Impaired oxidation of carbon-labeled galactose by alcoholic or diabetic liver in vivo.

Because of the organ and enzyme specificity of the metabolism of galactose, evaluation of various kinds of liver disease can be done by measuring the formation of labeled breath CO2 from carbon-labeled galactose in vivo. As shown earlier with uniformly 14C- or 13C-labeled galactose, a further study of alcoholic cirrhotic patients and controls with cheaper 1-14C-galactose indicates a superior discriminatory value of this test compared with common liver function tests. The oxidation test is easier to perform and more acceptable to patients than the standard galactose tolerance blood test. Output of 14CO2 showed slight correlations with serum albumin and 99mTc-sulfur colloid scan grade, but not with other function tests (SGOT, alkaline phosphatase, bilirubin). Comparison with five-year clinical outcome (two groups: with or without known liver-related death) in 29 of 43 total cirrhotic patients (U-14C or 1-14C-galactose) showed a low (75% probability) significance of prognosis for the galactose oxidation test, but none for any of the other tests. A two-part test of oxidation of 14C-galactose (with and without an acute dose of ethanol) in 19 possibly or likely alcoholic (but non-cirrhotic) persons indicated, by correlation with other liver function tests and drinking history, some possibly enhanced sensitivity of the two-part versus the single test for recognizing early liver damage. A preliminary study of the single galactose oxidation test in 7 patients with Type II diabetes suggests moderate impairment of oxidation, which might be applied to evaluate the hepatic disorder in diabetes.