Evaluation of postprandial serum bile acid response as a test of hepatic function

Commercial assays for serum bile acids (SBA) have made this measurement practical. The purpose of this study was to examine the utility of SBA measured every 30 min after a standardized meal in controls and in patients with acute viral hepatitis, cholestasis, and anicteric cirrhosis. In five controls, repeated examination of the area under the bile acid curve (AUC) was not statistically different, whereas the fasting and 2-hr postprandial levels were significantly different. In the group of patients with anicteric cirrhosis, AUC identified disease in 18/20 using total serum bile acids (TSBAs) and in 15/20 using cholylglycine (CG). AUC can be calculated from three samples obtained at 0, 60, and 120 min without losing the sensitivity achieved with seven serial samples. SGOT, alkaline phosphatase, and serum albumin were compared for sensitivity to the total SBA response curve in 20 patients with anicteric cirrhosis. SGOT and alkaline phosphatase identified only 50% and 55% as abnormal and serum albumin was less sensitive. Using total SBA, combining the fasting level and AUC identified 100% as abnormal; using CG, 85% of these patients were detected. As a stepwise cost-effective approach, the fasting level of SBAs can identify most patients with anicteric liver disease. In cases with normal fasting levels where liver disease is suspected, the three-point AUC determination may identify additional patients.