Intrahepatic bile duct changes in human hepatosplenic schistosomiasis mansoni

Wedge liver biopsies of 132 patients with hepatosplenic mansonian schistosomiasis were studied and divided in two groups according to the presence (Group I – 69 cases) or absence (Group II – 63 cases) of markers of the actual presence of the parasite in the liver tissue. Histological variables indicating bile duct injury were analysed in each case: periductal fibrosis, hyperplasia of the bile duct epithelium, bile duct degeneration, and marginal ductular proliferation. The presence of one or more of these variables defined two sub-groups: A – bile duct lesions present (73 cases), and B – bile duct lesions absent (59 cases). The variables “bile duct degeneration” and “ductular proliferation” were related to the actual presence of the parasite in the host. In 55.3% of all cases of human mansonian schistosomiasis a spectrum of injuries to the bile ducts was present. Epithelial hyperplasia alone or associated with patterns of mucopolysaccharide production was observed in 87.6% cases of the Sub-group A. The bile ducts changes in mansonian schistosomiasis are close to those described in liver fluke infestations such as clonorchiasis, fascioliasis and opistorchiasis. Statistical analysis revealed that high mucopolysaccharide production was associated with epithelial hyperplasia. The pathogenesis of the bile duct changes in human mansonian schistosomiasis and its relation to the parasitic infestations and their antigens is discussed.