Biomarkers From the Microbiome to Predict ALD Progression and Its Severity: A Comprehensive Review

Alcohol use is a major global health issue, causing about 3.3 million deaths each year, or roughly 5.9% of all deaths worldwide. Alcohol-related liver disease develops in stages: steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. If alcohol consumption is discontinued at early stages, alcohol-related fatty liver disease can be reversed; however, continued exposure leads to progressive liver injury and increased mortality risk. Current diagnostic tools lack sufficient sensitivity and specificity to detect early-stage disease or accurately assess disease progression. This highlights the need for reliable and mechanistically relevant biomarkers for early diagnosis and staging. This review examines alterations in gut microbiota across different stages of alcohol-associated liver disease and evaluates gut microbiota-associated biomarkers, including microbial metabolites, in the context of their potential diagnostic and prognostic utility. In addition, the review discusses the limitations of existing biomarkers and highlights the emerging role of microbiome-derived signals in reflecting disease mechanisms. These findings suggest that gut microbiota-related biomarkers may provide a promising but still evolving approach for improving early detection and understanding disease progression in alcohol-associated liver disease.