Bile Acids, Fractionated and Total, Serum
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Bile acids are formed in the liver from cholesterol, conjugated primarily to glycine and taurine, stored and concentrated in the gallbladder, and secreted into the intestine after the ingestion of a meal. In the intestinal lumen, the bile acids serve to emulsify ingested fats and thereby promote digestion. During the absorptive phase of digestion, approximately 90% of the bile acids are reabsorbed.
The efficiency of the hepatic clearance of bile acids from portal blood maintains serum concentrations at low levels in normal persons. An elevated fasting level, due to impaired hepatic clearance, is a sensitive indicator of liver disease. Following meals, serum bile acid levels have been shown to increase only slightly in normal persons, but markedly in patients with various liver diseases, including cirrhosis, hepatitis, cholestasis, portal-vein thrombosis, Budd-Chiari syndrome, cholangitis, Wilson disease, and hemochromatosis. No increase in bile acids will be noted in patients with intestinal malabsorption. Metabolic hepatic disorders involving organic anions (eg, Gilbert disease, Crigler-Najjar syndrome, and Dubin-Johnson syndrome) do not cause abnormal serum bile acid concentrations.
Measurement of tauro- and glycol-conjugated and unconjugated bile acid constituents in serum
Monitoring patients receiving bile acid therapy, such as cholic acid, deoxycholic acid, or ursodeoxycholic acid
Aiding in the evaluation of liver function; evaluation of liver function changes before the formation of more advanced clinical signs of illness such as icterus
Determining hepatic dysfunction as a result of chemical and environmental injury
Indication of hepatic histological improvement in chronic hepatitis C patients responding to interferon treatment
Indication of intrahepatic cholestasis of pregnancy
Total bile acids are metabolized in the liver and can serve as a marker for normal liver function. Increases in serum bile acids are seen in patients with acute hepatitis, chronic hepatitis, liver sclerosis, liver cancer, and intrahepatic cholestasis of pregnancy.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
This test does not measure sulfated bile acids.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Total Cholic Acid
< or =5.00
Total Chenodeoxycholic Acid
< or =6.00
Total Deoxycholic Acid
< or =6.00
Total Ursodeoxycholic Acid
< or =2.00
Total Bile Acids
< or =19.00
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Tribe RM, Dann AT, Kenyon AP, et al: Longitudinal profiles of 15 serum bile acids in patients with intrahepatic cholestasis of pregnancy. Am J Gastroenterol 2010 Mar;105(3):585-595
2. Marschall HU: Management of intrahepatic cholestasis of pregnancy. Expert Rev Gastroenterol Hepatol 2015 Oct;9(10):1273-1279
3. Ducroq DH, Morton MS, Shadi N, et al: Analysis of serum bile acids by isotope dilution-mass spectrometry to assess the performance of routine total bile acid methods. Ann Clin Biochem 2010 Nov;47(Pt 6):535-540