RESULTS: Serum CK18-F levels showed a positive correlation with histologic steatosis (ρ = 0.271, P = 0.0033),
inflammation (ρ = 0.353, P = 0.0005), ballooning (ρ = 0.372, P = 0.0001), and the total
NAS (ρ = 0.474, P = 2.68 × 10-7). The serum CK18-F level was significantly lower for NAFL (
NAS ≤ 2) than for borderline NASH (
NAS of 3-4) or definite NASH (
NAS ≥ 5) (P = 0.0294, P = 1.163 × 10-5, respectively). The serum CK18-F level was significantly higher for definite NASH than for borderline NASH (P = 0.0002). The area under the receiver operating characteristic curve of serum CK18-F to predict the presence of NAFL and definite NASH was 0.762 and 0.757, respectively. The optimal cut-off point of serum CK18-F for NAFL and definite NASH was 230 and 270 U/L, respectively. The sensitivity, specificity, positive predict value, and negative predict value of serum CK18-F for NAFL were 0.89, 0.65, 0.34, and 0.97, and those for definite NASH were 0.64, 0.76, 0.72, and 0.67, respectively. Accuracies of diagnosis for both NAFL and definite NASH were 0.70.
CONCLUSIONS: