Objective: Non-alcoholic fatty liver disease (NAFLD) is affecting people worldwide with increasing prevalence. Non-invasive tests are required for both diagnosis and staging of the disease. We aimed to evaluate diagnostic accuracy of routine liver enzymes and cytokines in NAFLD.
Methods: A total of 88 cases, aged between 20 and 62 years, were included in the study. Serum ALT, AST, GGT, triglyceride, TNF-alpha, IL-6 and IL-8 were measured in 40 patients with NAFLD and in 48 healthy control patients with similar BMI and demographic characteristics. Diagnostic performances of serum biomarkers for diagnosis of NAFLD were evaluated with ROC analysis.
Results: ALT and AST showed good diagnostic performance in predicting patients with NAFLD in the overall group (AUC=0.817; 95% CI[0.721-0.913], AUC=0.815; 95% CI[0.718-0.911] respectively) but in obese subjects ALT and AST showed poor performance (AUC=0.659; 95% CI[0.478-0.841], AUC=0.680; 95% CI[0.498-0.861] respectively). Among cytokines TNF-alpha showed best performance in the diagnosis of NAFLD in both overall group and obese subjects (AUC=0.892; 95% CI[0.824-0.959], AUC=0.858; 95% CI[0.739-0.977] respectively). The optimal cut off value for TNF-alpha was 10.65pg/ml with a sensitivity of 75% and a specificity of 93% in the overall group. IL-6 and IL-8 showed poor performance.
Conclusion: TNF-alpha may be a good parameter for predicting patients with NAFLD.