The present study aims to compare serum metabolite alterations between acute-on-chronic liver failure (ACLF) and chronic liver failure (CLF), and find the specific biomarkers associated with the diseases.

Serum samples were collected from patients with ACLF (n=76) and CLF (n=56) as well as healthy individuals (n=20) and assayed by ultra-performance liquid chromatography mass spectrometry (UPLC–MS). The acquired data was analyzed using principal components analysis (PCA) and partial least squares discriminate analysis (PLS-DA).

The PLS-DA model with satisfactory explanatory and predictive ability (R2=0.979, Q2=0.918) is capable of discriminate ACLF patients from CLF patients. Significant difference in the metabolomics among the three groups was observed, metabolites that decreased significantly in the serum of ACLF and CLF included phosphatidylcholines (PCs) and lysophosphatidylcholines (LPCs), whereas conjugated bile acids (GCDCA, GUDCA) increased significantly, these metabolites considered as common biomarkers of liver failure. Linoleyl carnitine showed significant increase in CLF compared with controls while no significant change was observed in ACLF, it could be special biomarkers of ACLF and CLF.

Metabolomics based on ultra-performance liquid chromatography mass spectrometry provide a new way to diagnose and reveal the pathogenesis of ACLF and CLF.