FIB-4 Score as a Useful Screening Test for Diagnosing Liver Fibrosis

ABSTRACT

BACKGROUND: Liver biopsy is the gold standard for assessing liver fibrosis; however, it has a relatively high risk of resulting in complications. Although a non-invasive method (i.e., transient elastography—fibroscan) was introduced, it is expensive and is dependent on the patient's status. Thus, the FIB-4 score, a non-invasive formula, has been used to predict the degree of liver fibrosis. The aim of this study was to evaluate the usefulness of the FIB-4 score in predicting stages of liver fibrosis. METHODS: We analysed the age, diagnosis, and liver stiffness of 282 patients by measuring the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) as well as their platelet count. Liver elasticity was evaluated by two classification criteria (Foucher et al. and Mueller et al.). The FIB-4 score was calculated using the formula: age×AST/(platelet count×ALT½). The cut-off value of the FIB-4 score was determined according to the area under the relative operating characteristic curve (AUC) based on liver elasticity. RESULTS: The FIB-4 cut-off values, as determined using two different criteria, have the highest AUC, thereby indicating a robust ability to distinguish between healthy liver tissue and the presence of any liver fibrosis. The FIB-4 score with a cut-off value of 2.07, as determined by Mueller et al., had the highest AUC (0.837) and odds ratio (2.741) with a sensitivity of 78.3% and a specificity of 76.5%. CONCLUSIONS: An FIB-4 score of 2.07 is a cut-off value that is useful in detecting fibrotic progression in chronic liver disease in our laboratory. Each laboratory should determine an appropriate FIB-4 cut-off value that is relative to the particular characteristics of their patient population.