High AST/ALT ratio may indicate advanced alcoholic liver disease rather than heavy drinking.

AIMS To assess the place of AST/ALT ratio (the ratio of serum aspartate aminotransferase to serum alanine aminotransferase) as a diagnostic marker in medical populations. METHODS Laboratory tests were viewed retrospectively in three groups of patients: 313 patients with alcohol dependence, consecutively admitted to an alcohol and drug treatment unit for treatment of withdrawal (W) symptoms, 78 patients with alcohol abuse or dependence consecutively admitted to surgical or medical wards with various primary somatic (S) diagnoses (e.g. respiratory, gastrointestinal and metabolic), and 48 consecutive patients with alcohol abuse or dependence admitted to surgical or medical wards for treatment of alcohol-related liver cirrhosis and its complications (C). Comparison between groups was made of the pattern of patients' AST/ALT ratios using, for Groups S and C, laboratory data from patients' first admission for their condition. RESULTS There was a significant rise in the AST/ALT ratio from the W to the S patients, and from the S to the C patients. In the W group, the ratio was < or = 1.0 in 64% of the patients, and only exceptionally > or = 2. In the C group, 69% had a ratio > or = 2, and 8% a ratio < or = 1.0. The mean ratio was midway in the S group. In the C group, there was a progressive decline in aspartate (AST/ALT) ratios after admission. CONCLUSIONS Most patients with high alcohol consumption but without severe liver disease do not have an AST/ALT ratio above 1. High AST/ALT ratio suggests advanced alcoholic liver disease.