Noninvasive markers of liver fibrosis in alcoholic liver disease (ALD) are crucial to establish early intervention. Previous studies have suggested that plasma levels of cleaved keratin-18 (K18; M30) fragments can predict the severity of liver disease. The aim of this study was to correlate plasma M30 levels with stages of liver fibrosis in ALD.
Patients with ALD (n=139, 79.1% males) and liver histology were included, and plasma samples were collected to quantify plasma M30 levels. Patients were stratified into five groups by fibrosis stage (F0=14; F1=15; F2=35; F3=17; and F4=58) according to the Kleiner score. Differences between groups were evaluated using the chi-square test or analysis of variance. Trends by fibrosis stage were calculated by logistic regression analysis, and sensitivity, specificity and positive and negative predictive values were determined.
There were no significant differences in M30 levels among fibrosis stages. The correlation between plasma M30 levels and fibrosis was poor (Pearson’s correlation coefficient=0.13, Spearman rho=0.20 [p=0.02]), and M30 levels did not correlate with alcohol-specific histological features. However, significant correlations of M30 levels with aspartate aminotransferase (Spearman rho=0.653, p<0.001) and alanine aminotransferase (Spearman rho=0.432, p<0.001) were found. M30 levels of >200 U/L reveal a sensitivity for predicting cirrhosis of 84.5% with a negative predictive value of 73.5%.
Plasma M30 levels are often elevated in ALD and correlate with serum transaminases but do not reflect fibrosis. The usefulness as a prognostic marker awaits evaluation in prospective studies.