Serum bile acids and alanine aminotransferase concentrations. Comparison of efficacy as indirect means of identifying carriers of non-A, non-B hepatitis agents and of onset, severity, and duration of posttransfusion non-A, non-B hepatitis in recipients.

Indirect tests of liver function such as determinations of concentrations of alanine aminotransferase (ALT) and conjugated bile acids (BA) have been advocated as indicators of both the infectivity of the blood of donors in transmitting non-A, non-B (NANB) hepatitis and of the onset, severity, and duration of this disease in recipients. We therefore compared the predictive value of concentrations of ALT and postprandial concentrations of BA in the blood of 311 donors and in the blood of 41 recipients in whom either NANB or type B hepatitis developed after transfusion. Our results demonstrated that higher than normal concentrations of ALT (greater than 45 IU/L) in the blood of donors were generally accompanied with normal concentrations of BA (less than 6 mumole/L), and, therefore, concentrations of ALT may be more useful in predicting the infectivity of donor blood in transmitting NANB hepatitis. In addition, concentrations of ALT, compared with BA concentrations, were a significantly better indicator of the onset, severity, and duration of the disease in recipients in whom NANB hepatitis developed after transfusion. In recipients who had posttransfusion type B hepatitis, serum concentrations of ALT were significantly better indicators of the onset and severity of the disease than concentrations of BA.