Abstract: Objective This study was conducted to investigate the diagnostic performance of ultrasound attenuation parameter (UAP) combined with serum plasminogen activator inhibitor-1 (PAI-1) and alanine aminotransaminase (ALT) levels in evaluating severe hepatic steatosis in patients with metabolic associated fatty liver disease (MAFLD). Methods 112 patients with MAFLD were admitted to our hospital between March 2019 an December 2022, and all patients underwent liver biopsy and transient elastography for UAP detection. Serum PAI-1 level was measured by ELISA. The diagnostic efficacy was analyzed by using the receiver operating characteristic (ROC) curve. Results Out of the 112 patients with MAFLD, the liver histopathological examination showed mild liver steatosis in 45 cases, moderate in 42 cases and severe in 25 cases; the BMI, serum TC, TG and LDL-C levels in patients with severe liver steatosis were (32.6±2.4)kg/m², (6.6±0.9)mmol/L, (4.6±1.4)mmol/L and (4.0±0.9)mmol/L, significantly higher than [(27.6±1.9)kg/m², (5.8±0.8)mmol/L, (3.5±0.9)mmol/L and (3.5±0.7)mmol/L, respectively, P<0.05] in patients with moderate or [(24.1±0.9)kg/m², (5.1±0.7)mmol/L, (2.2±0.7)mmol/L and (3.0±0.5)mmol/L, respectively, P<0.05] in mild, while serum HDL-C level was (1.2±0.2)mmol/L, significantly lower than [(1.4±0.2) mmol/L, P<0.05] in moderate or [(1.4±0.2)mmol/L, P<0.05] in mild liver steatosis; the UAP, serum PAI-1 and ALT level in patients with severe steatosis were (312.7±32.6)dB/m, (36.5±4.2)mg/mL and (72.1±7.4)U/L, much higher than [(284.2±30.1)dB/m, (28.1±3.4)mg/mL and (36.3±4.1)U/L, P<0.05] in moderate or [(257.4±26.4)dB/m, (20.4±2.4)mg/mL and (23.7±2.5)U/L, P<0.05] in mild steatosis; the ROC analysis showed that the AUC, sensitivity (Se) and specificity (Sp) were 0.914(95%CI:0.883-0.990), 89.6% and 93.3%, with the Sp superior to any single parameter evaluation (P<0.05) by the combination of UAP and serum PAI-1 and ALT level in predicting severe liver steatosis. Conclusion We recommend the combination of UAP and serum PAI-1 and ALT level in predicting severe hepatic steatosis in patients with MAFLD, which might provide a scientific clue for clinical management.

Key words: Metabolic associated fatty liver diseases, Liver steatosis, Ultrasound attenuation parameter, Plasminogen activator inhibitor 1, Alanine aminotransaminase, Diagnosis