Aspartate Aminotransferase (AST)

The Aspartate Aminotransferase (AST) test contains 1 test with 1 biomarker.

Brief Description: The AST test, also known as Aspartate Aminotransferase or SGOT (Serum Glutamic Oxaloacetic Transaminase), is a blood test that measures the levels of the enzyme AST in the bloodstream. AST is primarily found in liver cells, but it is also present in other organs, such as the heart, muscles, and kidneys. The test helps evaluate the health of the liver and other organs and assists in diagnosing various medical conditions.

Also Known As: Aspartate Aminotransferase Test, Serum Glutamic-Oxaloacetic Transaminase Test, SGOT Test Transaminase, Serum AST Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is an Aspartate Aminotransferase test ordered?

When someone undergoes a standard health examination, an AST test may be requested as part of a full metabolic panel.

When a person exhibits indications and symptoms of a liver problem, an AST test may be ordered along with numerous other tests.

Because many persons with minor liver damage have no signs or symptoms, AST may be ordered alone or in combination with other tests for people who are at an elevated risk for liver disease.

When AST is used to evaluate the effectiveness of treatment for people with liver disease, it may be ordered on a frequent basis during the course of treatment.

What does an Aspartate Aminotransferase blood test check for?

Aspartate aminotransferase is an enzyme found in cells all over the body, but especially in the heart and liver, as well as the kidneys and muscles to a lesser amount. AST levels in the blood are typically low in healthy people. AST is released into the bloodstream when liver or muscle cells are damaged. As a result, AST can be used to detect or monitor liver disease.

The liver is a critical organ found directly behind the rib cage in the upper right side of the abdomen. It is engaged in a variety of vital bodily functions. The liver aids in the digestion of nutrients, creates bile to aid in fat digestion, manufactures numerous vital proteins such as blood clotting factors, and breaks down potentially hazardous compounds into safe substances that the body may utilize or expel.

A variety of disorders can harm liver cells and cause AST levels to rise. The test is most effective in detecting liver damage caused by hepatitis, liver-toxic medications, cirrhosis, or alcoholism. AST, on the other hand, is not particular to the liver and can be elevated in diseases affecting other organs.

Alanine aminotransferase testing is frequently combined with an AST test. When the liver is injured, both of these enzymes become high in the bloodstream. A computed AST/ALT ratio can help distinguish between different types of liver injury and determine whether elevated levels are due to something else, such as a heart or muscle injury.

Lab tests often ordered with an Aspartate Aminotransferase test:

Elevated AST levels can indicate liver damage or disease, but since AST is not exclusive to the liver, it's often used in conjunction with other tests to determine the specific cause of liver injury or to assess other conditions. Here are some tests commonly ordered alongside it:

1. Alanine Aminotransferase (ALT):

   • Purpose: To measure the level of ALT, another liver enzyme.
   • Why Is It Ordered: ALT is more liver-specific than AST. Comparing AST and ALT levels can help differentiate between liver damage and damage to other tissues.

2. Alkaline Phosphatase (ALP):

   • Purpose: To measure the level of ALP, an enzyme related to the bile ducts.
   • Why Is It Ordered: High levels of ALP can indicate blockage of bile ducts, liver injury, or bone diseases.

3. Bilirubin:

   • Purpose: To measure the level of bilirubin, a byproduct of red blood cell breakdown.
   • Why Is It Ordered: Elevated bilirubin levels can indicate liver dysfunction or bile duct obstruction.

4. Gamma-Glutamyl Transferase (GGT):

   • Purpose: To measure GGT, an enzyme involved in bile formation.
   • Why Is It Ordered: Elevated GGT levels can support the diagnosis of liver and bile duct diseases.

5. Complete Blood Count (CBC):

   • Purpose: Provides a broad picture of overall blood health.
   • Why Is It Ordered: To detect signs of anemia or other blood cell abnormalities that might be associated with certain liver conditions.

6. Prothrombin Time (PT)/INR:

   • Purpose: To assess blood clotting function.
   • Why Is It Ordered: Liver damage can affect the production of clotting factors, so this test can be important in assessing liver function.

7. Liver Function Panel:

   • Purpose: A comprehensive assessment of liver health, including AST, ALT, ALP, bilirubin, and albumin.
   • Why Is It Ordered: To provide a broader picture of liver function and help determine the cause of liver injury.

8. Serum Albumin and Total Protein:

   • Purpose: To measure the levels of albumin and total protein in the blood.
   • Why Is It Ordered: To assess liver's ability to synthesize proteins, which can be impaired in liver disease.

9. Hepatitis Serology Test:

   • Purpose: To test for hepatitis A, B, and C, which can cause liver inflammation and damage.
   • Why Is It Ordered: To determine if hepatitis infection is the cause of elevated liver enzymes.

10. Lactate Dehydrogenase (LDH):

    • Purpose: To measure LDH, an enzyme found throughout the body.
    • Why Is It Ordered: To help determine the cause of tissue damage, as LDH can be elevated in various conditions affecting different organs.

These tests, when ordered alongside an Aspartate Aminotransferase test, provide a comprehensive view of liver health and can help diagnose the cause of liver injury, monitor liver disease, and guide treatment. The specific combination of tests will depend on the individual’s symptoms, medical history, and initial test results.

Conditions where an Aspartate Aminotransferase test is recommended:

An AST test is valuable in diagnosing and monitoring various medical conditions, including:

1. Liver Diseases: Hepatitis (viral or autoimmune), cirrhosis, fatty liver, or liver tumors can lead to elevated AST levels.

2. Heart Conditions: AST can be released into the bloodstream during a heart attack or other heart-related issues.

3. Muscle Injuries: Muscle damage or injuries, such as from trauma, strenuous exercise, or certain muscle diseases, can elevate AST levels.

4. Kidney Diseases: Severe kidney infections or damage can cause increased AST levels.

5. Medication Toxicity: Certain medications, toxins, or drugs can lead to elevated AST levels if they cause liver or organ damage.

How does my health care provider use an Aspartate Aminotransferase test?

The aspartate aminotransferase blood test is commonly used to identify liver disease. It is frequently ordered in conjunction with alanine aminotransferase, another liver enzyme, or as part of a liver panel or comprehensive metabolic panel to screen for and/or diagnose liver problems.

Although ALT is more specific for the liver than AST and is more usually elevated than AST, both are regarded to be two of the most significant tests for detecting liver impairment. When AST is directly compared to ALT, an AST/ALT ratio is calculated. This ratio can be used to differentiate between different types of liver disease and hepatic harm from heart or muscle damage.

To assess which type of liver illness is present, AST levels are frequently compared to the results of other tests such as alkaline phosphatase, total protein, and bilirubin.

AST is frequently evaluated to monitor the treatment of people with liver disease, and it can be ordered alone or in combination with other tests.

AST is sometimes used to monitor persons who are receiving potentially hazardous drugs for the liver. If the person's AST levels rise, he or she may be moved to another medicine.

What do my AST test results mean?

Low AST levels in the blood are typical and anticipated.

Acute hepatitis and viral infections are the most common causes of very high AST values. AST values are normally elevated for 1-2 months after acute hepatitis, but they might take up to 3-6 months to recover to normal. AST levels can also be significantly high as a result of exposure to liver-toxic medications or other chemicals, as well as situations that produce reduced blood supply to the liver.

AST values are usually lower in chronic hepatitis, generally less than 4 times normal, and are more likely to be normal than ALT levels. With chronic hepatitis, AST levels typically fluctuate between normal and slightly elevated, so the test may be ordered repeatedly to detect the pattern. Other illnesses of the liver, particularly when the bile ducts are clogged, as well as cirrhosis and certain malignancies of the liver, can cause moderate increases. AST can also rise after a heart attack or a muscular damage, although to a far higher extent than ALT.

The AST test is frequently done in conjunction with the ALT test or as part of a liver panel. See the Liver Panel article for more information on AST values in relation to other liver tests.

The ALT level is usually greater than the AST level in most kinds of liver disease, and the AST/ALT ratio is low. There are a few exceptions: in alcoholic hepatitis, cirrhosis, hepatitis C virus-related chronic liver disease, and the first day or two of acute hepatitis or injury from bile duct obstruction, the AST/ALT ratio is frequently elevated. AST levels are generally substantially higher than ALT after cardiac or muscle injury, and they tend to stay higher than ALT for longer than they do after liver injury.

Understanding Aspartate Aminotransferase (AST) Blood Work: Key Insights and Test Interpretation

When it comes to assessing liver health and function, medical professionals often rely on a range of blood tests. One crucial test is the Aspartate Aminotransferase (AST) blood work. 

AST Blood Work: What is AST? AST, also known as Serum Glutamic Oxaloacetic Transaminase (SGOT), is an enzyme primarily found in various tissues, including the liver, heart, muscles, and kidneys. AST is released into the bloodstream when these organs or tissues are damaged or injured. Therefore, AST blood work serves as an essential indicator of potential health concerns related to these organs.

Interpreting AST Blood Work: AST blood work involves measuring the levels of this enzyme in a blood sample. The results are typically reported as units per liter (U/L). Elevated AST levels may suggest liver damage or diseases such as hepatitis, cirrhosis, or alcohol-related liver injury. However, it is important to note that AST elevation can also be caused by conditions unrelated to the liver, such as heart disease, muscle injury, or certain medications.

Low AST-SGOT Levels: While elevated AST levels are more commonly discussed, it is worth mentioning that low AST-SGOT levels can also provide valuable insights. In some cases, low AST-SGOT levels may indicate deficiencies in vitamin B6 or conditions involving malnutrition or severe liver damage.

Understanding AST in Blood Work: AST is one of the key components measured in routine blood work, especially in liver function panels. The levels of AST can help healthcare providers assess the overall health and functioning of the liver. The AST blood test is a valuable tool for diagnosing liver diseases and monitoring treatment progress.

What to Expect during an AST Blood Test: Getting an AST blood test is a simple and routine procedure. A healthcare professional will draw a small sample of your blood, usually from a vein in your arm. The sample is then sent to a laboratory for analysis. The results are typically available within a few days, and your healthcare provider will discuss and interpret the findings with you.

Conclusion: Aspartate Aminotransferase (AST) blood work plays a crucial role in assessing liver health and diagnosing various conditions. By measuring AST levels in the bloodstream, healthcare professionals can gain valuable insights into liver function and identify potential liver diseases or injuries. If you are undergoing AST blood work, understanding the significance of AST, its interpretation, and what to expect during the test can help you stay informed and actively participate in your healthcare journey.

Most Common Questions About the AST test:

Understanding the AST Test

What is the AST test?

The Aspartate Aminotransferase (AST) test is a blood test that measures the level of the AST enzyme in the blood. AST is found in a variety of tissues, including the liver and heart, and high levels can indicate tissue damage.

Why is the AST test performed?

The AST test is typically used to help diagnose and monitor liver disease, such as hepatitis or cirrhosis. It may also be used to assess the extent of damage following a heart attack.

What are the normal levels of AST in the blood as indicated by the AST test?

Normal AST levels range from 10 to 40 units per liter in adults, but this can vary slightly depending on the laboratory that analyzes the test.

Interpreting AST Test Results

What does a high AST test result indicate?

A high AST level could indicate liver damage, heart damage, or damage to other tissues where AST is found. It's usually not possible to determine the source of the damage based solely on the AST test.

Can you interpret the AST test result in isolation?

No, the AST test is often interpreted in conjunction with other tests, like the ALT (Alanine Aminotransferase) test, to get a more accurate picture of an individual's health.

AST Test and Specific Conditions

How is the AST test used in diagnosing and managing liver diseases?

In liver diseases like hepatitis or cirrhosis, AST levels often increase. The AST test can help diagnose these conditions and monitor the effectiveness of treatment.

Why is the AST test important in assessing heart damage, such as from a heart attack?

While less common today, the AST test was traditionally used to help diagnose heart attacks. An increase in AST levels can indicate heart muscle damage.

How does the AST test assist in diagnosing muscle disorders?

Elevated AST levels can be seen in conditions causing muscle damage, such as muscular dystrophy or after intense exercise. The AST test can help in diagnosing these conditions.

Can the AST test assist in the diagnosis of pancreatitis?

Yes, in acute pancreatitis, both AST and ALT levels can increase, so the AST test can help in diagnosis.

General Questions about the AST Test

Can certain medications affect the AST test result?

Yes, certain medications can cause a rise in AST levels, including statins, antibiotics, and anti-seizure medications.

Can the AST test be performed more than once?

Yes, the AST test can be repeated to monitor the progression of a disease or the effectiveness of treatment.

Can the AST test help detect chronic alcohol abuse?

Chronic alcohol use can cause liver damage, which can raise AST levels. The AST test, along with other tests, can help detect this.

Can the AST test help in monitoring the progression of liver fibrosis and cirrhosis?

Yes, increased AST levels can reflect ongoing damage to the liver, such as with fibrosis or cirrhosis, and can help monitor disease progression.

What is the AST/ALT ratio and how is it used?

The AST/ALT ratio compares the levels of AST and ALT in the blood. An AST/ALT ratio greater than 2 is often seen in alcoholic liver disease.

How does the AST test help in understanding the cause of symptoms like jaundice, dark urine, or abdominal pain?

These symptoms can be caused by liver disease. As AST is often elevated in liver disease, the AST test can help determine if liver disease is the cause.

What role does the AST test play in the diagnosis and management of autoimmune hepatitis?

In autoimmune hepatitis, the immune system attacks liver cells, leading to elevated AST levels. The AST test can help diagnose this condition and monitor treatment response.

How does the AST test assist in diagnosing viral hepatitis infections like Hepatitis B or C?

In viral hepatitis, the liver is inflamed, often leading to elevated AST levels. The AST test can assist in diagnosing these conditions.

Can the AST test help identify liver damage due to exposure to toxins or drugs?

Yes, exposure to toxins or certain drugs can cause liver damage, which can raise AST levels. The AST test can help identify this damage.

Can the AST test help in the diagnosis of hemochromatosis?

In hemochromatosis, iron builds up in the body and can damage the liver, leading to increased AST levels. The AST test can assist in diagnosing this condition.

How does the AST test assist in the diagnosis of non-alcoholic fatty liver disease (NAFLD)?

In NAFLD, fat builds up in the liver, which can cause damage and raise AST levels. The AST test can assist in diagnosing this condition.

What is the role of the AST test in monitoring the effectiveness of treatments for liver disease?

Treatments for liver disease aim to reduce liver damage. A decrease in AST levels can indicate that treatment is working.

Can the AST test be used to detect liver damage in people with diabetes?

Yes, people with diabetes can develop a condition called diabetic hepatopathy, where the liver is damaged. The AST test can help detect this.

How does the AST test assist in the diagnosis of gallbladder disease?

While the AST test is not specific to gallbladder disease, AST levels can increase if the liver is damaged due to a blocked bile duct, a potential complication of gallbladder disease.

Can the AST test help determine the severity of liver damage in hepatitis C patients?

While the AST test can show the presence of liver damage in hepatitis C patients, additional tests are usually needed to determine the extent of the damage.

Can the AST test assist in assessing the liver's response to therapeutic interventions in conditions like hepatitis B?

Yes, decreased AST levels after therapeutic interventions can indicate a positive response to treatment in conditions like hepatitis B.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.