Abstract: Objective To investigate the value of instantaneous elastic imaging system (FibroScan) and hepatic fibrosis index in evaluating hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) complicated with hepatitis B virus (HBV). Methods The clinical data of 93 patients with NAFLD with comorbid HBV infection admitted from June 2021 to June 2023 were retrospectively analyzed. According to pathological examination there were 70 cases with mild to moderate fibrosis and 23 cases with severe fibrosis. The general and clinical data of these patients were collected, including gender, age, body mass index (BMI), diabetes mellitus, hypertension, alcohol consumption, smoking, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), platelets (PLT), albumin (ALB), hepatitis B virus e antigen (HBeAg), NAFLD fibrosis score (NFS), liver stiffness measurement (LSM) and liver fibrosis index-4 (FIB-4). The risk factors of severe liver fibrosis in patients with NAFLD and HBV infection were analyzed by unconditional Logistic stepwise regression; Receiver operating characteristic curve (ROC) was used to analyze the value of LSM and FIB-4 in evaluating liver fibrosis in NAFLD patients with HBV infection; Spearman correlation coefficient was used to analyze the correlation between LSM, FIB-4 and liver fibrosis stage in NAFLD patients with HBV infection. Results The levels of ALT, AST, NFS, LSM and FIB-4 in mild to moderate group were (41.76±8.52)U/L, (31.58±8.07)U/L, (-2.62±0.71)g/dL, (5.75±1.24)kPa, and (1.21±0.39)], which were significantly lower than those of (61.89±7.33)U/L, (45.36±12.94)U/L, (-1.44±0.45)g/dL, (10.71±2.97)kPa, and (1.88±0.62) in severe group. The level of PLT in mild to moderate group was (177.26±48.31) 10⁹/L], which was significantly higher than that of 138.74±41.65)10⁹/L in severe group (P<0.05). There was no significant difference in gender, age, BMI, diabetes, hypertension, drinking, smoking, ALB and HBeAg between the two groups (P>0.05). By multiple logistic regression analysis it was confirmed that ALT, AST, PLT, NFS, LSM and FIB-4 were risk factors for severe liver fibrosis in patients with NAFLD and HBV infection (P<0.05). The results of correlation analysis showed that LSM and FIB-4 were positively correlated with liver fibrosis stage in patients with NAFLD and HBV infection (r=0.614, 0.583), and all P<0.05. By ROC curve analysis it was showed that the area under the curve (AUC) of LSM and FIB-4 in evaluating severe liver fibrosis was 0.853 and 0.842, respectively, and P<0.05. The AUC of the combined evaluation of the two methods for severe liver fibrosis in patients with NAFLD and HBV infection was 0.888, the sensitivity was 0.826, and the specificity was 0.929. Conclusion Both FibroScan and liver fibrosis index have a certain value in evaluating liver fibrosis in NAFLD patients with comorbid HBV infection, and the efficacy of a combined evaluation is higher.

Key words: Nonalcoholic fatty liver disease, Liver fibrosis, Instantaneous elastic imaging system, Liver fibrosis index