Determination of bile acid levels in the serum in the presence of various hepatobiliary disorders using two different radioimmunoassays

240 patients were assigned to 15 study groups according to the individual hepatobiliary diseases diagnosed; their GC and SLCG bile acid concentrations (cholylglycine and sulfolithocholylglycine) were determined against twenty control sera with the aid of two commercially available radioimmunoassays using iodine 125 and the results thus obtained compared with 18 parameters from among the range of clinico-chemical routine examinations. The test results were observed to vary according to incubations times and temperatures, serum volumes used and added amounts of tracer substance. Both test systems were easy to handle and showed acceptable intra-assay and inter-assay variations. The mean values of all the determinations carried out in the individual study groups showed significant increases, even though no convincing correlations were seen between these and the remaining clinico-chemical parameters mentioned above. The sensitivity of SLCG was inferior to that of CG throughout, while the sensitivity of the laboratory parameters showed a progressive decline, beginning from the study groups with acute liver damage down to hepatobiliary diseases of a chronic nature. It is of particular note that in the study groups of patients with inactive cirrhosis and chronic aggressive hepatitis the majority of parameters failed to give evidence of pathological changes, while the GC and SLGC values were characterised by increases. Determinations of the CG and SLGC serum levels may thus throw some light on cases where hepatobiliary affections are suspected and the usual cinico-chemical test batteries have provided only little information to confirm the diagnosis. (TRV)