Correlation between laboratory findings and ultrasonography in patients with non-alcoholic fatty liver disease

Objective: The aim of this study is to evaluate the correlation between qualitative, quantitative sonographic data and laboratory-based parameters used in hepatosteatosis grading, thereby assessing their role in determining the severity of hepatosteatosis. Materials and Methods: In this retrospective study, sonographic data of patients diagnosed with hepatosteatosis who underwent ultrasound examinations at the Radiology Department of Adıyaman University Training and Research Hospital between August 2023 and August 2024 were analyzed. A total of 354 participants underwent B-mode ultrasound, USAT (Ultrasound Attenuation Technology), HRI (Hepatorenal Index), and LTI (Liver Texture Index) measurements performed by a single operator. Additionally, laboratory parameters obtained from venous blood samples collected on the same day as the ultrasound examination were analyzed, and the ALT/AST ratio, FLI (Fatty Liver Index), and HSI (Hepatic Steatosis Index) were calculated. In this study, the correlation between sonographic and laboratory parameters was assessed according to B-mode ultrasound grading. The Kruskal-Wallis H test was used for non-normally distributed variables, and multiple comparisons were conducted using the Bonferroni-corrected Z test. Categorical variables were analyzed using the Chi-square test, and in cases where expected values were below 5, Fisher's Exact Test was applied. Cut-off values for variables associated with liver steatosis were determined using ROC analysis. Results: As B-mode ultrasound grading increased, the proportion of males, BMI, and the prevalence of Type 2 diabetes significantly increased (p<0.001). AST, ALT, AST/ALT ratio, GGT, triglycerides, and liver size also showed significant increases with higher B-mode grades (p<0.001). A significant correlation was found between B-mode grading and HSI, FLI, HRI, USAT and LTI scores (p<0.001).According to ROC analysis, the strongest diagnostic markers were USAT, FLI and LTI. USAT demonstrated the highest diagnostic accuracy, making it a reliable non-invasive tool for grading hepatosteatosis. FLI was identified as an effective marker based on biochemical parameters. LTI was shown to be a strong ultrasonographic index for evaluating hepatic parenchymal changes. Conclusion: The strong correlation observed between USAT, LTI, and the laboratory-based FLI suggests that these parameters can be effectively utilized in hepatosteatosis evaluation. Due to their non-invasive nature, USAT, LTI, and FLI represent promising alternatives to gold-standard diagnostic methods such as MR-PDFF and liver biopsy in the coming years. However, since this study was conducted by a single operator and involved a limited patient population, further multicenter studies with larger cohorts and multiple operators are required to validate these findings. Keywords: Hepatosteatosis, ultrasound attenuation, LTI, FLI, HSI, ALT/AST