Electrical and Viscoelastic Parameters of Erythrocytes as a Part of Diagnostic Models for Differentiating Fatty Liver Disease of Mixed Genesis from Non-Alcoholic and Alcohol-Related Fatty Liver Disease

Abstract

Aim: creation of diagnostic models including electrical, viscoelastic parameters of erythrocytes to distinguish fatty liver disease of mixed etiology (metabolic + alcoholic) from non-alcoholic and alcoholic fatty liver disease.Materials and methods. We examined 46 men with non-alcoholic fatty liver disease (NAFLD), 43 men with alcoholic fatty liver disease (AFLD), as well as 54 men with fatty liver disease (FLD) of mixed genesis (metabolic + alcohol-related); average age of the patients included in the study made 48.4 ± 9.6 years. The diagnosis was established on the basis of liver ultrasound findings and FLI liver steatosis index with a fibrosis grade of F1 or less (FibroScan® 502, Echosens, France). The electrical and viscoelastic parameters of erythrocytes were investigated by the diagnostic technique of dielectrophoresis using an electrooptical cell detection system.Results. The most significant parameters for differentiating fatty liver disease of mixed genesis (metabolic + alcoholic) from NAFLD using the Volcano plot have turned out to be cell polarizability at a frequency of 106 Hz (p = 6.49 ×10-5), erythrocyte cell membrane capacity (p = 0.00077), relative polarizability (p = 0.001), the levels of which were higher in patients with NAFLD. On the contrary, the index of red blood cells destruction at 105 Hz was higher in FLD of the mixed genesis (p = 0.047) and the crossover frequency was shifted to the high frequency range more than in NAFLD (p = 0.0005). The discriminant analysis has additionally revealed the significance of the degree of erythrocyte deformation at 5 ×105 Hz in distinguishing between mixed-genesis FLD and NAFLD. In differentiating FLD of mixed genesis from NAFLD, a diagnostic model incorporating the above red blood cells parameters has provided an AUC of 0.829 (confidential interval: 0.742–0.916), sensitivity of 80.9 %, and specificity of 83.3 %. Two indicators of red blood cells have been established that statistically significantly distinguish the mixed-genesis FLD from the AFLD (Volcano plot); these are the index of red blood cells destruction at a frequency of 5 ×105 Hz, which was higher with AFLD (p = 0.0007), and the capacity of cell membranes, the value of which prevailed in mixed-genesis FLD (p = 0.011). When distinguishing the mixed-genesis FLD from the AFLD, the combined model with the inclusion of three parameters of red blood cells, namely the index of red blood cells destruction at a frequency of 5 ×105 Hz, the capacity of erythrocyte membranes, and polarizability at a frequency of 106 Hz, has shown the highest levels of diagnostic accuracy, namely AUC = 0.751 (confidential interval: 0.611–0.908) with a sensitivity of 79.5 %, specificity of 74.7 %.Conclusion. The electrical and viscoelastic parameters of erythrocytes studied using the diagnostic technique of dielectrophoresis should be considered as promising biomarkers for the diagnosis of diffuse liver disease.