Total Keratin-18 (M65) as a Potential, Early, Non-Invasive Biomarker of Hepatocyte Injury in Alcohol Intoxicated Adolescents—A Preliminary Study

Background: Underage drinking is associated with health risk behaviors. Serum keratin-18 (CK18) levels are increased in liver diseases and may be biomarkers of outcome. The purpose of this study was to determine if the total CK18 (M65) or caspase-cleaved CK18 (M30) levels were different in adolescents admitted to hospital because of alcohol intoxication and controls with excluded liver diseases. Methods: A prospective study included 57 adolescents after alcohol use and 23 control subjects. The concentrations of M30 and M65 in the serum samples were evaluated using an enzyme-linked immunosorbent assay. Results: The median age was 15 (14–17) years and 49% were male. There were significant differences in M65 levels between the study and control groups (p = 0.03). The concentrations of M30 and M65 were insignificant in adolescents divided into subgroups according to blood alcohol concentrations (BAC). Significant positive correlations were found between BAC and M65 levels (p = 0.038; r = 0.3). In receiver operating characteristic (ROC) analysis M65 (cut-off = 125.966 IU/l, Se = 70.2%, Sp = 43.5%) allowed to differentiate between patients with and without alcohol intoxication (AUC = 0.66, p = 0.03). Conclusion: M65 appears to be a promising non-invasive biomarker of hepatocyte injury during alcohol intoxication in adolescents. Moreover, a higher concentration of M65 may indicate early organ injury before the increase in the activity of liver enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST).