What are AST and ALT enzymes. How do these liver enzymes indicate liver health. What causes abnormal AST and ALT levels. When should you get tested for liver enzymes. How are AST and ALT tests performed. What do high or low AST and ALT results mean. How are liver enzyme abnormalities treated.

The Importance of AST and ALT in Liver Function Assessment

Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are crucial enzymes primarily found in the liver. These enzymes play a vital role in amino acid metabolism and are key indicators of liver health. When liver cells are damaged, AST and ALT are released into the bloodstream, making their blood levels valuable markers for detecting liver problems.

AST is also present in other organs like the heart, muscles, and kidneys, while ALT is more specific to the liver. This makes ALT a more reliable indicator of liver damage. However, both enzymes are typically measured together to provide a comprehensive assessment of liver function.

Why are AST and ALT tests important?

• Early detection of liver disease
• Monitoring progression of existing liver conditions
• Assessing the effectiveness of treatments
• Screening for potential liver damage from medications or alcohol use

Normal Ranges for AST and ALT: What Do They Mean?

Understanding the normal ranges for AST and ALT is crucial for interpreting test results. However, it’s important to note that these ranges can vary slightly depending on the laboratory and the specific testing method used.

Typical normal ranges for adults:

• AST: 5 to 40 units per liter (U/L)
• ALT: 7 to 56 U/L

These ranges may differ for children, elderly individuals, and pregnant women. It’s always best to consult with a healthcare provider for interpretation of your specific results.

Can AST and ALT levels be too low?

While much attention is given to elevated liver enzyme levels, low levels of AST and ALT are generally not a cause for concern. In rare cases, extremely low levels might indicate malnutrition or certain vitamin deficiencies, but this is uncommon. The focus is typically on elevated levels as indicators of potential liver damage or disease.

Causes of Elevated AST and ALT Levels

Elevated AST and ALT levels can be caused by various factors, ranging from temporary conditions to serious liver diseases. Understanding these causes can help in proper diagnosis and treatment.

Common causes of high AST and ALT:

1. Viral hepatitis (A, B, C)
2. Alcoholic liver disease
3. Non-alcoholic fatty liver disease (NAFLD)
4. Medications (e.g., acetaminophen, statins)
5. Autoimmune hepatitis
6. Cirrhosis
7. Liver cancer
8. Muscle damage or intense exercise (particularly affecting AST)
9. Heart problems (can elevate AST)
10. Obesity

It’s important to note that temporary elevations can occur due to factors like recent alcohol consumption or strenuous exercise. This is why healthcare providers often recommend retesting to confirm persistent elevations before making a diagnosis.

Symptoms Associated with Abnormal Liver Enzyme Levels

While elevated AST and ALT levels themselves don’t cause symptoms, the underlying liver conditions causing these elevations may present various signs and symptoms. Recognizing these symptoms can prompt timely medical attention and testing.

Common symptoms of liver problems include:

• Fatigue and weakness
• Jaundice (yellowing of skin and eyes)
• Abdominal pain or swelling
• Nausea and vomiting
• Loss of appetite
• Dark urine
• Pale or clay-colored stools
• Itchy skin
• Easy bruising or bleeding

It’s crucial to understand that liver disease can progress silently, often without noticeable symptoms in its early stages. This underscores the importance of routine liver function tests, especially for individuals at higher risk of liver problems.

The AST/ALT Ratio: A Valuable Diagnostic Tool

The ratio of AST to ALT can provide additional insights into the nature and severity of liver damage. This ratio is particularly useful in distinguishing between different types of liver diseases and assessing their progression.

How is the AST/ALT ratio interpreted?

• AST/ALT ratio < 1: Typical in viral hepatitis and non-alcoholic fatty liver disease
• AST/ALT ratio > 2: Often indicates alcoholic liver disease
• AST/ALT ratio > 1 but < 2: May suggest cirrhosis or more advanced liver disease

While the AST/ALT ratio is a valuable tool, it should always be interpreted in conjunction with other clinical findings and test results. Factors such as medication use, muscle damage, and other health conditions can influence this ratio.

When is the AST/ALT ratio most useful?

The AST/ALT ratio is particularly helpful in:

1. Differentiating alcoholic liver disease from other forms of liver damage
2. Assessing the severity and progression of chronic liver diseases
3. Predicting the likelihood of fibrosis or cirrhosis in patients with chronic hepatitis

When Should You Get Tested for AST and ALT?

Knowing when to get tested for liver enzymes is crucial for early detection and management of liver problems. While routine health check-ups often include these tests, there are specific situations where AST and ALT testing is particularly important.

Indications for AST and ALT testing:

• As part of a routine health screening
• When experiencing symptoms of liver disease
• Monitoring known liver conditions
• Before starting medications that can affect the liver
• For individuals with risk factors for liver disease (e.g., heavy alcohol use, obesity, diabetes)
• After exposure to hepatitis viruses
• To evaluate unexplained fatigue or weakness

It’s important to follow your healthcare provider’s recommendations for testing frequency, especially if you have ongoing liver concerns or are at higher risk for liver problems.

The Process of AST and ALT Testing: What to Expect

Understanding the testing process can help alleviate any anxiety and ensure proper preparation for accurate results. AST and ALT tests are typically performed as part of a comprehensive metabolic panel or liver function tests.

Steps in AST and ALT testing:

1. Preparation: Fasting for 8-12 hours may be required, depending on the specific tests ordered.
2. Blood draw: A small sample of blood is taken from a vein, usually in the arm.
3. Laboratory analysis: The blood sample is sent to a lab for analysis.
4. Results: Typically available within a few days.

The test itself is quick and relatively painless, with minimal risks. Some people may experience slight bruising or discomfort at the site of the blood draw.

Are there any special preparations needed?

While fasting is often recommended, it’s essential to follow your healthcare provider’s specific instructions. Certain medications, supplements, and even intense exercise can affect AST and ALT levels, so it’s important to inform your provider of any such factors before the test.

Interpreting High AST and ALT Results: What Do They Mean?

Elevated AST and ALT levels can indicate various liver conditions, but the degree of elevation and the pattern of increase can provide valuable diagnostic clues. Understanding these patterns helps healthcare providers determine the most likely causes and appropriate next steps.

Mild elevations (less than 5 times the upper limit of normal):

• Non-alcoholic fatty liver disease (NAFLD)
• Chronic hepatitis
• Medication-induced liver injury
• Alcohol-related liver disease

Moderate elevations (5-15 times the upper limit of normal):

• Acute viral hepatitis
• Autoimmune hepatitis
• Alcoholic hepatitis

Severe elevations (more than 15 times the upper limit of normal):

• Acute liver injury (e.g., acetaminophen overdose)
• Ischemic hepatitis (reduced blood flow to the liver)
• Acute viral hepatitis

It’s crucial to remember that AST and ALT levels alone don’t provide a definitive diagnosis. Additional tests, imaging studies, and sometimes liver biopsies may be necessary to determine the underlying cause of elevated liver enzymes.

Treatment Approaches for Abnormal AST and ALT Levels

The treatment for abnormal AST and ALT levels depends on the underlying cause. In many cases, addressing the root cause can lead to normalization of liver enzyme levels. However, some chronic conditions may require ongoing management to prevent further liver damage.

Common treatment approaches include:

1. Lifestyle modifications:
   • Reducing or eliminating alcohol consumption
   • Adopting a healthy diet and exercise routine
   • Weight loss for individuals with NAFLD
2. Medication management:
   • Discontinuing or changing medications that may be causing liver damage
   • Antiviral treatments for viral hepatitis
   • Immunosuppressants for autoimmune hepatitis
3. Treatment of underlying conditions:
   • Managing diabetes and other metabolic disorders
   • Addressing heart conditions that may be affecting the liver
4. Liver-protective medications:
   • Use of hepatoprotective agents in certain cases
5. Regular monitoring:
   • Periodic AST and ALT testing to track progress and adjust treatment as needed

In cases of severe liver damage or failure, more intensive interventions such as liver transplantation may be necessary. The key to successful management is early detection and appropriate treatment tailored to the individual’s specific condition and needs.

Can lifestyle changes alone normalize AST and ALT levels?

In many cases, especially for conditions like NAFLD or mild alcoholic liver disease, lifestyle modifications can significantly improve liver health and normalize AST and ALT levels. However, the effectiveness of lifestyle changes depends on the underlying cause and the extent of liver damage. It’s essential to work closely with a healthcare provider to develop an appropriate treatment plan and monitor progress.

Prevention Strategies for Maintaining Healthy Liver Enzyme Levels

Maintaining healthy AST and ALT levels is crucial for overall liver health and can prevent the development of serious liver conditions. While some risk factors for liver disease are not modifiable, there are several strategies individuals can employ to protect their liver and maintain normal enzyme levels.

Key prevention strategies include:

• Limiting alcohol consumption: Excessive alcohol intake is a leading cause of liver damage. Adhering to recommended guidelines or abstaining completely can significantly reduce the risk of alcoholic liver disease.
• Maintaining a healthy weight: Obesity is a major risk factor for non-alcoholic fatty liver disease. Achieving and maintaining a healthy body weight through diet and exercise can help prevent liver problems.
• Eating a balanced diet: A diet rich in fruits, vegetables, whole grains, and lean proteins supports liver health. Limiting processed foods, saturated fats, and added sugars is beneficial.
• Regular exercise: Physical activity helps maintain a healthy weight and can improve liver function. Aim for at least 150 minutes of moderate-intensity exercise per week.
• Avoiding hepatotoxic substances: Be cautious with medications, supplements, and environmental toxins that can harm the liver. Always follow dosage instructions and consult healthcare providers about potential liver risks.
• Practicing safe behaviors: Prevent exposure to hepatitis viruses by practicing safe sex, avoiding sharing needles, and getting vaccinated against hepatitis A and B when recommended.
• Managing chronic conditions: Properly controlling conditions like diabetes, high cholesterol, and hypertension can help prevent liver complications.
• Regular health check-ups: Routine medical examinations, including liver function tests, can help detect and address liver issues early.

By incorporating these preventive measures into daily life, individuals can significantly reduce their risk of developing liver problems and maintain healthy AST and ALT levels. Remember, liver health is an essential component of overall well-being, and proactive steps can make a substantial difference in long-term health outcomes.

How effective are liver supplements in maintaining normal AST and ALT levels?

While some liver supplements claim to support liver health and function, their effectiveness in maintaining normal AST and ALT levels is often debated. Some natural compounds, such as milk thistle and N-acetyl cysteine, have shown potential benefits in certain liver conditions. However, it’s important to note that:

1. Scientific evidence for many liver supplements is limited or inconclusive.
2. Supplements are not regulated as strictly as medications and may vary in quality and potency.
3. Some supplements can interact with medications or cause liver damage themselves.

Therefore, it’s crucial to consult with a healthcare provider before starting any liver supplements. In most cases, lifestyle modifications and addressing underlying health issues are more effective and safer approaches to maintaining liver health than relying on supplements alone.

AST Test: MedlinePlus Medical Test

What is an AST Test?

AST (aspartate aminotransferase) is an enzyme that is found mostly in the liver, but it’s also in muscles and other organs in your body. When cells that contain AST are damaged, they release the AST into your blood. An AST blood test measures the amount of AST in your blood. The test is commonly used to help diagnose liver damage or disease.

Other names: SGOT test, serum glutamic oxaloacetic transaminase test; aspartate transaminase test

What is it used for?

An AST blood test is often part of a routine blood screening to check the health of your liver. The test may help diagnose or monitor liver problems. It may also help diagnose other health conditions.

Why do I need an AST blood test?

You may get an AST blood test as part of your routine checkup or if you have symptoms of liver damage. These may include:

• Nausea and vomiting
• Lack of appetite
• Fatigue
• Weakness
• Jaundice, a condition that causes your skin and eyes to turn yellow
• Swelling and/or pain in your abdomen (belly)
• Swelling in your ankles and legs
• Dark-colored urine (pee) and/or light-colored stool (poop)
• Frequent itching

Even if you don’t have symptoms, your health care provider may order an AST blood test if you’re more likely to develop liver disease because of:

• A family history of liver disease
• Alcohol use disorder
• Obesity
• Diabetes
• Taking certain medicines that can cause liver damage
• Hepatitis or exposure to hepatitis

What happens during an AST blood test?

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for the test?

You don’t need any special preparations for an AST blood test. But an AST test is usually ordered with other blood tests. You usually need to fast (not eat or drink) for up to 12 hours before these tests. Your provider will let you know if there are any special instructions to follow.

Are there any risks to the test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

What do the results mean?

High levels of AST in the blood may be a sign of hepatitis, cirrhosis, mononucleosis, or other liver diseases. High AST levels may also be a sign of heart problems or pancreatitis.

If your results are not in the normal range, it doesn’t always mean that you have a medical condition that needs treatment. Many things can affect your results, such as certain medicines and your age, sex, and diet. To learn what your results mean, talk with your provider.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about an AST blood test?

Your health care provider may order an ALT blood test with your AST blood test. ALT stands for alanine transaminase, which is another type of liver enzyme. If you have high levels of AST and/or ALT, it may mean that you have some type of liver damage.

You may also have an AST test as part of a group of liver function tests that measure ALT, and other enzymes, proteins, and substances in the liver.

References

1. American Liver Foundation. [Internet]. New York: American Liver Foundation; c2017. Diagnosing Liver Disease – Liver Biopsy and Liver Function Tests; [updated 2020 Feb 17; cited 2022 Feb 14]; [about 3 screens]. Available from: https://liverfoundation. org/for-patients/about-the-liver/diagnosing-liver-disease/
2. Hinkle J, Cheever K. Brunner & Suddarth’s Handbook of Laboratory and Diagnostic Tests. 2nd Ed, Kindle. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. Aspartate Aminotransferase; p. 68–69.
3. National Heart, Lung, and Blood Institute [Internet]. Bethesda (MD): U.S. Department of Health and Human Services; Blood Tests; [cited 2022 Feb 14]; [about 15 screens]. Available from: https://www.nhlbi.nih.gov/health-topics/blood-tests
4. Testing.com [Internet]. Seattle (WA).: OneCare Media; c2022. Aspartate Aminotransferase: The Test; [modified 2021 Nov 9; cited 2022 Feb 14; [about 14 screens]. Available from: https://www.testing.com/test/aspartate-aminotransferase-ast/
5. University of Rochester Medical Center [Internet]. Rochester (NY): University of Rochester Medical Center; c2017. Health Encyclopedia: Aspartate Transaminase; [cited 2017 Mar 13]; [about 2 screens]. Available from: https://www. urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=aspartate_transaminase

Aspartate aminotransferase (AST) blood test

Medical Tests 

Definition

The aspartate aminotransferase (AST) blood test measures the level of the enzyme AST in the blood.

Alternative Names

Aspartate aminotransferase; Serum glutamic-oxaloacetic transaminase; SGOT

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

No special preparation is needed.

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

AST is an enzyme found in high levels in the liver, heart, and muscles. It is also found in lesser amounts in other tissues. An enzyme is a protein that causes a specific chemical change in the body.

Injury to the liver results in release of AST into the blood.

This test is mainly done along with other tests (such as ALT, ALP, and bilirubin) to diagnose and monitor liver disease.

Normal Results

The normal range is 8 to 33 U/L.

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different samples. Talk to your health care provider about the meaning of your specific test results.

What Abnormal Results Mean

An increased AST level is often a sign of liver disease. Liver disease is even more likely when the levels of substances checked by other liver blood tests have also increased.

An increased AST level may be due to any of the following:

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• Scarring of the liver (cirrhosis)
• Death of liver tissue
• Heart attack
• Too much iron in the body (hemochromatosis)
• Swollen and inflamed liver (hepatitis)
• Lack of blood flow to the liver (liver ischemia)
• Liver cancer or tumor
• Use of drugs that are toxic to the liver, especially alcohol use
• Mononucleosis (“mono”)
• Muscle disease or trauma
• Swollen and inflamed pancreas (pancreatitis)

AST level may also increase after:

• Burns (deep)
• Heart procedures
• Seizure
• Surgery

Pregnancy and exercise may also cause an increased AST level.

Risks

There is little risk involved with having your blood taken. Veins vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Risks associated with having blood drawn are slight, but may include:

• Fainting or feeling lightheaded
• Excessive bleeding
• Multiple punctures to locate veins
• Hematoma (blood collecting under the skin)
• Infection (a slight risk any time the skin is broken)

References

Chernecky CC, Berger BJ. Aspartate aminotransferase (AST, aspartate transaminase, SGOT) – serum. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:172-173.

Pincus MR, Tierno PM, Gleeson E, Bowne WB, Bluth MH. Evaluation of liver function. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St Louis, MO: Elsevier; 2017:chap 21.

Pratt DS. Liver chemistry and function tests. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 73.

Review Date: 01/26/2019

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. Copyright ©2019 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.

Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Health. Please discuss with your doctor any questions or concerns you may have.

ALT and AST (blood chemistry)

ALT and AST – these abbreviations can often be seen in a blood test for biochemistry. What do they mean? What can they tell the doctor? Vasilisa Vladimirovna Ishchenko, a gastroenterologist at Clinic Expert Kursk, answers our questions.

ALT and AST – these abbreviations can often be seen in a blood test for biochemistry. What do they mean? What can they tell the doctor? Vasilisa Vladimirovna Ishchenko, a gastroenterologist at Clinic Expert Kursk, answers our questions.

– Vasilisa Vladimirovna, what do the abbreviations ALT and AST mean?

– ALT, or alanine aminotransferase, is an endogenous enzyme produced by liver cells – hepatocytes. Its content in blood serum is negligible. The highest concentration of ALT is observed in the liver, so this enzyme is a specific marker of diseases of this organ. In addition, small amounts of ALT can be found in the kidneys, heart muscle, skeletal muscles, and pancreas.

AST, or aspartate aminotransferase, is also an enzyme from the group of transaminases that is involved in amino acid metabolism. It is found mainly in the liver, myocardium, nervous tissue, skeletal muscles, and to a lesser extent in the kidneys, pancreas, spleen, and lung tissue.

When cells are damaged under the influence of infectious or toxic factors, energy metabolism in cells changes. Due to a violation of the permeability of cell membranes, components of the cytoplasm and decayed intracellular structures, including enzymes, enter the blood serum. As a result, the level of ALT and AST in the blood rises. This complex of disorders is called the cytolytic syndrome.

— What will the ALT and AST indicators tell about in a biochemical blood test?

— Normally, the concentration of transaminases and their ratio to each other in the blood plasma are constant values. They reflect the balance of formation and release of these enzymes. In addition, this balance indicates the normal course of the physiological destruction of aged cells (apoptosis). Deviation from the norm of the level of ALT and AST and a change in their ratio is observed in pathological processes.

The degree of increase in the activity of these enzymes allows us to judge the severity of the cytolytic syndrome. However, these indicators do not always indicate the severity of organ damage and do not allow the doctor to judge the prospects for the development of the disease. Therefore, along with the analysis of ALT and AST, specialists usually prescribe a set of laboratory and instrumental examination methods, and also monitor the level of enzymes in dynamics.

— When are these tests recommended?

– Data on the level of ALT and AST may be important for such non-specific symptoms as general weakness, decreased performance, lack of appetite, nausea, vomiting, abdominal pain, flatulence, yellowing of the skin and mucous membranes. These indicators are necessarily determined for the diagnosis of diseases and the assessment of the functioning of the liver.

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— What are the reasons for the increase in ALT and AST in the blood?

– Acute and chronic viral, toxic hepatitis, autoimmune diseases, fermentopathy, liver cirrhosis, tumor processes and liver metastases, infectious mononucleosis, pulmonary embolism, poliomyelitis, malaria, leptospirosis – in many pathological conditions, we observe an increase in the level of these enzymes in blood. Also, ALT and AST levels increase with myocardial infarction. Small short-term changes in their level can be observed during heavy physical exertion.

I would like to note that the ratio between ALT and AST (the so-called de Ritis coefficient) is also an important diagnostic indicator. This coefficient helps us distinguish, for example, viral hepatitis from alcoholic liver damage, myocardial infarction from liver disease.

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— What can cause a decrease in ALT and AST levels in the blood?

– Vitamin B6 deficiency, severe liver cirrhosis, pancreatic pathologies, renal failure (especially in patients on hemodialysis).

— How does the level of ALT and AST in the blood during pregnancy change?

– Since the liver during this period detoxifies the body of not only the mother, but also the fetus, an increase in the level of these enzymes can be observed.

— Vasilisa Vladimirovna, do you need to prepare for the test for ALT and AST? If so, which one?

– Definitely required. Blood from a vein must be taken in the morning on an empty stomach (the last meal 12 hours before the study). On the eve of the test, severe physical exertion, changes in diet, and the use of alcoholic beverages should be avoided. Half an hour before blood sampling, you should also refrain from smoking.

I want to emphasize that the determination of only the level of ALT and AST is not always informative enough, therefore, most often doctors prescribe them in combination with other biochemical indicators.

Would you like to read about other tests? You can find articles about them in our section on laboratory diagnostics

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Interviewed by Sevil Ibraimova

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For information:

Ishchenko Vasilisa Vladimirovna

Graduate of the Medical Faculty of Kursk State Medical University in 2015.

In 2016 she completed her internship in Therapy and underwent retraining in gastroenterology.

Currently holds the position of a gastroenterologist at the “Expert Clinic” Kursk. Conducts reception at the address: st. Karl Liebknecht, 7.

ALT and AST what is it?

ALT ( alanine aminotransferase) and AST (aspartate aminotransferase) – belong to aminotransferase enzymes involved in amino acid metabolism. They are also called liver enzymes. They are found mainly in the cells of the liver and in other organs: pancreas, heart, kidneys, muscle tissue. A small amount of ALT and AST may appear in the blood due to physiological processes. However, in case of liver diseases (infectious or toxic hepatitis, tumor), damage to the liver cells occurs, the permeability of cell membranes is impaired and a large amount of ALT and AST enzymes are released into the blood – as a result, a cytolytic syndrome develops.

ALT and AST transaminases are specific markers of liver disease. Indications for their appointment may be the following:

• Presence of symptoms: nausea, vomiting, abdominal pain, yellowing of the skin and sclera, lethargy.
• laboratory diagnostics of liver diseases: viral hepatitis A, B, C, toxic hepatitis, fatty non-alcoholic liver disease (steatohepatitis), alcoholic liver disease, cirrhosis of the liver.
• Monitoring the dynamics of therapy for liver diseases.

Norms for the content of liver enzymes in the blood:

Age	Men	Women	Units
0-1 years	13-45		U/ml
1-60 years old	10-40	7. 0-35.0
60-90 years old	13.0-40.0	10.0-28.0
Over 90 years old	6.0-38	5.0-24.0

Reasons for increasing ALT, AST (hepatic and extrahepatic)

The level of ALT in acute viral or drug-induced hepatitis can rise 50 times or more. With steatohepatitis and alcoholic liver disease, the increase in ALT is moderate – no more than 5 times. In chronic hepatitis, there is an increase in ALT by about 7 times. In cirrhosis, ALT and AST values ​​increase by 3-5 times, while AST may be higher than ALT.

During pregnancy, a woman’s body experiences an increased load, so there may be a slight increase in transaminases.

Currently, macro-AST-emia syndrome has become known – this is a rare condition in which complexes are formed in the human body from the AST molecule and immunoglobulin. This condition may be hereditary or associated with liver disease. It is characterized by a prolonged and asymptomatic increase in alanine aminotransferase in the blood.

An important diagnostic value is not only an increase in the level of transaminases, but also a decrease. A decrease in ALT and AST below normal indicates end-stage cirrhosis or severe liver damage in hepatitis. This is an extremely unfavorable sign, as it indicates the total destruction of liver cells.