Plasma disappearance of 14C-glycocholic acid as a test of liver dysfunction. Relation to liver histology.

The present study was undertaken to evaluate the clinical usefulness of determining the plasma disappearance of 14C-glycocholic acid in the diagnosis of hepatic disease. This test was compared with the sulfobromophthalein test in 8 control subjects and 46 patients with abnormal liver histology (15 with fatty liver, 20 with alcoholic liver cirrhosis, 6 with primary biliary cirrhosis, and 5 with chronic hepatitis). The best distinction between controls and patients with liver disease was obtained by using the ratio between the plasma radioactivities at 45 and 2 min. However, even then, the 14C-glycocholic acid test had a very low sensitivity for the four groups of patients (0, 60, 50, and 40%, respectively) compared with the sulfobromophthalein test (73%, 90%, 67%, and 100% respectively). The lower sensitivity of the 14C-glycocholic acid test may be explained by the assumption that the clearance of a radioactive tracer dose is more dependent on liver blood flow than on liver function. This test is thus of little clinical value in separating patients with and without normal hepatic histology.