Diagnostic value of serum cholylglycine radioimmunoassay in chronic asymptomatic HBsAg carriers.

The correlation between histological liver abnormalities and fasting serum cholylglycine levels was investigated in 75 chronic asymptomatic HBsAg carriers with normal conventional liver tests, to clarify whether serum CG radioimmunoassay could help in distinguishing the carriers with histological liver damage from those with normal histological findings. Mean (+/- SEM) fasting serum CG levels were 11.6 +/- 1.5 micrograms/dl in 56 carriers with normal liver histology, 14.6 +/- 4.2 micrograms/dl in 16 subjects with CPH and 95.6 +/- 54 micrograms/dl in three carriers with CAH. The incidence of abnormal values (greater than 40 micrograms/dl) among carriers with CAH (66%) was significantly higher than in the other two groups (1.8 and 12.5%, respectively). It is concluded that, among chronic asymptomatic HBsAg carriers with normal conventional liver tests, those who show abnormal serum CG levels are likely to have severe histological damage. This justifies the inclusion of CG radioimmunoassay in the routine follow-up of these subjects. The occurrence of false-positive and false-negative results must be considered if the test is used as an aid in the selection of patients for liver biopsy.