Close correlation of liver stiffness with collagen deposition and presence of myofibroblasts in non-alcoholic fatty liver disease

Aim: Transient elastography is known as a rapid, objective, and highly reliable technique for staging hepatic fibrosis caused by hepatitis C virus infection; however, the relationship between degree of fibrosis and the collagen deposition or the accumulation of myofibroblasts in non-alcoholic fatty liver disease (NAFLD) remains to be further elucidated. Methods: The subjects were 36 patients with NAFLD who received liver biopsy and liver stiffness measurement using transient elastography. Their clinical data and laboratory values were collected. Morphometric analyses of liver fibrosis indicated by collagen deposition and the relative numbers of myofibroblasts were performed. Results: Liver stiffness measured by transient elastography correlated with histopathological fibrosis staging of NAFLD determined by Brunt's scoring system (P = 0.000149). The fibrosis staging correlated with the ratios of the Sirius redpositive area (P = 0.000032) and alpha-smooth muscle actin-positive area (P = 0.000898). Finally, liver stiffness significantly correlated with the ratios of the Sirius red-positive area (r = 0.390, P = 0.0184) and alpha-smooth muscle actin-positive area (r = 0.333, P = 0.0471). Conclusions: Liver stiffness measurement by transient elastography is valuable for evaluating fibrotic progression in NAFLD.