Serum aminoterminal procollagen type III peptide in acute viral hepatitis. A long-term follow-up study.

The development of chronic viral liver disease is associated with increased deposition of connective tissue in the liver. The aminoterminal propeptide of procollagen type III (P-III-NP) is considered to reflect the metabolism of collagen type III, one of the major collagen types in liver fibrosis. The purpose of the present study was to elucidate, whether S-P-III-NP in patients with viral hepatitis was related to injury and repair processes in the liver. S-P-III-NP was determined in a prospective longitudinal study of 63 patients with acute viral hepatitis followed to healing or development of chronic liver disease. Two assays were applied. The P-III-NP Ria-gnost assay, which measures mainly the intact propeptide, and the P-III-NP Fab-assay, in which the antibody exhibits equal affinity to the intact propeptide as well as the degradation product col 1. At the onset of viral hepatitis, S-P-III-NP determined in either assay was equally elevated in the two groups. From the second month of follow-up, significantly higher levels in both assays were observed in patients developing chronic disease. During follow-up, the highest P-III-NP RIA-gnost values were seen in patients with chronic active hepatitis, and active cirrhosis. S-P-III-NP decreased towards normal levels during development of inactive cirrhosis. In the individual patient, S-P-III-NP Ria-gnost was positively related to transaminases. During follow-up of uncomplicated hepatitis a normalization of transaminases occurred before normalization of S-P-III-NP RIA-gnost. Considering, that S-P-III-NP, in contrast to the conventional laboratory variables, reflects the metabolism of type III collagen, it is assumed that determination of S-P-III-NP may provide new information on fibrogenesis in viral liver disease.