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The Asymptomatic Patient With Abnormal Liver Test Results


Danielle Tholey

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Sep 2023

Because aminotransferases and alkaline phosphatase are included in commonly done laboratory test panels, abnormalities are often detected in patients without symptoms or signs of liver disease. In such patients, the physician should obtain a history of exposure to possible liver toxins, including alcohol, prescription and nonprescription drugs, herbal teas and botanical remedies, and occupational or other chemical exposures.


Mild isolated elevations of alanine aminotransferase (ALT) or aspartate aminotransferase (AST; < 2 times normal) may require only repeat testing; they resolve in about one third of cases. It is important to clarify if laboratory tests were done in the fasting state because oral intake can cause mild elevations in tests of liver function. If abnormalities are present in other laboratory tests, are severe, or persist on subsequent testing, further evaluation is indicated as follows:

Alkaline phosphatase

Isolated elevation of alkaline phosphatase levels in an asymptomatic patient requires confirmation of hepatic origin by showing elevation of 5´-nucleotidase or gamma-glutamyl transpeptidase. If hepatic origin is confirmed, liver imaging Imaging Tests of the Liver and Gallbladder Imaging is essential for accurately diagnosing biliary tract disorders and is important for detecting focal liver lesions (eg, abscess, tumor). It is limited in detecting and diagnosing diffuse... read more Imaging Tests of the Liver and Gallbladder , usually with ultrasonography or magnetic resonance cholangiopancreatography, is indicated.

If no structural abnormality is found on imaging, intrahepatic cholestasis is possible and may be suggested by a history of exposure to drugs or toxins. Infiltrative diseases and liver metastases (eg, due to colon cancer) should also be considered. In women, antimitochondrial antibody should be obtained to check for primary biliary cholangitis Primary Biliary Cholangitis (PBC) Primary biliary cholangitis (PBC; formerly known as primary biliary cirrhosis) is an autoimmune liver disorder characterized by the progressive destruction of intrahepatic bile ducts, leading... read more . Persistent unexplained elevations or suspicion of intrahepatic cholestasis warrants consideration of liver biopsy.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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