Gut microbiota dysbiosis in alcoholic fatty liver disease: distinct microbial communities and biochemical alterations.

Objectives: To compare the gut microbiota composition among patients with alcoholic fatty liver disease (AFLD), individuals with alcohol use disorder (AUD) without liver damage, and healthy controls, and to investigate correlations between microbial profiles and liver health.

Methods: A retrospective analysis was conducted on 34 participants: 14 with AFLD, 10 with AUD without liver damage, and 10 healthy controls. Blood biochemical markers, liver function tests, lipid profiles, and gut microbiota composition were assessed. Gut microbiota was analyzed via high-throughput 16S rRNA gene sequencing. Alpha and beta diversity indices were calculated, and group-specific microbial taxa were identified.

Results: AFLD patients showed a decreased Firmicutes/Bacteroidetes ratio and an increased abundance of Bacteroidetes, indicating gut dysbiosis compared to the other groups. Biochemical markers, including triglycerides, alanine aminotransferase, gamma-glutamyl transferase, and cholinesterase, were significantly altered in AFLD patients (all P > 0.05). Beta diversity analysis revealed distinct microbial communities in the AFLD group. Notably, taxa such as Megamonas and Selenomonadales were enriched in AFLD, while beneficial genera like Ruminococcus and Faecalibacterium were significantly reduced.

Conclusion: AFLD is associated with marked gut microbiota alterations and distinct microbial signatures, which correlate with liver dysfunction and biochemical abnormalities, highlighting the role of dysbiosis in disease pathogenesis.