Serum type III procollagen peptide as a non-invasive marker of liver damage during infancy and childhood in extrahepatic biliary atresia, idiopathic hepatitis of infancy and alpha 1 antitrypsin deficiency.

To evaluate the role of serum procollagen III peptide as a non-invasive marker of liver damage and prognosis in hepatobiliary disorders of infancy, we have measured its concentration at presentation and serially in 30 infants with extrahepatic biliary atresia, 22 with idiopathic hepatitis of infancy, 10 with alpha 1 antitrypsin deficiency and 105 age-matched controls. Raised procollagen III peptide concentrations occurred in 51% of patients at presentation and 59% at follow up but were not related to the type of liver disease or the severity of liver damage, as assessed either by standard biochemical tests of liver function, serum glycocholic acid, semiquantitative assessment of 11 histopathological features or hepatic prolyl hydroxylase activity. Serum procollagen III peptide concentrations also gave no guide to prognosis. Although the factors determining serum procollagen III peptide concentrations in hepatobiliary disorders of infancy are unknown at the present time, we suggest that changes in growth rate may be of major importance in determining the significance of serum procollagen III peptide concentrations in infants and children.