The Benefit of Bariatric Surgery on Histological Features of Metabolic Associated Fatty Liver Disease Assessed Through Noninvasive Methods

Background In patients with clinically severe obesity, metabolic associated fatty liver disease (MAFLD) and steatohepatitis are highly prevalent. There is a lack of prospective studies evaluating the impact of bariatric surgery (BS) on MAFLD using both noninvasive and histological criteria. The present study aims to assess the impact of BS on MAFLD using histological and biochemical criteria. Methods This is a prospective study of 52 patients subjected to BS. Noninvasive fibrosis risk scores (NIFRS) along with anthropometric, clinical, and biochemical parameters were recorded pre- and 12 months post-BS. Liver biopsy was obtained in all individuals at baseline (wedge biopsy) and was repeated at 12 months (percutaneous Tru-cut) in those diagnosed with steatohepatitis. The primary outcome was the change in the degree of steatohepatitis and fibrosis. The secondary outcome was the change in scores for hepatocellular ballooning, lobular inflammation, steatosis, and fibrosis. Results One year after BS, steatohepatitis resolved in core biopsies with no worsening of fibrosis in 95.7% of individuals ( n = 21, 95% CI: 87.3–100), and 13 (56.5%) exhibited complete resolution. Of 15 patients with fibrosis at baseline, 13 (86.7%) showed improvement and 12 exhibited fibrosis resolution. The values of transaminases improved, but only gamma glutamyl transferase (GGT) showed statistical significance. Among the NIFRS, NAFLD fibrosis score (NFS) and Hepamet fibrosis score (HFS) showed significant improvement. Conclusions In the setting it was studied, BS improved or resolved steatohepatitis and fibrosis in patients with obesity. NIFRS, especially NFS and HFS, and levels of GGT could be used as markers of recovery of liver function after BS. Graphical abstract