Diagnostic accuracy of FibroScan-AST (FAST) score, non-alcoholic fatty liver fibrosis score (NFS), FibroScan, and liver fibrosis index (FIB-4) for identifying fibrotic non-alcoholic steatohepatitis in patients with chronic hepatitis B with metabolic dysfunction-associated fatty liver disease

Objective: To evaluate the diagnostic value of the FibroScan-AST (FAST) score, non-alcoholic fatty liver fibrosis score (NFS), FibroScan, and liver fibrosis index (FIB-4) for identifying fibrotic non-alcoholic steatohepatitis (NASH) in patients with chronic hepatitis B (CHB) with metabolic dysfunction-associated fatty liver disease (MAFLD). Methods: All patients with CHB and MAFLD who underwent liver biopsy at the Zhenjiang Third Hospital affiliated with Jiangsu University between August 2010 and December 2022 were included in the analysis. The diagnostic accuracy of FAST, NFS, FibroScan, and FIB-4 for diagnosing NASH and liver fibrosis were evaluated based on the area under the receiver-operating characteristic curve (AUC). Results: A total of 156 patients with CHB combined with MAFLD were included, including 69 with NASH and fibrosis stage 2 or higher (NASH+F >= 2), and 16 with NASH and cirrhosis (NASH+F4). The AUC of FAST, NFS, liver stiffness measurement (LSM), and FIB-4 for diagnosing NASH+F >= 2 was 0.739 (p < 0.001), 0.643 (p = 0.006), 0.754 (p < 0.001), and 0.665 (p = 0.003), respectively. The specificity of FAST, NFS, LSM, and FIB-4 was 67%, 51.8%, 78.6% and 76.8%, respectively, and the sensitivity was 75%, 78.6%, 67.9%, and 53.6%, respectively. No significant differences were found between groups. The AUC of FAST, NFS, LSM, and FIB-4 for diagnosing NASH+F4 was 0.650 (p = 0.038), 0.725 (p = 0.001), 0.851 (p < 0.001), and 0.560 (p = 0.533), respectively. The specificity of the FAST, NFS, LSM, and FIB-4 was 55.9%, 50.0%, 71.6%, and 75.5%, respectively and the sensitivity was 80.0%, 100%, 100%, and 50.0%, respectively. The differences between AUCs of FIB-4 and FAST compared with LSM were 0.291 and 0.201, respectively (p < 0.05). Conclusion: In patients with CHB combined with MAFLD, FAST did not have better accuracy than NFS and FIB-4 for predicting fibrotic NASH, whereas LSM had better accuracy than FAST and FIB-4.