The histopathology of experimental infections in mice with Schistosomatium douthitti.

Abstract

Summary and Conclusions The experimental histopathology of the spleen, intestine, lungs, bone marrow and lymph nodes were studied in mice infected with Schistosomatium douthitti. The inflammatory response in the spleen toward eggs was not as circumscribed as noted in typical pseudotubercles surrounding eggs in the liver. No evidence for an enhanced hematopoietic response or increase in lymphocytic nodules in the white pulp was discerned. In the intestine eggs were found in the submucosa and mucosal lamina propria. Thickening of the serosa and the inhibiting action of the muscularis mucosa in confining eggs and the inflammatory response to the submucosa and muscle layers were noted. In no instance were abscesses of the mucosa seen. In the lungs inflammatory nodules surrounding eggs were observed 60 days after infection. Mature, living worms were seen in the lungs eliciting no apparent cellular response. The histology of the bone marrow, kidney and lymph nodes in infected animals was very similar to that of tissues in the normal, uninfected controls. Comparison of lesions caused by eggs in the spleen of Peromyscus maniculatus, (deer mice) and lesions caused by eggs of S. mansoni in white mice indicated differences in the cellular response of those hosts and may be a reflection of the mechanism of parasite survival.