Lipocalin-2 levels increase in plasma of non-alcoholic fatty liver disease patients with metabolic syndrome

Introduction Non-alcoholic fatty liver disease (NAFLD) has emerged as major health risk in metabolic syndrome. The liver biopsy is the golden standard for the diagnosis and differentiation of all NAFLD stages, but its invasiveness poses a risk for patients, which is why new, non-invasive ways of diagnostics ought to be discovered. Lipocalin-2 (LCN2), which is a part of the lipocalin transport protein family, is a protein formally known for its role in iron transport and in inflammatory response. In the present study, we evaluated the levels of LCN2 a marker of liver inflammation and injury in the blood of patients with ultrasonography proven NAFLD. Materials and methods A total of 94 (24 control and 70 cases with different grade of NAFLD) aged and sex matched patients participated in the single-centre, open, hospital-based case control cross-sectional study. All anthropometric, biochemical and hematological assessment was done after proper consent. The metabolic syndrome was determined by new IDF criteria. Plasma LCN2 levels were measured by ELISA method. Results The LCN2 levels were increased in patients with NAFLD (170.38±114.43 ng/ml) as compared to healthy volunteers (40.46±6.44 ng/ml) ( p <0.001). The LCN2 levels increase as the level of steatosis increases from grade I (143.99±90.04), grade II (205.78±143.07) to grade III (219.49±146.30) of fatty liver even though there was no difference in BMI showing it is specific to liver injury than obesity. The ROC curve analysis predicted sensitivity of 96.9% and predicted specificity of 91.7%. These changes were detected before derangement in liver enzymes. Conclusion The plasma lipocalin levels increase in NAFLD with metabolic syndrome and it can be considered a good blood biomarker. The early detection in NAFLD cases may improve prognosis.