are suspected. The enzyme enters the blood plasma during the destruction of almost any cell in the body, including bacterial ones. Therefore, the level of LDH in the blood is a general indicator of tissue and cellular damage. Sometimes the concentration of a substance is assessed using cerebrospinal or pulmonary fluid in the presence of certain diseases.

The importance of the enzyme in the body

Interest in what LDH is in a biochemical blood test is associated primarily with myocardial infarction. Previously, this test was used to diagnose and monitor damage to cardiac tissue, but now the troponin test is considered more accurate and informative. Lactate dehydrogenase (LDH) is not a specific indicator of cardiac cell damage and is no longer used in patients with suspected acute coronary syndrome. Typically, the transcript of a biochemical blood test contains this indicator. Lactate dehydrogenase in the blood is an important enzyme involved in the reactions:

Glucose oxidation;

Lactic acid production.

The peculiarity of the enzyme is that it does not accumulate in cells, but is completely broken down and excreted. LDH is essential for converting glucose into energy for the functioning of all cells in the body. The reaction is mediated by oxygen, which helps break down glucose into water, carbon dioxide and energy. Without oxygen, energy production decreases by 20 times and lactic acid accumulates. The enzyme LDH is necessary for its oxidation and return to glucose metabolism. Unlike healthy cells, cancerous tumors feed without oxygen.

When is the test prescribed?

The test is used when acute and chronic tissue damage is suspected, as well as to evaluate progressive diseases. In rare cases, the test can help identify target organ damage.

The enzyme is determined in a venous blood sample. After injury, LDH is elevated, rises for 48 hours and reaches a maximum after 2-3 days, then gradually decreases. The normal level is restored within 10 days.

Research shows that the LDH blood chemistry test is an indicator of cancer development and progression. Even after taking into account the factor of age and stage of the disease in patients, a strong association with the risk of death remained. This relationship was true for all types of malignant tumors.

The blood LDH test can be used to detect and evaluate:

Acute or chronic tissue damage;

Progression of anemia and severe infection;

Course of oncological diseases after chemotherapy for lymphoma, leukemia, melanoma, neuroblastoma. High values ​​indicate poor prognosis for patient survival.

The doctor prescribes determination of LDH levels in other body fluids:

To distinguish between bacterial and viral meningitis by analyzing cerebrospinal fluid.

To identify the cause of the accumulation of fluid in the chest or abdomen (pleural, peritoneal and pericardial fluids) due to trauma and inflammation or due to an imbalance of pressure within the blood vessels and the amount of protein in the blood.

A blood test for LDH (biochemistry) is taken on an empty stomach from a vein.

The last meal 8 hours before the examination should not contain too much fatty or protein foods.

Be sure to inform if you need to take medications regularly. Aspirin, hormonal contraceptives and antidepressants affect clotting and may show elevated values.

Intense training the day before can lead to an increase in the enzyme, as it increases energy expenditure and the need for the breakdown of glucose.

Many factors influence the results of the analysis, and they are not always a cause for concern and further examination:

Hemolysis of blood samples leads to false-positive results. Violation of the rules for storing samples and rough processing affect the accuracy.

With increased platelet count, serum LDH level also increases and does not show the real picture.

During hospitalization with suspected myocardial infarction and acute pancreatitis, LDH analysis is performed without taking into account the recommendations. Often, the LDH indicator is used to assess the dynamics of the disease and the patient’s recovery.

Norm of LDH in the body and interpretation of the analysis

When testing blood, the norm is usually indicated in units/l, which means one per liter. The interpretation of the analysis takes into account the age and gender of the patient. A relatively small amount of the enzyme is found in the blood of a healthy adult. In a child under two years of age, the norm is considered to be within 430 units/l.

An increase in lactate dehydrogenase occurs during pregnancy, in newborns, and in professional athletes.

Based on the identified marker, it is impossible to determine which cells were damaged. Therefore, when deciphering LDH, it is necessary to know what its isoenzymes are. Some laboratories conduct additional tests that determine several forms of the substance, starting with the most mobile:

The first indicates a problem with the heart, kidneys and red blood cells;

The second is found mainly in cardiomyocytes and erythrocytes;

The third is found in lung tissue, endocrine glands and adrenal glands;

the fourth is an enzyme in white blood cells, liver, placenta and male testicles and muscle tissue;

The fifth is found in all organs containing LDH-4, as well as skeletal muscles.

Deciphering biochemistry for increased LDH in the blood is now considered less informative.

High values ​​of all isoenzymes determine the pathology of several organs. Myocardial infarction with congestive heart failure causes lung damage and liver congestion. In cancer and autoimmune diseases such as lupus, lactate dehydrogenase is generally elevated. Hypoxia, shock and burns are accompanied by cell death, which shows an increase in LDH. Caffeine also affects the amount of enzyme in the blood.

The dynamics of the first isoenzyme are more sensitive and specific than the increase in LDH in general. Usually the level of the second isoenzyme is higher than the first. If the concentration of LDH-1 increases relative to LDH-2, a heart attack is diagnosed. Typically, the LDH level in the blood is exceeded 12-24 hours after damage to heart tissue and for two days in 80% of cases. A normal LDH-1/LDH-2 ratio is reliable evidence that there was no attack. The ratio of total LDH to LDH-1 is called hydroxybutyrate dehydrogenase. Therefore, during a heart attack:

the LDH/GBDG figure is reduced (less than 1.30);

the LDH-1/LDG-2 ratio approaches 1 and sometimes exceeds this value.

On the first day, myocardial infarction is diagnosed by the creatine kinase indicator, and a day later - by the enzymatic study of LDH. The activity of the substance is directly related to the area of ​​damage to the heart muscle.

Other serious diseases are reflected in the ratio of isoenzymes and coefficients:

Hemolytic anemia is characterized by a low LDH/GBDG figure - up to 1.3 and below;

In megaloblastic anemia, LDH-1 significantly exceeds LDH-2;

the general level increases during acute necrotic processes and cell death, such as damage to the kidney parenchyma;

tumors in the gonads (ovaries and testes) are accompanied by an isolated increase in LDH-1.

Most often, LDH is elevated due to the destruction of tissue of the liver and kidney parenchyma, and the death of platelets and red blood cells.

LDH in a blood test is considered in relation to other indicators:

With anemia, red blood cells are destroyed, which releases large amounts of LDH into the blood. The disease is diagnosed against the background of low hemoglobin. Weakness, pallor, shortness of breath may be indications for examination.

Blood cancer is associated with the production of abnormal blood cells, which is reflected in the levels of many indicators: LDH, aspartate aminotransferase, bilirubin, urea. At the same time, there is a decrease in the level of glucose and the blood clotting factor fibrinogen. A biochemical blood test allows one to suspect pathology and refer the patient to identify tumor markers.

Along with the LDH level in the blood, which indicates the death of pancreatic cells, bilirubin and glucose will increase. The primary indicator is the level of the pancreatic enzyme amylase.

Reasons for the increase

Elevated LDH levels can be caused by various diseases:

• stroke;
• some types of anemia (pernicious and hemolytic)
• kidney and liver diseases;
• muscular dystrophy;
• pancreatitis;
• infectious mononucleosis;
• some forms of cancer.

The concentration of the enzyme increases after the administration of anesthetics and aspirin, as well as after intense physical exercise. Normal and decreased LDH levels are not pathological. A factor that reduces the indicator is the consumption of a large dose of ascorbic acid (vitamin C).

The reasons that lactate dehydrogenase is elevated are varied: HIV infection, sepsis, acute kidney disease, infarction of the intestines and lungs, bone fractures, rash on the body.

LDH is low when transudate accumulates in body cavities, such as the abdomen, usually caused by congestive heart failure or cirrhosis.

LDH in the blood - what is it, reasons for the increase in a biochemical blood test

Lactate dehydrogenase (LDH) in the blood is a laboratory test with low specificity. However, its deviation from the norm is a sufficient condition for conducting a comprehensive examination of the patient. It is necessary for the primary diagnosis of pathologies in the heart, lungs, kidneys, various oncological pathologies and destruction of muscle tissue in humans.

What is LDH in the blood?

In order to understand the purpose of the test, you should first understand what LDH is in a biochemical blood test?

Lactate dehydrogenase (LDH) in the blood is an enzyme localized inside cells. The composition necessarily includes zinc ions. The main function is to catalyze the oxidation of lactic acid to pyruvate. Almost all cells in the human body contain the enzyme LDH. The maximum concentration is observed in skeletal (9000 units/g) and cardiac (25,000 units/g) muscles, as well as in the kidneys (15,000 units/g), lungs (9500 units/g) and liver (9000 units/g).

In case of cell damage, the enzyme is actively released into the bloodstream. Blood cells also contain LDH, however, their content is insignificant. That is why, even with slight destruction of the tissues of any organ, there is a sharp increase in the level of LDH in the blood serum, which is used to diagnose various diseases. This fact allows us to classify the blood test for LDH as a highly sensitive, but low-specific criterion.

Enzyme isoforms

From the point of view of the information content of the results obtained, LDH isoforms are more preferable due to an increase in the level of specificity. There are 5 known isoforms of the enzyme with characteristic physicochemical properties.

Isoform

The organ that produces

Indications for the study

A doctor can write out a referral for a biochemical analysis of blood serum to determine the level of LDH if:

• the patient experiences symptoms of chronic or acute damage to the integrity of cells and tissues;
• a person feels severe pain in the chest area, the cause of which may be myocardial infarction or angina pectoris;
• it is necessary to control the course of chronic pathologies, including oncology;
• large-scale screening of human health is carried out.

Norm of LDH in the blood

Any interpretation of the results should be carried out exclusively by a specialist. Due to the low specificity of the criterion under consideration, its isolated use for the final diagnosis of the disease is prohibited. Indicators of normal LDH concentrations in adults and children in the blood are shown in the table.

Normal values, U/l

It should be noted that normal LDH levels are higher in men than in women. Deviation from the reference (normal) values ​​to a greater or lesser extent indicates the development of a pathological process.

The value of LDH isoenzyme indicators

The activity of isoenzymes is determined by the degree of inactivation by urea. It has been established that the level of inhibition of the enzymatic activity of human serum by urea ranges from 26 to 36%. This indicator is considered as a standard value for comparing the inhibitory properties of the five isoenzyme fractions.

Isoenzyme

Inactivation level of total urea activity, %

The table shows that each fraction has its own level of inhibition. Based on the known data on the priority organ of synthesis of each isoenzyme, and the obtained test results, it is possible with a high degree of probability to determine the organ in which the disease develops.

Decoding the results: reasons for the decrease

It is noted that LDH levels are reduced in the following cases:

• the patient has oxalates (salts and esters of oxalic acid) and urea, which weaken the enzymatic activity of LDH;
• taking medications that reduce enzyme activity (antibiotics, ascorbic acid);
• the effectiveness of the chosen treatment tactics, leading to normalization of the value of the criterion under consideration.

Reasons for increased LDH in a biochemical blood test

The criterion under consideration may deviate from normal values ​​in a number of different diseases. The reasons for the increase in lactate dehydrogenase concentration may be:

• myocardial infarction, accompanied by ischemic necrosis of the middle layer of cardiac muscle tissue;
• blockage of a pulmonary artery with a blood clot or pulmonary infarction;
• blood pathologies, which are characterized by the destruction of red blood cells (various types of anemia, hemolysis, severe intoxication);
• malignant tumors affecting various organs and tissues, often accompanied by metastasis;
• disturbances in liver function due to chronic and acute hepatitis, Gospel disease or alcohol intoxication;
• kidney pathologies (glomerular nephritis, pyelonephritis);
• muscle tissue atrophy or injury;
• open and closed fractures;
• congestive heart or coronary failure;
• inflammation of heart muscle tissue;
• mononucleosis, viral etiology;
• acute attack of pancreatitis;
• seizures;
• alcoholic delirium (mental abnormalities due to sudden withdrawal of alcohol);
• burn disease;
• premature placental abruption;
• hyperfunction of the thyroid gland.

When identifying the causes of increased LDH in women and men, it is necessary to exclude the influence of factors that can lead to unreliable results:

• improper blood sampling, resulting in the destruction of red blood cells in the test tube (hemolysis);
• neglect of the rules of preparation for the delivery of biomaterial: physical and emotional stress, smoking, alcohol, poor diet;
• the use of treatment methods accompanied by electrical stimulation of the patient a week before the analysis;
• excess platelets in the blood;
• taking medications that activate the enzyme system.

Normalization of LDH levels in the blood

Patients often wonder how to reduce enzyme levels? To do this, it is necessary to initially establish the exact cause of the increase in LDH. Only by eliminating the disease that was the cause is it possible to return the indicator to normal values. Therapy for each pathology has its own characteristics:

• after the first signs of myocardial infarction, a person needs to provide first aid. Any delay in treatment can lead to death and serious complications. In order to assess the risk of relapse, a control measurement of LDH levels is carried out, which should return to normal with adequate therapy;
• in case of anemia caused by iron deficiency, the patient’s diet is corrected and iron-containing drugs are prescribed. A favorable outcome is considered to be an increase in hemoglobin levels and a decrease in LDH;
• in oncopathology, large-scale screening of the patient is necessary to assess the size of the tumor, the presence of metastases and the degree of organ damage. In this case, assessment of the effectiveness of treatment includes analysis of LDH and main tumor markers. The absence of positive dynamics, expressed in a decrease in the criteria under consideration, is a reason to transfer the patient to more aggressive methods of treatment;
• in case of acute pancreatitis, it is necessary to place the patient in a 24-hour hospital. Treatment includes drips with painkillers, antibacterial and anti-inflammatory drugs. As the patient's condition improves, all biochemical parameters return to normal.

How is LDH analysis performed?

To assess the level of LDH and its enzymatic activity, 2 groups of methods are used:

• spectrophotometric, the essence of which is to determine the difference in the absorption spectra of the oxidized form of NAD (a coenzyme of all living cells) from the reduced one;
• colorimetric, subdivided into dinitrophenylhydrazine - determination of pyruvate concentration, and redoxindicator - identification of certain molecules using indicators that change color.

An optical test is used as standards for determining the enzymatic activity of LDH, and electrophoresis is used for isoenzymes. When issuing analysis results, the laboratory must indicate the chosen method.

How to prepare for research

Preparation for the test is necessary to obtain the most reliable and accurate results. The biological material is venous blood collected from the cubital vein on the elbow. Recommendations before analysis:

• blood is donated strictly on an empty stomach; fatty and fried foods must be excluded from the diet for 1 day;
• It is strictly forbidden to drink juice, tea and coffee 12 hours before collecting biomaterial; clean water without gas is allowed;
• do not smoke for 30 minutes;
• Avoid drinking alcohol and taking medications for at least 48 hours. If it is impossible to discontinue any medications, notify the laboratory employee about their use;
• limit physical and emotional stress in 1 hour.

To summarize, it is necessary to emphasize:

• LDH in a biochemical blood test is a low-specific criterion that allows one to predict a number of diseases. To clarify the diagnosis, additional laboratory and instrumental examinations are required;
• when deciphering the results, it is important to take into account that the reference value is different for a child and an adult;
• in case of necrosis and infarction, which are characterized by cell destruction, it is recommended to repeat the analysis after the acute stage. This is necessary to assess the degree of tissue destruction and the severity of pathology;
• identifying the degree of activity of enzyme isoforms allows us to clarify the location of the pathology.

Yulia Martynovich (Peshkova)

Certified specialist, in 2014 she graduated with honors from the Orenburg State University with a degree in microbiologist. Graduate of the graduate school of the Orenburg State Agrarian University.

In 2015 At the Institute of Cellular and Intracellular Symbiosis of the Ural Branch of the Russian Academy of Sciences, she completed advanced training in the additional professional program “Bacteriology”.

Laureate of the All-Russian competition for the best scientific work in the category “Biological Sciences” 2017.

LDH is elevated in a child Komarovsky

Hello. The child is 2’5 years old. Height 102, weight 17.7 kg. I don’t know where to write anymore, I’ve read similar topics here. Maybe moms with a similar problem can respond.

At 4 months the problem was discovered. The child was hospitalized with suspected pneumonia. They took a picture, everything was fine, but they started injecting Ceftriaxone to be on the safe side, and then on the second day it turns out that in biochemistry, asat and alate were increased by about three times, and asat and alate were twice as high. This is what I remember. Ceftriaxone was abruptly discontinued, the child was on a rehydron drip, in my opinion. For three days they dug around and kicked us out, without even figuring out what was what. Ceftriaxone was thought to have caused hepatoxicity. But something about this alarmed me. Every year we retake CPK tests twice as high as normal, ASAT is higher than normal, and ALT is normal. Lots of questions for doctors, no answers. We passed all the hepatitis and infections that the gastroenterologist prescribed... all negative. I was wary about myopathy, but thank God it wasn’t it. At the age of 2, I decided to act independently in search of an answer, but I also looked closely at the child’s behavior and development. I hoped it would grow out of it, but I didn’t get too depressed. Biochemistry at two years old showed asat within the highest normal range, alt normal, cfk normal, ldg 680. As for ldg... the question of the liver immediately arose, but I wanted to see cfc-mv. And at 2.5 degrees it was time to take him to where they do this analysis, he turned out to be elevated. 40 when the norm is up to 20. As if before pregnancy, I had a good experience with this isoenzyme and with tonsilogenic myocardial dystrophy I had periodically increased CPK-MB. The myocardial cells were destroyed, fortunately my condition was reversible, I removed the tonsils. Shortness of breath, pain in the heart and cfc are common, that the heart rate returned to normal after the operation, as did my terrible condition. What now we have KFK MV 40, LDG550. I must say that my grandmother with coronary heart disease has the same biochemistry as my child. I can imagine what the baby is experiencing. Asat is in the upper limit, which is also suggestive. The general kfk has become normal, perhaps he also jumps occasionally, they just didn’t catch it. Ultrasound of the abdominal cavity dated July 18, 2018 shows hepatomegaly, i.e. The enlargement of the liver, as the ultrasound specialist said, is a little higher than normal - supposedly it’s not scary, mommy. But then tell me where to send the tests. I understand that you need to take troponins I, T, C to understand whether cardiomycytes are being destroyed and to do an ultrasound of the heart. By the way, the ultrasound in the maternity hospital was normal, without pathologies. It is not so easy to get a heart ultrasound in our muhosransk, nor is it so easy to find a good doctor. But I think we’ll do an ultrasound at the beginning of September, but troponins, even in Minsk, our capital, they don’t do them, it’s only in Moscow, I’m not sure that we’ll get there together. I study a lot of information and understand that we can talk about xp. Heart failure, heart defect, congenital or acquired after some kind of virus, of which we had quite a few during this time. But... the liver is also in question... this is an ultrasound where the liver is larger than normal, then low hemoglobin from birth, a reaction to fatty foods in the form of the smell of acetone and ketone bodies in the urine. We put him on a diet, nothing fatty, a minimum of chocolate, and we feed him cereal. Reaction to Maltofer, prescribed at 4 months, I fell for our stupid pediatrician and gave it. On the second day, the child screamed so loudly that the grandmother was taken away with a heart attack. Maltofer was canceled, and the next day they ended up in the infectious disease department, the child was lethargic, apathetic, they suspected pneumonia, they also gave Ceftriaxone after that, but then the tests came up. You could blame it on infection, you could blame it on drug poisoning, you could blame it on being vaccinated against hepatitis in the maternity hospital, or you could blame it on the fact that I was breastfeeding during my period, and at the same time I was injected with Ceftriaxone for endometritis in the hospital. I don’t know what caused such problems; the correct diagnosis and treatment are important to me in order to improve or prevent the prognosis. And the prognosis, as I understand it, may be disappointing (((I’ll say about the child: he always ate well, developed and gained weight normally. He often burped during breastfeeding, but not like a fountain. Gerb was ruled out. Low hemoglobin from two months. Wait 120. Glycated glucose hemoglobin is normal. Thyroid hormones are normal. Complete biochemistry a month ago.

• hepatitis;
• jaundice;
• liver pathologies (cirrhosis);
• blood diseases;
• leukemia;
• wasting of muscle fibers;
• kidney diseases;
• acute pancreatitis;
• some medications;
• burns.

Norm LDH in children

• from 1 to 4 days of life - But important rules should not be missed:

1. Blood is taken early in the morning, on an empty stomach.
2. In terms of nutrition, you can leave everything as it is.
3. You can do sports exercises at the same rhythm, but without overworking yourself.

Otherwise, there are no special instructions. Despite the fact that the procedure is painless, it is still something unknown and unusual for children. So, before the upcoming procedure, it’s worth preparing him: talk to him calmly, tell him everything as it will happen. When the child is ready, then the procedure will seem normal.

The analysis for lactate dehydrogenase may exceed normal standards, be reduced, or be equal to normal. When LDH is elevated, we can talk about the presence of certain types of anemia, hepatitis, hypoxia, or carcinomatosis.

Also, the child has not yet had time to get used to all manifestations of the external environment. The body is just adapting to all kinds of changes. This is how many doctors explain the frequent illnesses of the younger generation. Over time, the immune system, knowing this or that irritant, is able to give its response, then infection will not occur. But preventive measures should not be forgotten; they will help increase immune defense.

Thank you for your answer, indeed, the rest of the indicators are normal (that’s why I didn’t write them), I quoted the norms from the form, as I understand they are indicated for this laboratory (done in the clinic)

I understand that this is not a medical forum, but it’s a long wait to see a doctor by appointment.
I hope that not only mothers, but also doctors come here
Maybe there’s something else to examine for now, so as not to waste time

Among the diseases in the past, I was diagnosed with venous pancreatitis, an ultrasound in December was normal, and in April it was dyspancreatism.

Why is LDH elevated in a child, what are the consequences?

If LDH is elevated in a child, doctors become wary. It is necessary to respond to any changes in the body, especially in childhood. This enzyme is present in almost all human organs. The smaller the child, the higher this figure will be. It should decrease with age. Lactate dehydrogenase can increase in women during pregnancy, infants, and athletes.

Causes and consequences of increased LDH

The reasons why lactate dehydrogenase is elevated are varied.

LDH concentrations can be affected by various diseases. In most cases, the diagnosis is muscle wasting, pulmonary infarction or anemia.

Diseases in which LDH increases include:

• hepatitis;
• jaundice;
• liver pathologies (cirrhosis);
• blood diseases;
• leukemia;
• wasting of muscle fibers;
• kidney diseases;
• acute pancreatitis;
• some medications;
• burns.

An analysis to determine the level of LDH is carried out:

• To determine how affected the patient's tissues are.
• To find out the cause of pain in the chest area.

• In order to find the cause of the destruction of red blood cells.
• To monitor the course of cancer.
• To conduct an examination of the liver and kidneys.
• After receiving serious muscle injuries.

The resulting material for research is stored for no more than 48 hours, the temperature should be from 18 to 25 o C. If the sample is placed in the cold or frozen, the concentration of LDH will begin to rapidly decrease, the result will be false.

Norm LDH in children

Let's look at the standard indicators of LDH levels in childhood:

LDH is elevated in a child