Human serum alcohol dehydrogenase isoenzymes as a markers of liver injury during viral hepatitis.
We examined the activity of class I and II of alcohol dehydrogenase isoenzymes in the sera of patients with viral hepatitis using fluorogenic substrates, 4-methoxy-1-naphthaldehyde for class I and 6-methoxy-2-naphthaldehyde for class II. It was found that serum activities of class I and II of alcohol dehydrogenase isoenzymes during five weeks of hospitalisation were higher than that of control. The greatest increase in activities was found at the onset of disease, and exceeded the mean control value about 30 times for class I and 4 times for class II. These were lower than the aminotransferase activities but higher than the activity of lactate dehydrogenase, alkaline phosphatase and gamma-glutamyltransferase. In the following periods of investigation the activity of alcohol dehydrogenase isoenzymes gradually decreased, but did not reach the values of the control groups in the last period of the study. Activity of class I and II of alcohol dehydrogenase isoenzymes showed a good correlation with alanine and aspartate aminotransferase and lactate dehydrogenase in the first weeks of the illness. These results clearly demonstrate that particularly the activity of class I of alcohol dehydrogenase isoenzymes measured by a fluorimetric method can be a useful marker of liver cell damage in the course of viral hepatitis.