About all

Normal range of aspartate aminotransferase. Understanding Aspartate Aminotransferase (AST) Test: Reference Ranges, Interpretation, and Implications

What is the normal range for AST levels in blood. How does AST testing help diagnose liver damage. When should you get an AST test. What factors can affect AST test results. How is the AST test performed and interpreted.

Содержание

What is Aspartate Aminotransferase (AST) and Why is it Important?

Aspartate Aminotransferase (AST), also known as Serum Glutamic-Oxaloacetic Transaminase (SGOT), is an enzyme primarily found in the liver. However, it’s also present in smaller quantities in other organs such as the heart, kidneys, brain, and muscles. The AST test is a crucial diagnostic tool used to assess liver health and function.

AST plays a vital role in amino acid metabolism and is normally contained within liver cells. When liver cells are damaged or die, AST is released into the bloodstream, causing blood levels to rise. This makes the AST test an essential indicator of liver damage or disease.

The Multifaceted Role of the Liver

The liver is a remarkable organ with numerous essential functions:

  • Bile production to aid in digestion
  • Removal of toxins and waste products from the blood
  • Synthesis of proteins and blood clotting factors
  • Regulation of blood sugar levels
  • Storage of vitamins and minerals

Given its critical role in maintaining overall health, monitoring liver function through tests like AST is crucial for early detection and management of liver disorders.

Normal AST Levels and Reference Ranges

AST levels are typically measured in units per liter (U/L) of blood. The normal reference ranges for AST can vary slightly depending on the laboratory and testing method used. However, generally accepted ranges are:

  • Males: 10 to 40 U/L
  • Females: 9 to 32 U/L

It’s important to note that these ranges may differ based on age, gender, and individual laboratory standards. Always consult with your healthcare provider for interpretation of your specific results.

Factors Influencing AST Levels

Several factors can affect AST levels, potentially leading to elevated results even in the absence of liver disease:

  • Intense physical exercise
  • Certain medications
  • Muscle injuries or disorders
  • Heart conditions
  • Pregnancy
  • Obesity
  • Alcohol consumption

Understanding these influencing factors is crucial for accurate interpretation of AST test results and avoiding false positives.

When Should You Get an AST Test?

An AST test may be recommended by your healthcare provider in various scenarios:

  1. Routine health screenings
  2. Monitoring known liver conditions
  3. Evaluating the effectiveness of liver disease treatments
  4. Investigating symptoms suggestive of liver problems

Symptoms that might prompt an AST test include:

  • Jaundice (yellowing of skin or eyes)
  • Fatigue and weakness
  • Abdominal pain or swelling
  • Loss of appetite
  • Dark urine or pale stools
  • Unexplained weight loss
  • Itchy skin

Additionally, individuals with risk factors for liver disease, such as heavy alcohol use, obesity, diabetes, or a family history of liver disorders, may benefit from regular AST testing as part of their health monitoring.

The AST Test Procedure: What to Expect

The AST test is a simple blood test that requires minimal preparation. Here’s what you can expect during the procedure:

  1. A healthcare professional will clean an area on your arm with an antiseptic.
  2. An elastic band may be tied around your upper arm to make the vein more visible and easier to access.
  3. A small needle will be inserted into a vein to draw a blood sample.
  4. The blood will be collected in a vial or tube.
  5. The needle will be removed, and pressure applied to stop any bleeding.
  6. A bandage will be placed over the puncture site.

The entire process typically takes only a few minutes. While generally safe, minor risks may include slight pain, bruising, or rarely, infection at the needle insertion site.

Preparing for the AST Test

In most cases, no special preparation is needed for an AST test. However, it’s important to inform your healthcare provider about any medications or supplements you’re taking, as some can affect the test results. Your doctor may advise you to avoid certain medications or activities before the test to ensure accurate results.

Interpreting AST Test Results: What Do They Mean?

Interpreting AST test results requires considering various factors and often involves comparing AST levels with other liver enzyme tests, particularly Alanine Aminotransferase (ALT). Here’s a general guide to understanding AST results:

Normal AST Levels

If your AST levels fall within the normal range (typically 10-40 U/L for males and 9-32 U/L for females), it generally indicates that your liver is functioning properly. However, normal AST levels don’t completely rule out all liver conditions, especially if other liver function tests show abnormalities.

Mildly Elevated AST Levels

Slightly elevated AST levels (1-3 times the upper limit of normal) may indicate:

  • Mild liver inflammation
  • Early stages of liver disease
  • Non-alcoholic fatty liver disease (NAFLD)
  • Recent intense physical exercise
  • Certain medications

Moderately Elevated AST Levels

AST levels 3-20 times the upper limit of normal may suggest:

  • Chronic hepatitis
  • Alcoholic liver disease
  • Drug-induced liver injury
  • Cirrhosis
  • Muscular disorders

Severely Elevated AST Levels

AST levels more than 20 times the upper limit of normal often indicate severe liver damage, which may be caused by:

  • Acute viral hepatitis
  • Severe drug or toxin-induced liver injury
  • Ischemic hepatitis (reduced blood flow to the liver)
  • Acute liver failure

It’s crucial to remember that AST levels alone don’t provide a complete picture of liver health. Your healthcare provider will interpret your results in conjunction with other liver function tests, your medical history, and any symptoms you’re experiencing.

AST/ALT Ratio: A Key Diagnostic Tool

The ratio of AST to ALT levels can provide valuable insights into the nature and severity of liver damage. This ratio is particularly useful in differentiating between various liver conditions:

  • AST/ALT ratio < 1: Typically seen in viral hepatitis and non-alcoholic fatty liver disease
  • AST/ALT ratio > 2: Often indicative of alcoholic liver disease
  • AST/ALT ratio > 1 but < 2: May suggest cirrhosis or severe liver damage from various causes

The AST/ALT ratio, combined with other clinical and laboratory findings, helps healthcare providers make more accurate diagnoses and tailor treatment plans accordingly.

Beyond Liver Disease: Other Conditions Affecting AST Levels

While AST is primarily associated with liver health, elevated levels can also indicate issues in other organs or systems:

Cardiac Conditions

AST levels can rise following a heart attack or in cases of congestive heart failure. This is because AST is also present in heart muscle cells, which release the enzyme when damaged.

Muscular Disorders

Conditions affecting skeletal muscles, such as muscular dystrophy or rhabdomyolysis, can lead to increased AST levels. Intense exercise or muscle injuries may also cause temporary elevations.

Hemolytic Anemia

This condition, characterized by the premature destruction of red blood cells, can result in elevated AST levels due to the release of the enzyme from damaged cells.

Pancreatitis

Inflammation of the pancreas can sometimes cause a rise in AST levels, although this is typically accompanied by more specific pancreatic enzyme elevations.

These non-hepatic causes of elevated AST levels underscore the importance of comprehensive evaluation and the consideration of a patient’s full clinical picture when interpreting AST test results.

Complementary Tests: Building a Complete Liver Health Profile

While the AST test provides valuable information about liver health, it’s often performed as part of a broader panel of liver function tests. These additional tests help create a more comprehensive picture of liver health and function:

Alanine Aminotransferase (ALT)

ALT is another enzyme found primarily in the liver. It’s often more specific to liver damage than AST and is usually tested alongside AST. The AST/ALT ratio, as discussed earlier, can provide insights into the nature of liver damage.

Alkaline Phosphatase (ALP)

ALP is an enzyme found in various tissues, including the liver, bones, and bile ducts. Elevated levels can indicate liver disease, particularly those affecting bile flow, such as cholestasis or biliary obstruction.

Gamma-Glutamyl Transferase (GGT)

GGT is highly sensitive to liver damage and is particularly useful in detecting alcohol-induced liver injury. It’s often used in conjunction with AST and ALT to provide a more complete picture of liver health.

Bilirubin

Bilirubin is a byproduct of red blood cell breakdown. Elevated levels can indicate liver dysfunction or bile duct obstruction, often manifesting as jaundice.

Albumin and Total Protein

These tests measure the amount of protein in your blood. Low levels can indicate chronic liver disease, as the liver is responsible for producing many blood proteins.

Prothrombin Time (PT)

This test measures how long it takes for your blood to clot. Prolonged clotting times can indicate liver damage, as the liver produces many clotting factors.

By combining these tests with AST results, healthcare providers can more accurately diagnose liver conditions, assess their severity, and monitor treatment effectiveness.

Managing Elevated AST Levels: Lifestyle Changes and Treatment Options

If your AST levels are elevated, your healthcare provider will work with you to identify the underlying cause and develop an appropriate management plan. Depending on the specific diagnosis, this may involve:

Lifestyle Modifications

  • Reducing or eliminating alcohol consumption
  • Adopting a healthy, balanced diet
  • Increasing physical activity and maintaining a healthy weight
  • Avoiding medications or supplements that may stress the liver

Medical Treatments

Specific treatments will depend on the underlying cause of elevated AST levels. These may include:

  • Antiviral medications for viral hepatitis
  • Immunosuppressants for autoimmune liver diseases
  • Medications to manage complications of cirrhosis
  • Targeted therapies for specific liver conditions

Regular Monitoring

Ongoing monitoring of AST levels and other liver function tests is crucial to assess the effectiveness of treatment and detect any changes in liver health. The frequency of follow-up tests will depend on your specific condition and treatment plan.

Remember, elevated AST levels are often reversible with appropriate treatment and lifestyle changes. Working closely with your healthcare provider and following their recommendations can help improve your liver health and overall well-being.

The Future of Liver Health Assessment: Beyond AST

While AST remains a valuable tool in assessing liver health, ongoing research is exploring new biomarkers and diagnostic techniques to enhance our understanding of liver diseases. Some promising areas include:

Non-Invasive Imaging Techniques

Advanced imaging methods like transient elastography (FibroScan) and magnetic resonance elastography (MRE) are becoming increasingly important in assessing liver fibrosis and cirrhosis without the need for invasive biopsies.

Novel Biomarkers

Researchers are investigating new blood-based markers that may offer more specific or sensitive detection of liver damage. These include markers of fibrosis, such as enhanced liver fibrosis (ELF) score, and markers of inflammation like cytokeratin-18 fragments.

Genetic Testing

Advances in genetic testing are helping to identify individuals at higher risk for certain liver diseases, allowing for earlier intervention and personalized treatment approaches.

Artificial Intelligence and Machine Learning

These technologies are being applied to analyze complex datasets, including combinations of traditional liver function tests, novel biomarkers, and imaging results, to improve diagnostic accuracy and predict disease progression.

As our understanding of liver diseases continues to evolve, so too will our diagnostic and monitoring tools. However, traditional tests like AST will likely remain important components of liver health assessment for the foreseeable future.

In conclusion, the AST test, while just one piece of the puzzle, plays a crucial role in evaluating liver health. Understanding its significance, interpretation, and limitations empowers patients and healthcare providers alike in the management of liver conditions. Regular monitoring, lifestyle modifications, and appropriate medical interventions based on AST and other liver function tests can significantly improve outcomes for individuals with liver diseases.

Aspartate Aminotransferase (AST) Test (aka SGOT): High vs. Low Levels

Written by WebMD Editorial Contributors

Medically Reviewed by Jennifer Robinson, MD on May 20, 2021

  • Why Would I Need This Test?
  • How Do I Prepare?
  • What Happens During the Test?
  • What Are the Risks?
  • What Do the Results Mean?
  • Will I Take Other Tests?
  • More

The aspartate aminotransferase (AST) test is a blood test that checks for liver damage. Your doctor might order this test to find out if you have liver disease and to monitor your treatment.

Your liver is an organ that has many important jobs.

It makes a fluid called bile that helps your body digest food. It also removes waste products and other toxins from your blood. It produces proteins, as well as substances that help your blood clot. Alcohol or drug use and diseases such as hepatitis can damage your liver and keep it from doing these jobs.

AST is an enzyme your liver makes. Other organs, like your heart, kidneys, brain, and muscles, also make smaller amounts. AST is also called SGOT (serum glutamic-oxaloacetic transaminase).

Normally, AST levels in your blood are low. When your liver is damaged, it puts more AST into your blood, and your levels rise.

A high AST level is a sign of liver damage, but it can also mean you have damage to another organ that makes it, like your heart or kidneys. That’s why doctors often do the AST test together with tests of other liver enzymes.

Your doctor can order an AST test if you have symptoms of liver damage, such as:

  • Yellow skin or eyes, called jaundice
  • Tiredness
  • Weakness
  • Swollen belly
  • Stomach pain
  • Appetite loss
  • Itchy skin
  • Dark-colored urine
  • Light-colored poop
  • Swelling in your legs and ankles
  • Bruises

Other reasons to have this test:

  • You’ve been exposed to the hepatitis virus.
  • You drink a lot of alcohol.
  • You take medicine that’s known to damage the liver.
  • You have a family history of liver disease.
  • You have obesity.
  • You have diabetes or metabolic syndrome.
  • You’ve had nonalcoholic fatty liver disease.

Your doctor might also want you to get this test to see if treatments you take for liver disease are working.

The AST test is also part of a comprehensive metabolic panel — a blood test your doctor does as part of a routine exam.

You don’t need any special preparation for the ALT test.

Tell your doctor what drugs or supplements you take. Some medicines can affect the results of this test.

A nurse or lab tech will take a sample of your blood — usually from a vein in your arm. They will first tie a band around the upper part of your arm to make your vein fill with blood and swell up. Then they will clean an area on your arm with an antiseptic and put a needle in one of your veins. Your blood will go into a vial or tube.

The blood test should only take a couple of minutes. After your blood is drawn, the lab tech will take off the band and pull out the needle. They’ll put a piece of gauze and a bandage where the needle went in to stop the bleeding.

The AST blood test is safe. Risks are usually minor, and can include:

  • Bleeding
  • Bruising
  • Infection
  • Pain when the needle is inserted
  • Fainting or feeling dizzy

You should have the results in about a day. They are given in units per liter (units/L). Normal ranges are:

  • Males: 10 to 40 units/L
  • Females: 9 to 32 units/L

Your exact range may depend on which lab your doctor uses. Talk with them about the specifics of your case.

Higher-than-normal AST levels can be caused by:

  • Chronic (ongoing) hepatitis
  • Cirrhosis (long-term damage and scarring of the liver)
  • Blockage in the bile ducts that carry digestive fluid from the liver to the gallbladder and intestine
  • Liver cancer

Very high AST levels can be caused by:

  • Acute viral hepatitis
  • Damage to the liver from drugs or other toxic substances
  • A blockage in blood flow to the liver

Your doctor might also compare your AST and ALT levels. If you have liver disease, usually your ALT level will be higher than your AST level.

These other conditions not tied to your liver can also raise your AST level:

  • Burns
  • Heart attack
  • Intense exercise
  • Muscle injury
  • Pregnancy
  • Pancreatitis
  • Seizures
  • Surgery

Some diseases or medicines you take can cause a “false positive” result on the AST test. This means your test is positive, even though you don’t have liver damage. Any of these can cause a false positive result:

  • Diabetic ketoacidosis (Your body can’t make enough insulin, which helps sugar enter your cells.)
  • Some antibiotics, such as erythromycin estolate or para-aminosalicylic acid (Paser)

AST is usually done as part of a group of liver function tests called a liver panel. It’s often ordered with a test for alanine aminotransferase (ALT), another liver enzyme.

ALT is more accurate than AST at detecting liver disease. It can more accurately show whether the problem is in your liver or in another part of your body, like your heart or muscles.

Your doctor can compare the amount of ALT to AST in your blood to find out whether you have liver damage or a problem with another organ, such as your heart.

Your doctor might also do other tests of enzymes and proteins your liver makes, such as:

  • Alkaline phosphatase (ALP)
  • Bilirubin
  • Total protein

Talk with your doctor to make sure you understand all of your liver test results. Also find out how these results might affect your treatment.

Top Picks

Aspartate Aminotransferase (AST) Test (aka SGOT): High vs.

Low Levels

Written by WebMD Editorial Contributors

Medically Reviewed by Jennifer Robinson, MD on May 20, 2021

  • Why Would I Need This Test?
  • How Do I Prepare?
  • What Happens During the Test?
  • What Are the Risks?
  • What Do the Results Mean?
  • Will I Take Other Tests?
  • More

The aspartate aminotransferase (AST) test is a blood test that checks for liver damage. Your doctor might order this test to find out if you have liver disease and to monitor your treatment.

Your liver is an organ that has many important jobs.

It makes a fluid called bile that helps your body digest food. It also removes waste products and other toxins from your blood. It produces proteins, as well as substances that help your blood clot. Alcohol or drug use and diseases such as hepatitis can damage your liver and keep it from doing these jobs.

AST is an enzyme your liver makes. Other organs, like your heart, kidneys, brain, and muscles, also make smaller amounts. AST is also called SGOT (serum glutamic-oxaloacetic transaminase).

Normally, AST levels in your blood are low. When your liver is damaged, it puts more AST into your blood, and your levels rise.

A high AST level is a sign of liver damage, but it can also mean you have damage to another organ that makes it, like your heart or kidneys. That’s why doctors often do the AST test together with tests of other liver enzymes.

Your doctor can order an AST test if you have symptoms of liver damage, such as:

  • Yellow skin or eyes, called jaundice
  • Tiredness
  • Weakness
  • Swollen belly
  • Stomach pain
  • Appetite loss
  • Itchy skin
  • Dark-colored urine
  • Light-colored poop
  • Swelling in your legs and ankles
  • Bruises

Other reasons to have this test:

  • You’ve been exposed to the hepatitis virus.
  • You drink a lot of alcohol.
  • You take medicine that’s known to damage the liver.
  • You have a family history of liver disease.
  • You have obesity.
  • You have diabetes or metabolic syndrome.
  • You’ve had nonalcoholic fatty liver disease.

Your doctor might also want you to get this test to see if treatments you take for liver disease are working.

The AST test is also part of a comprehensive metabolic panel — a blood test your doctor does as part of a routine exam.

You don’t need any special preparation for the ALT test.

Tell your doctor what drugs or supplements you take. Some medicines can affect the results of this test.

A nurse or lab tech will take a sample of your blood — usually from a vein in your arm. They will first tie a band around the upper part of your arm to make your vein fill with blood and swell up. Then they will clean an area on your arm with an antiseptic and put a needle in one of your veins. Your blood will go into a vial or tube.

The blood test should only take a couple of minutes. After your blood is drawn, the lab tech will take off the band and pull out the needle. They’ll put a piece of gauze and a bandage where the needle went in to stop the bleeding.

The AST blood test is safe. Risks are usually minor, and can include:

  • Bleeding
  • Bruising
  • Infection
  • Pain when the needle is inserted
  • Fainting or feeling dizzy

You should have the results in about a day. They are given in units per liter (units/L). Normal ranges are:

  • Males: 10 to 40 units/L
  • Females: 9 to 32 units/L

Your exact range may depend on which lab your doctor uses. Talk with them about the specifics of your case.

Higher-than-normal AST levels can be caused by:

  • Chronic (ongoing) hepatitis
  • Cirrhosis (long-term damage and scarring of the liver)
  • Blockage in the bile ducts that carry digestive fluid from the liver to the gallbladder and intestine
  • Liver cancer

Very high AST levels can be caused by:

  • Acute viral hepatitis
  • Damage to the liver from drugs or other toxic substances
  • A blockage in blood flow to the liver

Your doctor might also compare your AST and ALT levels. If you have liver disease, usually your ALT level will be higher than your AST level.

These other conditions not tied to your liver can also raise your AST level:

  • Burns
  • Heart attack
  • Intense exercise
  • Muscle injury
  • Pregnancy
  • Pancreatitis
  • Seizures
  • Surgery

Some diseases or medicines you take can cause a “false positive” result on the AST test. This means your test is positive, even though you don’t have liver damage. Any of these can cause a false positive result:

  • Diabetic ketoacidosis (Your body can’t make enough insulin, which helps sugar enter your cells.)
  • Some antibiotics, such as erythromycin estolate or para-aminosalicylic acid (Paser)

AST is usually done as part of a group of liver function tests called a liver panel. It’s often ordered with a test for alanine aminotransferase (ALT), another liver enzyme.

ALT is more accurate than AST at detecting liver disease. It can more accurately show whether the problem is in your liver or in another part of your body, like your heart or muscles.

Your doctor can compare the amount of ALT to AST in your blood to find out whether you have liver damage or a problem with another organ, such as your heart.

Your doctor might also do other tests of enzymes and proteins your liver makes, such as:

  • Alkaline phosphatase (ALP)
  • Bilirubin
  • Total protein

Talk with your doctor to make sure you understand all of your liver test results. Also find out how these results might affect your treatment.

Top Picks

Aspartate aminotransferase (AST, AST): norm and interpretation

Aspartate aminotransferase (AST, AST ) is an enzyme involved in biochemical processes inside cells. AST accelerates the transfer of amino groups from aspartate (and ALT from alanine, respectively) in the Krebs cycle, which is a key step in the respiration process for all cells. Note that AST performs its functions together with vitamin B 6 although AST is less sensitive to a decrease in the content of B 6 in the body than ALT . By the way, this is the reason why in patients with alcoholic liver disease the concentration of ALT in the blood decreases more significantly than AST , which contributes to an increase in the ratio of AST / ALT , because the systematic use of alcohol significantly reduces the content of vitamin B 6 in the blood.

Both aminotransferases are concentrated in liver tissues, however AST is also present in the heart, skeletal muscle, kidney, brain, and erythrocytes. In the liver, ALT is concentrated exclusively in the cellular cytoplasm, while AST is found in the cytosol and mitochondria. The circulatory half-life is about 47 hours for ALT and about 17 hours for AST .

To assess the change in level AST use the classification:

  • Soft change – an increase of less than 5 times the maximum allowable limit,
  • Moderate change – 5 to 10 times normal,
  • Marked change – more than 10 times normal.

However, given the blurring of the boundary between mild and moderate changes, they are considered one group.

The norm for children and adolescents is somewhat different from that for adults:

9 0071

Age 73 0–5 days up to 97.0
5 days – 6 months up to 77.0
6 – 12 months up to 82.0
1-3 years up to 48.0
3-6 years old up to 36.0
6-12 years old tires) to 25.0
12–17 years (men) to 29. 0

AST is inside the cells, and only a small part of it is normal is in the blood. When tissues rich in this enzyme are damaged, it enters the bloodstream, which is detected by laboratory methods. Abrupt changes in the content of aspartate aminotransferase occur with damage to the heart muscle – myocardium (for example, with myocardial infarction). The concentration of this enzyme in the blood of 93−98% of patients with myocardial infarction increased. In this case, AST increases in serum after 6-8 hours, it reaches its maximum concentration after 24-36 hours and decreases to a normal level by the 5-6th day. An increase in the area of ​​the heart muscle affected by a heart attack (repeated heart attack) leads to the appearance of a second cycle of increasing the concentration of aspartate aminotransferase . Sometimes the activity of AST increases even before the appearance of electrocardiographic signs of myocardial infarction, and the absence of a decrease in its level after the 3rd–4th day of the disease is considered an unfavorable sign.

Patients with a marked increase in aminotransferase levels (greater than 10-fold) are usually diagnosed with acute liver disease. However, data for a number of patients with acute liver injury caused by viral hepatitis suggest that the most sensitive and specific threshold level of aminotransferases for detecting acute lesions lies within the moderate range (5 to 10 times normal). In cases of acute viral hepatitis, the level of AST typically peaks before jaundice develops and gradually decreases thereafter; in parallel, the level of bilirubin in the blood serum increases. However, jaundice occurs in about 70% of cases of acute hepatitis A, 33% -50% of cases of acute hepatitis B and 20% -33% of cases of acute hepatitis C. The entire spectrum of viral hepatitis (A, B, C, D and E) can be responsible for the marked increase in level AST and ALT , although the increase associated with hepatitis C tends to be more modest than that associated with hepatitis A or B.

When AST and ALT are found to be elevated and risk factors ( for example, travel to an area affected by hepatitis infections) or clinical symptoms, check for hepatitis A and B IgM antibodies, hepatitis B surface antigens, and hepatitis C antibodies, and, if necessary, use polymerase chain reaction (PCR) methods for these viruses .

In addition, other viruses than hepatitis viruses, such as Epstein-Barr virus or cytomegalovirus, as well as autoimmune, extrahepatic and congenital causes, affect the increase in the level of AST . Autoimmune hepatitis can cause both moderate and marked increases in AST and ALT levels. Finally, 25% of patients with AST levels greater than 10 times normal may have acute biliary obstruction, as evidenced by a peak aminotransferase level (more than 50 times normal for 1-2% of patients). In this case, the final diagnosis is confirmed by ultrasound and specific pain in the patient.

Minimal or slight increase in the level of aminotransferases is the most common change in the biochemical analysis of blood. If such an increase is detected in a patient, it is recommended to re-analyze to rule out laboratory error and verify the stability of the increase in the level of AST and / or ALT . For example, chronic hepatitis C infection is characterized by aminotransferase levels fluctuating near the upper limit of normal. For patients taking drugs that are toxic to the liver and for the group of patients who consume alcohol, confirmatory control of aminotransferase levels can be carried out only after cessation of alcohol or drug use.

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of minor changes in serum levels of AST and ALT in developed countries. As in chronic viral hepatitis, the AST/ALT ratio exceeds 1, which is observed in 61% of patients with advanced liver tissue fibrosis and in 24% of patients with no or initial fibrosis. Suspicion of non-alcoholic fatty liver disease is increased in the presence of risk factors, which include obesity, diabetes, hyperlipemia, and hypertension, although the disease may occur in patients without these factors.

With angina, the content of AST , as a rule, remains within the normal range, sometimes it increases slightly in the first 24 hours after an attack. A moderate increase in the content of aspartate aminotransferase is observed in patients with liver metastases and cirrhosis.

In practice, the simultaneous determination of the activity of AST and alanine aminotransferase (ALT, ALT) in the blood is widely used, since it carries much more information about the disease and its nature and allows predicting the outcome of the disease. There is a de Ritis coefficient, that is, the ratio AST / ALT , normally equal to 1.33 . In liver diseases, the de Ritis coefficient is below normal, and in heart diseases it is higher.

Similar to ALT , blood levels of AST may indicate the risk of death within the next decade. There may be several mechanisms by which AST and ALT may be associated with an increased risk of death. First, aminotransferases, being markers of serious liver disease, indicate the risk of mortality from liver disease. Second, aminotransferases, especially ALT , are also markers of cardiovascular disease, which may increase the risk of death. According to studies ALT was associated with the risk of cardiovascular disease among patients without viral hepatitis or excessive alcohol consumption. AST is also elevated in patients with acute myocardial injury or congestive heart failure. Third, an increase in aminotransferase levels may indicate comorbidities that increase the risk of death. For example, chronic alcohol consumption is one of the most common causes of increased AST and ALT . Finally , aminotransferases can be elevated in various types of chronic diseases not related to the liver or cardiovascular diseases, such as muscle and thyroid diseases.

Lactate dehydrogenase (LDH) – indications, norm, blood test

RU / ENG / UA

Lactate dehydrogenase (LDH) is a glycolytic enzyme involved in one of the final stages of glucose conversion (catalysis of the interconversion of pyruvate and lactate).

Catalyzes the reversible oxidation of L-lactate to pyruvate. Lactate dehydrogenase is a cytosolic zinc-containing enzyme. Its concentration inside the cells is much higher than in the blood serum. The enzyme is widely distributed in the human body. According to the degree of decrease in enzyme activity, organs and tissues can be arranged in the following order: kidneys, heart, skeletal muscles, pancreas, spleen, liver, lungs, blood serum.

With age, LDH activity gradually decreases, so the serum activity of the enzyme is higher in children. LDH in the cytoplasm of cells and blood serum is represented by 5 isoenzymes: LDH1, LDH2, LDH3, LDH4, LDH5. Indicators of the total activity of LDH depend on the method of study: 1) kinetic, based on the optical Warburg test, and 2) the end point method. Therefore, in the dynamics of the study, it is recommended to conduct on the basis of one laboratory using the same method. An increase in the activity of lactate dehydrogenases under physiological conditions is noted after intense physical exertion, in newborns, pregnant women.

Diagnosis of lactate dehydrogenase

In patients with myocardial infarction, LDH activity in blood serum increases after 8-10 hours after the onset of the attack, reaching a maximum after 24-28 hours, remains increased during the first week of the disease, normalizing by 8-9 days. Usually the level of LDH exceeds the norm by 3 to 5 times, but there may be a 10-fold increase. The total activity of serum LDH remains elevated twice as long as the activity of other enzymes (determination of creatine kinase-MB and creatine kinase is valuable for diagnosing a heart attack in the early stages).

The value of this test is especially great in unclear cases of the disease, with an atypical clinical and electrocardiographic picture of myocardial infarction. The level of lactate dehydrogenases can be moderately increased in myocarditis and heart failure with congestion in the liver. In pericarditis and angina pectoris, LDH activity does not increase.

An increase in serum LDH activity is observed with hemolysis of any origin, anemia (hemolytic, pernicious, sickle cell, megaloblastic).

In cholelithiasis without obstruction of the bile ducts, there was no increase in LDH activity, while in patients with obstructive jaundice due to neoplasms, biliary cirrhosis, with tumors of the pancreas, it is sharply increased. The same is observed in bile peritonitis, when the liver is involved in the pathological process.

Particularly high levels of enzyme activity are associated with Hodgkin’s disease and malignant diseases of the abdomen and lungs. A moderate increase in LDH is observed in leukemia. Increased enzyme concentrations are found in patients with progressive muscular dystrophy, especially in the early and intermediate stages of the disease. Elevated LDH levels are noted in pulmonary embolism.

Recently, many cases of low LDH activity in blood serum have been described. There are two groups of reasons: 1) the presence of an inhibitor in the serum (plasma) of the blood; 2) genetic disorders. Indeed, in the blood serum of even practically healthy adults there is a thermodependent inhibitor, the presence of which reduces the activity of LDH. IgG, IgA, IgM act as an inhibitor of blood enzyme activity.

Lactate dehydrogenase (LDH) test indications

  1. Myocardial infarction (differential diagnosis and monitoring)
  2. Tumors
  3. Anemias accompanied by hemolysis
  4. Test preparation: fasting blood draw

Examination

Examination material: blood serum (avoid hemolysis, as a falsely high result is possible!)

Method of determination: kinetic (IFCC)

Units of measurement: U/l

Reference values (norm Lactate dehydrogenase (LDH))

Age and gender Lactate dehydrogenase norm
up to 6 months < 975 U/l
7 – 12 months < 1100 U/l
1 – 3 years < 850 U/l
4 – 6 years < 615 U/l
men 7 – 12 years old < 764 U/l
women 7 – 12 years old < 580 U/l
men 13 – 17 years old < 683 U/l
women 13 – 17 years old < 436 U/l
over 17 years old 207 – 414 U/l

Increase in lactate dehydrogenase (LDH) values ​​

Increase in lactate dehydrogenase (LDH) values ​​in men, women and children accompanies any pathological processes that are accompanied by cell destruction and loss of cytoplasm:

  1. Myocardial infarction
  2. Lung infarction
  3. Hemolysis, traumatic shock, extensive burns, extreme hypothermia, hypoxia, etc.
  4. Diseases of the blood system (hemolytic, pernicious, megaloblastic and sickle cell anemia, acute leukemia)
  5. Malignant tumors of various organs
  6. Skeletal muscle diseases (trauma, atrophy)
  7. Kidney pathology (pyelonephritis, glomerulonephritis, kidney infarction, etc.)
  8. Liver pathology (obstructive jaundice, viral and toxic hepatitis, liver cirrhosis)
  9. Acute pancreatitis

The cost of a blood test for the content of gamma-glutamyltransferase

A blood test for the content of lactate dehydrogenase costs 35 UAH. It is carried out within 1-2 days. The cost of taking material for research is paid separately (15 – 25 UAH).

You can get full information about the service from our laboratory doctor.

Medical equipment of our laboratory.

Consultation of a laboratory doctor

Reviews

Currently I am a resident of the Crimea, I learned about the unique methods of treatment in the Clinic, I came here with problematic. .. !

I came to the CDC with pain in the joints, severe varicose veins, complaints about the work of the stomach.
After the…

It so happened that I was already falling off my feet. I had problems with the thyroid gland, my bones hurt a lot, …

I have been sick for a long time. The joints are very sore, the thyroid gland is worried. The joints hurt both under load and in the state…

I have worked as a teacher at the Medical Academy for 35 years, I have been suffering from rheumatoid arthritis for more than 10 years….

I ended up in a clinic with problems of the pancreas. Having passed the diagnostics and the course of treatment, I was satisfied and…

I want to express my heartfelt gratitude to Yuri Nikolaevich Kulikovich for the creation of such a clinic, for the kindness…

We came from far away, and we were very touched by the care and attention that surrounded us in the Clinic. Thank you very much…

Complaints about the musculoskeletal system forced me to go to the clinic, my knees and hips hurt. .. for the help rendered to me in the treatment, in…

The first thing that impressed me was the fashionableness, but this is a shell. The most important thing is that during the treatment I…

I am very grateful to the people who work here for the kindness and warmth that they radiate, for the attitude that…

I sincerely thank all the staff of the clinic for the warm professional attitude towards the patient, for…

I am a health worker with 17 years of experience. I work in the Central District Hospital of Verkhnedneprovsk. Until today in private…

I would like to express my sincere gratitude for the sensitive attitude and professional treatment of everything…

Thank you from the bottom of my heart, Dr. Kulikovich Yu.N., for the creation of a modern center of domestic medicine…

I am deeply grateful to Comrade Kulikovich Yuri Nikolaevich and the medical staff for their sensitivity and constant…

The doctor chooses the method of treatment in accordance with the nature of the disease, – the healer in accordance with the nature.