Diagnostic potential of serum matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 as non-invasive markers of hepatic fibrosis in patients with HCV related chronic liver disease

Abstract

As chronic liver disease progresses, an imbalance occurs between synthesis and breakdown of extracellular matrix (ECM). Matrix metalloproteinases (MMPs) are involved in degrading ECM while tissue inhibitors of metalloproteinases (TIMPs) prevent their fibrolytic action. In the present study, serum levels of matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were investigated as non-invasive parameters for the diagnosis of hepatic fibrosis in patients with HCV related chronic liver disease. Their diagnostic potential was evaluated in comparison to hepatic histology and standard liver function tests. A sandwich enzyme immunoassay technique was used to study circulating values of MMP-2 and TIMP-1 in forty-one patients with HCV antibodies in their sera (27 patients with biopsy ascertained chronic hepatitis C and 14 patients with histologically proven liver cirrhosis. Hepatic histology was evaluated using the hepatitis-activity-index according to Ishak et al. (1995), quantifying separately inflammatory activity and fibrosis. Ten healthy individuals were also included in the study as controls. Serum levels of MMP-2 were similar in controls and in chronic hepatitis C patients with (n = 15) and without (n = 12) fibrosis, but increased significantly in cirrhosis. TIMP-1 serum values showed a steady increase from normal controls to chronic hepatitis C without fibrosis, hepatitis C with fibrosis, and cirrhosis. The diagnostic potential of MMP-2 to detect fibrosis was low with a sensitivity of 7% and a diagnostic efficiency of 56%. The diagnostic potential of circulating MMP-2 to detect cirrhosis was higher with a sensitivity of 83% and a specificity of 96% resulting in a diagnostic efficiency of 92%. Serum TIMP-1 values detected fibrosis with a sensitivity of 67% and a specificity of 69% resulting in an efficiency rate of 70%. TIMP-1 values detected cirrhosis with 100% sensitivity but only 75% specificity. The diagnostic potential of circulating TIMP-1 was higher than that of serum ALT, AST or albumin values. In conclusion, serum values of MMP-2 and TIMP-1 are able to detect cirrhosis with a high sensitivity. Moreover, TIMP-1 values can detect fibrosis with comparable efficiency. Regular determinations of both TIMP-1 and MMP-2 in patients with chronic hepatitis C may be used as indicators of increasing fibrosis and the development of cirrhosis.