The Autobio procollagen type III N-terminal endopeptidase (PIIINP) chemiluminescence immunoassay (CLIA) is intended for the quantitative determination of PIIINP concentration in serum specimens, aiding in the diagnosis, monitoring and prognosis of hepatic fibrosis.
The formation of hepatic fibrosis is resulting from the over produce or deficient degradation, or both, of the extracelular matrix, hence excessive connective tissue builds up in the liver, then fibrosis is in turn formed. Hepatic fibrosis is the common pathological basis for chronic liver disorders. Various chronic liver disorders might gradually progress to hepatic fibrosis.
Various methods exist for the diagnosis of hepatic fibrosis, such as liver biopsy, imaging tests and serologic marker assays. The most reliable means to examine the extent of fibrosis and its activity is still the liver biopsy method. Although it is the Gold standard in hepatic fibrosis diagnosis, liver biopsy has many disadvantages. e.g. it is an invasive test, hence patients are reluctant to take this test and repeated tests are not able to be conducted. It is not possible to monitor the progress of the recovery and effects of the therapy. Fibrosis is characterized by focal inflammation and fibroelastosis, so deviations exist in specimen collection. Consequently, liver biopsy is much limited in clinical practice. Modern medical imaging methods such as type B ultrasound, CT, MRI etc. could observe certain symptoms of hepatic fibrosis. However, these medical imaging methods are yet to be confirmatory and identifiable, not to mention the inability to accurately determine the extent of liver fibrosis. Serological tests are able to identify different stages of liver fibrosis with relative accuracy, which indicates various changes during the development of liver fibrosis. Additionally, the effects of anti-fibrosis therapies could be monitored.
PIIINP is an N-terminal pre-peptide released to the blood stream when type III pre-collagen is transferred to type III collagen outside the cell by a specific enzyme, the quantity of which is equal to that of type III collagen. Consequently, the serum level of pre-collagen N-terminal peptide indicates the amount and velocity of type III collagen synthesis. The type III collagen mainly exists in the liver. Hence the serum level of pre-collagen N-terminal peptide indicates the extent of hepatic fibrosis and the activity of hepatic disorders. Type III pre-collagen N-terminal peptide is regarded as a serologic marker of hepatic fibrosis. The type III pre-collagen N-terminal peptide could effectively distinguish between light, medium and heavy hepatitis, indicate active chronic hepatitis, is an indicator of the activity and extent of chronic hepatic fibrosis. Type III pre-collagen N-terminal peptide levels in longitudinal serum samples could determine the prognosis of chronic hepatitis.
