The Gamma Glutamyl Transferase (GGT) test contains 1 test with 1 biomarker.
Brief Description: The Gamma Glutamyl Transferase (GGT) test measures the levels of the enzyme gamma glutamyl transferase in the blood. GGT is primarily found in the liver, bile ducts, and kidneys. The GGT test helps assess liver function and is used to diagnose and monitor liver diseases and conditions that affect the biliary system.
Also Known As: Gamma Glutamyltransferase GGT test, Gamma-Glutamyl Transferase Test, Gamma-Glutamyl Transpeptidase Test, Gamma-GT Test, GGTP Test, GTP Test
Collection Method: Blood Draw
Specimen Type: Serum
Test Preparation: No preparation required
When is a GGT test ordered?
A Gamma Glutamyl Transferase test may be ordered in several situations to assess GGT levels:
Evaluation of Liver Function: The GGT test is commonly ordered as part of a liver function panel to evaluate liver health and function. It provides specific information about liver enzymes and aids in diagnosing liver diseases.
Assessment of Alcohol Abuse: GGT levels are often elevated in individuals who abuse alcohol. The test helps evaluate the impact of alcohol on the liver and assess alcohol-related liver damage.
Screening for Liver Diseases: The GGT test may be used as a screening tool to detect liver diseases, especially in individuals with risk factors such as alcohol abuse, obesity, viral hepatitis, or medication use known to affect the liver.
Monitoring Liver Disease Progression: In individuals diagnosed with liver diseases such as hepatitis, cirrhosis, or fatty liver disease, the GGT test helps monitor disease progression, evaluate treatment effectiveness, and assess liver function over time.
What does a GGT blood test check for?
Glutamyl transferase is an enzyme found throughout the body, with the liver having the highest amount of it. GGT levels in the blood are raised in most disorders that affect the liver or bile ducts. This test determines the amount of GGT present in a blood sample.
GGT is normally present in tiny amounts, however when the liver is harmed, the level of GGT might grow. When any of the bile ducts that convey bile from the liver to the intestines become clogged, GGT levels are usually the first liver enzyme to become elevated in the blood. It's the most sensitive liver enzyme test for diagnosing bile duct issues because of this.
However, because it can be raised with many types of liver disorders, the GGT test is not highly specific and is not effective in differentiating between various causes of liver damage. As a result, the GGT test is not suggested for usage on a regular basis. It can, however, be used in conjunction with other tests to determine the source of a high alkaline phosphatase level, which is another liver enzyme.
In liver disorders, both GGT and ALP are elevated, whereas only ALP is elevated in diseases that impact bone tissue. As a result, GGT can be used as a follow-up test to establish whether an elevated ALP result is related to liver or bone illness.
When even small amounts of alcohol are consumed, GGT levels can sometimes rise. Chronic heavy drinkers have higher levels than persons who drink less than 2 to 3 drinks per day or who only drink heavily on rare occasions. The GGT test can be used to determine whether someone is suffering from acute or chronic alcoholism.
Lab tests often ordered with a GGT test:
When a GGT test is ordered, it may be accompanied by the following tests to give a more comprehensive overview of liver function and to help distinguish between liver and bone disease:
Alkaline Phosphatase (ALP):
- Purpose: To measure the level of ALP, an enzyme related to the biliary tract that can be elevated in liver disease.
- Why Is It Ordered: If ALP is elevated, measuring GGT can help confirm whether the high ALP is from liver origin, since ALP can also come from bone.
Alanine Aminotransferase (ALT):
- Purpose: To assess liver function by measuring the level of ALT, an enzyme found primarily in the liver.
- Why Is It Ordered: ALT is more specific for liver cell damage than GGT and is often used to evaluate and monitor the extent of liver injury.
Aspartate Aminotransferase (AST):
- Purpose: To measure the level of AST, an enzyme found in high amounts in the liver, heart, and other muscles.
- Why Is It Ordered: AST, in conjunction with ALT, helps evaluate liver health. An AST/ALT ratio can also give clues about the cause of liver damage.
- Purpose: To measure the amount of bilirubin in the blood, which is produced during the normal breakdown of red blood cells.
- Why Is It Ordered: Bilirubin levels can indicate how well the liver clears bilirubin, which can be affected in various liver and bile duct disorders.
Albumin and Total Protein:
- Purpose: To assess liver function by measuring the main protein made by the liver (albumin) and the total amount of serum protein.
- Why Is It Ordered: Low levels of albumin and changes in the total protein level can indicate chronic liver disease.
Liver Function Tests (LFTs):
- Purpose: To give a broader picture of liver health.
- Why Is It Ordered: LFTs typically include ALP, ALT, AST, GGT, bilirubin, albumin, and total protein. They are used together to assess liver injury or disease.
- Purpose: To determine the presence of viral hepatitis, such as hepatitis A, B, or C.
- Why Is It Ordered: Viral hepatitis is a common cause of liver enzyme elevation and liver disease.
Prothrombin Time (PT):
- Purpose: To measure the blood’s ability to clot, which requires clotting factors produced by the liver.
- Why Is It Ordered: An extended PT can indicate liver damage or disease affecting the production of clotting factors.
Lactate Dehydrogenase (LDH):
- Purpose: To measure the level of LDH, an enzyme that is elevated with tissue damage.
- Why Is It Ordered: Although not liver-specific, it can be ordered to assess overall tissue damage and sometimes to differentiate between different types of liver disease.
The combination of these tests, along with the clinical history and physical examination, helps healthcare providers diagnose the cause of liver dysfunction, monitor the progression of liver disease, and guide treatment decisions.
Conditions where a GGT test is recommended:
A Gamma Glutamyl Transferase test is commonly ordered for:
Liver Diseases: The test helps diagnose and monitor various liver diseases, including hepatitis, cirrhosis, fatty liver disease, and drug-induced liver injury.
Alcohol Abuse: Individuals who abuse alcohol often exhibit elevated GGT levels, making the test valuable in assessing alcohol-related liver damage.
Biliary System Disorders: Conditions affecting the biliary system, such as gallstones, cholestasis, or biliary obstruction, may lead to elevated GGT levels.
Medication-induced Liver Injury: Certain medications or toxins can affect liver function and cause elevated GGT levels.
How does my healthcare provider use a GGT test?
Healthcare providers use the results of a Gamma Glutamyl Transferase test to:
Assess Liver Function: GGT levels, along with other liver enzymes, help healthcare providers evaluate liver function and identify liver diseases or conditions affecting liver health.
Diagnose Liver Diseases: Abnormal GGT levels aid in diagnosing liver diseases such as hepatitis, cirrhosis, or fatty liver disease.
Evaluate Alcohol-Related Liver Damage: Elevated GGT levels in individuals with alcohol abuse or alcohol-related liver disease assist healthcare providers in assessing the extent of liver damage caused by alcohol.
Monitor Disease Progression: The GGT test helps healthcare providers monitor the progression of liver diseases, evaluate treatment effectiveness, and assess liver function over time.
By effectively utilizing the results of a Gamma Glutamyl Transferase test, healthcare providers can assess liver function, diagnose liver diseases, evaluate alcohol-related liver damage, monitor disease progression, and make informed decisions regarding patient care and treatment interventions related to liver health.
What do my GGT test results mean?
An high GGT level indicates that the liver is being harmed by a condition or disease, but it does not specify what that ailment or disease is. In general, the higher the level, the worse the liver damage. Elevated levels can be caused by liver illnesses like cirrhosis or hepatitis, but they can also be caused by other conditions like congestive heart failure, diabetes, or pancreatitis. They can also be caused by alcohol misuse or the use of liver-toxic medications.
A GGT test result that is low or normal suggests that a person does not have liver disease or has not recently consumed alcohol.
A high GGT level can help rule out bone disease as the source of an elevated ALP level, but if GGT is low or normal, bone disease is the most likely explanation.
Most Common Questions About the Gamma Glutamyl Transferase test:
Test Purpose and Basics
What does the Gamma Glutamyl Transferase test measure?
The GGT test measures the level of gamma-glutamyl transferase, an enzyme found mainly in the liver. High levels of GGT in the blood can indicate liver disease or bile duct obstruction.
What conditions could lead to a doctor ordering a Gamma Glutamyl Transferase test?
A GGT test might be ordered if a patient has symptoms suggestive of liver disease, such as jaundice, dark urine, nausea, vomiting, or abdominal pain. It's also often used to determine if high levels of alkaline phosphatase are due to liver disease or bone disease.
How does the Gamma Glutamyl Transferase test relate to other liver function tests?
The GGT test is one of several tests that assess liver function. Others include tests for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin, and albumin. Together, these tests give a more complete picture of liver health.
Test Results Interpretation
What does a high Gamma Glutamyl Transferase test result indicate?
High GGT levels may indicate liver disease, alcohol abuse, or an obstruction in the bile ducts. However, other tests are usually needed to confirm a diagnosis and determine the specific cause.
What does a low Gamma Glutamyl Transferase test result indicate?
Low GGT levels are typically not a cause for concern and do not usually indicate a specific condition.
Can medication influence the Gamma Glutamyl Transferase test results?
Yes, certain medications, such as phenytoin and barbiturates, can increase GGT levels, while aspirin and clofibrate can decrease GGT levels. Alcohol consumption can also raise GGT levels.
Are there age or gender differences in the Gamma Glutamyl Transferase test results?
GGT levels tend to increase with age. Men also generally have higher GGT levels than women.
How can the Gamma Glutamyl Transferase test help in diagnosing alcohol abuse?
Chronic alcohol consumption can lead to elevated GGT levels. Therefore, if a patient has a high GGT level and there's no other apparent cause, it might suggest alcohol abuse.
Is the Gamma Glutamyl Transferase test used in the management of known liver disease?
Yes, the GGT test can be used to monitor the progression of liver disease and the effectiveness of treatment.
Can the Gamma Glutamyl Transferase test be used to predict cardiovascular risk?
Some studies suggest that high GGT levels might be associated with an increased risk of cardiovascular disease. However, the GGT test is not typically used alone for this purpose.
How often should the Gamma Glutamyl Transferase test be repeated in patients with liver disease?
The frequency of testing depends on the specific condition, its severity, and the treatment plan. It's a question best answered by the treating physician.
Can the Gamma Glutamyl Transferase test be used to assess liver damage in patients with hepatitis C?
The GGT test can help assess liver damage in various forms of liver disease, including hepatitis C. However, other tests are also typically used for a more complete assessment.
Does the Gamma Glutamyl Transferase test help in diagnosing gallstones?
Elevated GGT levels can indicate a blockage in the bile ducts, which might be caused by gallstones. However, other diagnostic tests like ultrasound are more directly used to diagnose gallstones.
Is the Gamma Glutamyl Transferase test useful in diagnosing liver cancer?
While elevated GGT levels can be seen in liver cancer, the test is not specific for this condition. Other diagnostic tools, like imaging and biopsy, are necessary to diagnose liver cancer.
Can lifestyle modifications affect the results of the Gamma Glutamyl Transferase test?
Yes, alcohol cessation and adopting a healthy lifestyle can help lower elevated GGT levels associated with alcohol abuse or liver disease.
What other tests might be done alongside the Gamma Glutamyl Transferase test?
Typically, the GGT test is done as part of a liver panel, which might also include tests for ALT, AST, ALP, bilirubin, and albumin.
Does the Gamma Glutamyl Transferase test help in monitoring patients on certain medications?
Certain medications can harm the liver. If a patient is on such a drug, a physician might use the GGT test to monitor for potential drug-induced liver injury.
Can the Gamma Glutamyl Transferase test be used to differentiate between bone disease and liver disease?
Yes, if ALP levels are elevated, a GGT test can help determine whether the increase is due to bone disease or liver disease. GGT levels are usually normal in bone disease.
How are the results of the Gamma Glutamyl Transferase test presented?
GGT results are typically presented as units per liter (U/L). The normal range can vary depending on the patient's gender and age, but it is generally around 3-70 U/L.
Can the Gamma Glutamyl Transferase test results change during pregnancy?
Yes, GGT levels can be slightly elevated during pregnancy, but they are typically not as high as in conditions like liver disease or bile duct obstruction.
Does obesity affect the results of the Gamma Glutamyl Transferase test?
Yes, obesity is associated with non-alcoholic fatty liver disease (NAFLD), which can lead to elevated GGT levels.
How does diabetes impact the results of the Gamma Glutamyl Transferase test?
Elevated GGT levels are associated with insulin resistance and type 2 diabetes. Therefore, a patient with diabetes might have higher GGT levels.
What can cause false positives or negatives in the Gamma Glutamyl Transferase test?
Certain medications can raise or lower GGT levels, potentially leading to false positives or negatives. Dehydration might also affect test results.
Is the Gamma Glutamyl Transferase test used in pediatric cases?
Yes, the GGT test can be used in children if there's a suspicion of liver disease or bile duct obstruction.
Can the Gamma Glutamyl Transferase test be used in the evaluation of unexplained weight loss?
While unexplained weight loss can sometimes be a sign of liver disease, the GGT test is not typically used on its own for this purpose. However, it might be included as part of a broader diagnostic workup.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.