Serum guanase activity was measured in 20 healthy adults and in 62 patients with
acute viral hepatitis, chronic active hepatitis, chronic persistent hepatitis, liver cirrhosis and fatty
liver. Guanase and γ-GT in patients were elevated in 87 and 64%, respectively. Elevated guanase
activities were found in most cases of acute viral hepatitis, as well as in chronic hepatopathies. In
patients with acute viral hepatitis pathologic activities of guanase were found following partial or
total normalization of other liver function tests.