Serum laminin and type III procollagen in chronic hepatitis C. Diagnostic value in the assessment of disease activity and fibrosis

Laminin P1 (pepsin-resistant fragment of laminin) and aminoterminal peptide of type III procollagen are measurable in serum and are now considered useful serum markers of fibrogenesis and inflammation in chronic liver diseases. However, very few studies thus far have focused on assessing the diagnostic value of these markers in detecting fibrosis and necro-inflammatory activity in chronically diseased liver. The aim of the present study was therefore to investigate the correlations of laminin and type III procollagen with liver histology and to compare their diagnostic value in detecting the degree of liver fibrosis and necro-inflammatory activity in a homogeneous group of 99 patients suffering from chronic hepatitis C, and lacking other factors which can directly affect the serum levels of the two markers. Both these serum markers were measured by radioimmunoassay, employing commercially available kits. The three main aspects of liver pathology, i.e. portal-periportal activity, lobular activity and fibrosis, were histologically evaluated and semiquantitatively expressed by numerical scores. The results of this study show that laminin and type III procollagen were both positively correlated with the histological scores for portal-periportal activity and with those for fibrosis, whereas no significant correlation was observed between each of the two serum markers and the histological scores for lobular activity. The sensitivity and specificity of laminin and type III procollagen in detecting histological aspects of fibrosis and disease activity in liver, computed at various cut-off levels, showed overlapping trends for the two markers; however, the diagnostic value was in general rather low, whatever the cut-off considered. We therefore conclude that the 'static' measurement of both serum laminin and type III procollagen is of limited value for invidiual diagnosis of liver damage.