Differential diagnostic value in hepatobiliary disease of serum conjugated bile acid concentrations and some routine liver tests assessed by discriminant analysis.

Serum concentrations of glycine and taurine conjugates of cholic, chenodeoxycholic, and deoxycholic acid were measured with a HPLC-enzymatic assay in 104 patients with hepatobiliary diseases. The capability of discriminating between four major diagnostic categories by the serum bile acid concentrations, alone and in conjunction with five commonly used biochemical liver tests, was evaluated by stepwise linear discriminant analysis. The serum bile acid pattern alone was inferior to the routine liver tests in separating the diagnostic groups. When the two sets of analytes were combined, the generalized group distance (Rao's V) was significantly increased, showing that the serum bile acid pattern contained discriminatory information in addition to the routine liver tests. The gain in correct reclassification of patients obtained by adding the serum bile acids, however, was only marginal.