The diagnostic value of the ratio of serum gamma-glutamyl transpeptidase to alkaline phosphatase in alcoholic liver disease.

A prospective study of the initial liver laboratory tests was carried out in the following patients: 55 patients with alcoholic liver disease, 53 with cholangitis, 41 with hepatocellular carcinoma, 65 with acute viral hepatitis, and 49 with hepatitis-B surface antigen-positive chronic active hepatitis. There was considerable overlap in the levels of the serum gamma-glutamyl transpeptidase (GT) and alkaline phosphatase (AP) among the five groups. However, the ratio of GT to AP was significantly higher in the group with alcoholic liver disease than in any of the other four groups. When the ratio was higher than 1.4, the diagnostic efficiency for distinguishing the alcohol group from the other four groups was 78% (the normal upper limit for GT and AP being 35 and 115 U/1, respectively). A possible explanation for this higher ratio in alcoholic liver disease is suggested. We conclude that when the GT and AP is greater than 1.4, it is of greater diagnostic value than either variable alone in differentiating alcoholic from other liver diseases.