Diagnostic role of the fibrosis-4 index and nonalcoholic fatty liver disease fibrosis score as a noninvasive tool for liver fibrosis scoring

Nonalcoholic fatty liver disease (NAFLD) is characterized by liver fibrosis, which serves as a crucial indicator of its progression and prognosis. Owing to the limitations of biopsy, which is the gold standard for measuring liver fibrosis, a reliable and noninvasive marker is required. We evaluated the diagnostic role of the fibrosis-4 (FIB-4) index and nonalcoholic fatty liver disease fibrosis score (NFS) in patients with NAFLD with varying severities of liver fibrosis. The FIB-4 index and NFS were calculated using laboratory data from 121 patients who underwent liver biopsies between January 2022 and December 2023. The results were compared with those of the Scheuer scoring system for liver biopsies (F0, F1 + F2, and F3 + F4) to determine the sensitivity and specificity of the FIB-4 index and the liver disease fibrosis score in detecting and staging liver fibrosis. Twenty-one patients had advanced fibrosis (F3-F4), and 100 had minimal or mild fibrosis (F0-F2). The degree of liver fibrosis increased with decreased albumin, alanine aminotransferase and platelet count levels, and increasing age. Receiver operating characteristic curve analysis for the FIB-4 index and NFS revealed that the areas under the curve for the FIB-4 index and NFS were 0.895 (95% confidence interval: 0.836-0.954) and 0.882 (95% confidence interval: 0.813-0.952), respectively. The FIB-4 indices showed 95.24% sensitivity at a cutoff point of 1.30, and 85% specificity at a cutoff point of 2.67, while the NFS indices showed 95.24% sensitivity at -1.455 cutoff point and 95% specificity at a cutoff point of 0.676. The FIB-4 index and NFS may replace biopsy for the detection of fibrosis in patients with NAFLD.