The relationship between cytokeratin 18 and liver steatosis on ultrasound in nonalcoholic fatty liver disease

Introduction. Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western countries, characterized by increased fat infiltration in the liver without secondary causes. Aim. To correlate cytokeratin 18 (CK-18) levels and NAFLD fibrosis scores with liver steatosis assessed by ultrasound. Patients and methods. A cross-sectional study enrolled 42 individuals with liver steatosis and 18 individuals without liver steatosis by ultrasound, who presented to the Al-Faiha GIT center from March 2020 to May 2021. Ten milliliters of venous blood were drawn from each individual to measure serum cytokeratin 18 levels using immunoassay. Results. In our study, we found that the presence and severity of liver steatosis, as assessed by ultrasound, increased with higher body mass index and advanced age, regardless of gender. A significant association was also found between impaired glucose tolerance and liver steatosis (p = 0.0001). No significant differences were found in lipid profile or liver enzymes between individuals with and without liver steatosis. The study demonstrated a good correlation between cytokeratin 18 levels and liver steatosis grades assessed by ultrasound (P = 0.0001), with a cutoff value of 102.03 pg/ml. However, a poor correlation was observed between the NAFLD fibrosis score and liver steatosis (P = 0.088). Conclusion. Serum cytokeratin 18 levels demonstrated a strong correlation with ultrasound-assessed steatosis grades, in contrast to the NAFLD fibrosis score, which exhibited a weak association. However, the findings should be interpreted with caution due to the relatively small sample size and the absence of histological confirmation.