Bile Acids

Bile Acids

Number
	010330
CPT
	82239
Synonyms
	Glyco and Taurochenodeoxycholic Acid ; Glyco and Taurocholic Acid
Specimen
	Serum, frozen
Volume
	1 mL
Minimum Volume
	0.2 mL
Container
	Red-top tube or gel-barrier tube
Collection
	Transfer serum to a plastic transport tube before freezing. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Storage Instructions
	Freeze Note: Bile acids are unstable when subjected to freezing, thawing, and re-freezing, therefore, avoid freeze/thaw cycles.
Patient Preparation
	Patient should be fasting; however, a 2-hour postprandial level has been used by various physicians in order to evaluate hepatic function after the gallbladder has been completely emptied (ie, challenge the liver with a high level of bile acids in the portal circulation).
Causes for Rejection
	Specimen not frozen; use of anticoagulants; re-frozen specimen
Reference Interval
	4.5-24.6 μmol/L
Use
	Evaluate the enterohepatic cycle consisting of the biliary system, intestine, portal circulation, and hepatocytes
Methodology
	Enzymatic
Additional Information
	The concentration of bile acids in serum is elevated in patients with many structural liver diseases, due to the inability of the liver to extract bile acids efficiently from portal blood. Metabolic liver diseases such as Gilbert disease, Crigler-Najjar syndrome, or Dubin-Johnson syndrome do not appear to cause elevated bile acid concentrations. Bile acid levels may be altered even when other liver function tests are normal and may serve as a sensitive and specific indicator of liver disease.
References
	Block E, et al, “Efficacy of Postprandial Bile Acid Levels as Diagnostic Tool for Hepatobiliary Disease,” Clin Chem, 1979, 25:1081. Korman MG, Hofmann AF, Summerskill WH, et al, “Assessment of Activity in Chronic Liver Disease: Serum Bile Acids Compared With Conventional Tests and Histology,” N Engl J Med, 1974, 290(25):1399-402. Mashige F, Tanaka N, Maki A, et al, “Direct Spectrophotometry of Total Bile Acids in Serum,” Clin Chem, 1981, 27(8):1352-6. Skrede E, Solberg HE, Blomhoff JP, et al, “Bile Acids Measured in Serum During Fasting as a Test for Liver Disease,” Clin Chem, 1978, 24(7):1095-9.