Liver involvement in human schistosomiasis mansoni. Assessment by immunological and biochemical markers.

In 20 patients with hepatic or hepatosplenic schistosomiasis and 82 individuals infected with S. mansoni, but without liver enlargement, serum parameters reflecting the fibrotic process and hemodynamic alterations as well as immunomodulation were examined. Included as controls were 35 age- and sex-matched healthy individuals from the study region in Northeast Brazil. Peripheral blood cholylglycine levels in patients with hepatomegaly, reflecting the spillover of portal blood into the systemic circulation, were elevated 12-fold over values of patients without liver involvement. Procollagen-III-peptide, a cleavage product of collagen synthesis, was elevated in patients with hepatomegaly (P less than 0.001) but normal in uncomplicated cases. Immunomodulation was assessed by in vivo delayed hypersensitivity to recall antigens and by serum beta 2-microglobulin and neopterin, substances released in the context of lymphocyte activation. Neopterin, predominantly a macrophage product, was elevated most strikingly in hepatomegalic cases (P less than 0.001). The possible interrelation between altered immune responses and excess fibrogenesis is discussed.