Clinical Use

Assessment of type III collagen metabolism for diagnosis or treatment, and monitoring therapy that may increase risk of fibrosis/cirrhosis.


Type III collagen is derived from a larger protein, type III procollagen, which has propeptide extensions at both ends of the molecule. Some of the aminoterminal propeptides are set free during the synthesis and deposition of type III collagen, and some are retained in the molecules which remain on the surface of the collagen fibrils. This antigen, when found in serum, can thus be derived from the synthesis (including late processing) of new type III collagen, or from the degradation of existing type III collagen fibrils.

Increased concentrations of PIIINP are found in a number of conditions where accumulation and/or degradation of connective tissue takes place, e.g. in fibroproliferative, haematological, endocrinological and malignant diseases. Thus the changes in PIIINP are not specific for a particular disease, but reflect the involvement and altered metabolism of type III collagen.

Liver fibrosis and cirrhosis of various aetiologies increase serum concentrations of PIIINP. The magnitude of the change seems to be greater when there is inflammation than when there is only silent accumulation of connective tissue.

Sample requirements: Serum
Sample volume: 0.5 mL
Specimen Requirements: None

SAS Centres providing PIIINP analysis: