Detection of high levels of Survivin-immunoglobulin M immune complex in sera from hepatitis C virus infected patients with cirrhosis.

Aim: The identification and surveillance of patients with liver dysfunctions and the discovering of new disease biomarkers are needed in the clinical practice. The aim of this study was to investigate on Survivin-immunoglobulin (Ig)M immune complex (IC) as a potential biomarker of chronic liver diseases.

Methods: Serum levels of Survivin-IgM were measured using an enzyme-linked immunoassay that had been standardized and validated in our laboratory in 262 individuals, including healthy subjects and patients with chronic viral hepatitis, cirrhosis and hepatocellular carcinoma (HCC).

Results: Survivin-IgM IC was lower in healthy subjects (median, 99.39 AU/mL) than in patients with chronic viral hepatitis (median, 148.03 AU/mL; P = 0.002) or with cirrhosis (median, 371.00 AU/mL; P < 0.001). Among patients with cirrhosis, those with hepatitis C virus (HCV) infection showed the highest level of Survivin-IgM IC (median, 633.71 AU/mL; P < 0.001). The receiver-operator curve analysis revealed that Survivin-IgM accurately distinguishes HCV correlated cirrhosis from chronic viral hepatitis (area under the curve [AUC], 0.738; sensitivity, 74.5%; specificity, 70.7%). A multivariate logistic regression model, including Survivin-IgM IC, aspartate aminotransferase (AST) and AST/alanine aminotransferase (ALT) ratio increased the prediction accuracy for the identification of the cirrhotic HCV patients (AUC, 0.818; sensitivity, 87.2%; specificity, 65.9%). Conversely, Survivin-IgM IC significantly decreased in HCC patients (median, 165.72 AU/mL; P = 0.022).

Conclusion: Our results suggest that Survivin-IgM immune complex may be used as a potential biomarker for liver damage, particularly for the identification of the HCV-related cirrhotic population.