Transport of serum bile acids in patients with liver cirrhosis and hyperbilirubinaemia

From 12 patients with liver cirrhosis and hyperbilirubinaemia, the different conjugates of bilirubin and bile acids in the serum were separated and determined. The serum of the patients contained varying amounts of unconjugated bilirubin, which was not correlated to total serum bilirubin. No correlation between bilirubin conjugates and different conjugates of bile acids could be found, indicating different elimination processes for these substances. To examine whether a changed plasma transport of bile acids, which may contribute to the different excretion pattern of bilirubin and bile acids, occurs in liver cirrhosis, the bile acids in the different serum lipoprotein fractions were determined in seven of the patients. It was found that 40% of serum bile acids were bound to serum lipoproteins, despite decreased serum lipoprotein levels. The degree of lipoprotein binding of bile acids was not correlated to total serum bile acid concentrations. Cholic acid conjugates were present to a higher extent in the lipoprotein fractions than those of chenodeoxycholic acid or of deoxycholic acid. Determination was made of the distribution of individual conjugates between different lipoproteins and it was found that most of the glycine conjugates were present in high density lipoprotein, whereas the main part of sulphates and taurine conjugates were present in low density lipoprotein. These results indicate that a higher fraction of bile acids in liver cirrhosis is transported by lipoproteins in plasma, which may be of importance for the hepatic elimination of bile acids in cases with this disease.