Non-invasive markers for the prediction of fibrosis in chronic hepatitis C infection

Liver fibrosis occurs as a result of chronic liver injury and is the hallmark of chronic liver disease. The final stage of progressive liver fibrosis is cirrhosis, which is implicated in portal hypertension, end-stage liver disease and hepatocellular carcinoma. Liver biopsy has historically been the gold standard test for the assessment of liver fibrosis for liver diseases such as viral hepatitis, autoimmune hepatitis and primary biliary cirrhosis. Improved serological tests have enhanced the diagnosis of these conditions and reduced the need for liver biopsy. Liver biopsy is unpopular among patients and clinicians. It is associated with morbidity and mortality, and in addition is subject to sampling error, inter- and intra-observer variability. There is therefore a need for non-invasive markers of liver fibrosis that are accurate, reliable, cheap and easy to use. The aim of this review is to examine the different non-invasive methods that can be used to estimate the severity of fibrosis. The methods evaluated include clinical examination, routine laboratory investigations, imaging tests, specialized tests of liver function and finally serum extra-cellular matrix markers of fibrosis. The review mainly focuses on fibrogenesis in the context of chronic hepatitis C infection.