1. Hepatitis Slideshow Pictures
2. Take the Alcohol Quiz
3. Alcohol Abuse Slideshow Pictures

Medical Author:

Siamak T. Nabili, MD, MPH

Siamak T. Nabili, MD, MPH

Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• What are the basic functions of the liver?
• What are common liver blood tests?
• What are the aminotransferases?
• Normally, where are the aminotransferases?
• What are normal levels of AST and ALT?
• What do elevated liver tests (AST and ALT) mean?
• Does AST and ALT measurements indicate liver function?
• Which blood tests are done to detect liver function?
• What are some common reasons for abnormal liver tests?
• What medications can cause abnormal aminotransferase levels?
• What conditions can cause very high aminotransferase levels?
• What are some of the less common causes of elevated liver blood tests?
• How are healthy people evaluated for mild to moderate rises in aminotransferase levels?
• How about monitoring liver blood tests?
• What about the other liver enzymes?
• Hepatitis Slideshow Pictures
• Take the Alcohol Quiz
• Alcohol Abuse Slideshow Pictures
• Patient Comments: Liver Blood Tests - Diagnosis
• Patient Comments: Liver Blood Tests - Why
• Patient Comments: Liver Blood Tests - Test
• Liver Blood Tests Index

How about monitoring liver blood tests?

What is usually most helpful is serial testing of AST (SGOT) and ALT (SGPT) over time to determine whether the levels are increasing, remaining stable, or decreasing. For example, individuals undergoing treatment for chronic hepatitis C should be monitored with serial liver enzyme tests. Those responding to treatment will experience lowering of liver enzyme levels to normal or near normal levels. Those who develop relapse of hepatitis C after completion of treatment will usually develop abnormal liver enzyme levels again.

What about the other liver enzymes?

Aside from AST and ALT, there are other enzymes including alkaline phosphatase, 5'-nucleotidase ("5 prime" nucleotidase), lactate dehydrogenase (LDH), and gamma-glutamyl transpeptidase (GGT) that are often used to detect for liver disease.

LDH is not specific to the liver and can be elevated in many diseases with inflammation in other tissues.

Alkaline phosphatase is a liver enzyme that is frequently measured. This enzyme is usually found in the walls of the bile ducts (tube-like structures within the liver that connect liver cells together). Elevation of alkaline phosphatase may indicate an injury to the biliary cells. Common causes of biliary injury or biliary obstruction (cholestasis) are gallstones and certain mediations, although, some of the conditions listed previously can also raise the levels of this enzyme. Alkaline phosphate is also found in the bone and can be elevated in bone diseases. GGT and 5' nucleotidase levels can be elevated in biliary conditions (disease of the gallbladder and bile ducts) along with alkaline phosphatase.

REFERENCES:

Fauci, Anthony S., et al. Harrison's Principles of Internal Medicine. 17th ed. United States: McGraw-Hill Professional, 2008.

WebMD.com. Liver Tests.