Abstract: Objective　To investigate the prognostic significance of the serum aspartate aminotransferase mitochondrial isoenzyme (m-AST) activity in alcoholic liver disease (ALD).  Methods　The serum levels of m-AST，gamma-glutamyltransferase (GGT)，alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined by immuno-inhibition assays in 104 patients with ALD [ALD group，including alcoholic fatty liver (AFL) 36 cases，alcoholic hepatitis (AH) 52 cases and alcoholic cirrhosis (AC) 16 cases]，100 patients with viral hepatitis [non-ALD (NALD) group] before treatment and after treatment for 3 weeks and 100 healthy subjects (control group). The changes of serum GGT，ALT，AST，m-AST activities were observed in AFL，AH and AC patients before and after treatment.  Results　The activities of serum GGT，ALT，AST and m-AST in ALD and NALD groups were significantly higher than those in control group (P<0.05)，and the activities in NALD group were significantly higher than those in ALD group (P<0.05). After the treatment，the GGT，ALT and AST activities in ALD group decreased significantly (P<0.001). The activities in AFL and AH groups decreased more significantly than those in AC group. After the treatment，the GGT，ALT，AST and m-AST activities decreased basically to the normal levels in AFL group. The m-AST activity decreased significantly in AH group，while the m-AST activity decreased not significantly in AC group.  Conclusions　Serum m-AST has clinical significance in monitoring ALD.

Key words: Aspartate aminotransferase, Isoenzyme, Alcoholic liver disease