Wisteria floribunda agglutinin-positive Mac-2-binding protein and type 4 collagen 7S: useful markers for the diagnosis of significant fibrosis in patients with non-alcoholic fatty liver disease

Background and AimThe fibrosis stage of liver is associated with the long-term outcomes in patients with non-alcoholic fatty liver disease (NAFLD). However, significant fibrosis, defined as fibrosis stages 2-4, is associated with an elevated risk of progression to severe liver disease; there have been scant reports about diagnosing significant fibrosis. We compare the noninvasive method and aim to identify appropriate liver fibrosis markers for detecting significant fibrosis in NAFLD patients. MethodsWe compared the usefulness of liver fibrosis markers (Wisteria floribunda agglutinin-positive Mac-2-binding protein [WFA(+)-M2BP], type 4 collagen 7S, etc.), clinical scoring systems, and liver stiffness measurement obtained using vibration-controlled transient elastography and magnetic resonance imaging-based magnetic resonance elastography in the same individuals and identified the most appropriate noninvasive method for detecting significant fibrosis in 165 patients with liver biopsy-diagnosed NAFLD. ResultsThe area under the receiver operating characteristic curve based on the serum cutoff index values of WFA(+)-M2BP/the serum levels of type IV collagen 7S for the diagnosis of significant fibrosis was 0.832 (95% confidence interval: 0.771-0.894)/0.837 (95% confidence interval: 0.778-0.898). WFA(+)-M2BP (cutoff index)0.83 or type IV collagen 7S5.2ng/mL showed a high sensitivity (91.4%) and negative predictive value (87.9%) for the diagnosis of significant fibrosis. ConclusionsWe showed that serum WFA(+)-M2BP or type IV collagen 7S levels serve as useful independent markers for detecting significant fibrosis and that use of both WFA(+)-M2BP and type IV collagen 7S together increased the sensitivity and negative predictive value for the diagnosis of liver fibrosis. These results need to be validated in larger populations from multiple clinical centers.