Non-invasive predictive score of fibrosis stages in chronic hepatitis C patients based on epithelial membrane antigen in the blood in combination with routine laboratory markers

Aim: The epithelial membrane antigen (EMA) could detect small deposits of liver malignant cells. However, no information exists regarding the use of EMA in patients with chronic hepatitis C (CHC). Therefore, we attempted to evaluate the diagnostic performance of EMA to distinguish patients with different liver fibrosis stages. Methods: Epithelial membrane antigen was identified in sera of 154 CHC patients using Western blot and enzyme linked immunosorbent assay (ELISA). Multivariate discriminant analysis (MDA) and receiver operating characteristic (ROC) curve analyses were used to create a predictive model including EMA in addition to a panel of routine blood markers. A combination algorithm was developed and validated prospectively in 170 CHC additional patients. Results: Epithelial membrane antigen at 130 kDa was identified, purified and quantified in sera of CHC patients using ELISA. Based on these encouraging results, we purified and developed a direct ELISA for the quantitation of EMA in sera of CHC. MDA selected a score for the prediction of significant liver fibrosis patients based on measurements of EMA, aspartate aminotransferase to platelet ratio index and albumin. Areas under the ROC curves (AUC) of the score for the three biomarkers were 0.82 for patients with liver fibrosis (F1–F4), 0.86 for significant liver fibrosis (F2–F4), 0.87 for advanced liver fibrosis (F3–F4) and 0.86 for liver cirrhosis (F4). The results of the validation study demonstrated that (74%) of patients could have avoided liver biopsy. Conclusion: This score was validated for the prediction of liver fibrosis stages and may minimize the need for liver biopsy.