Regression of hepatic lesions after treatment of Schistosoma mansoni or Schistosoma japonicum infection in mice: a comparative study.

Experimental infections with Schistosoma mansoni and S. japonicum differ in several aspects and post-treatment resorption of fibrosis might be one of them. To investigate this point, mice infected with each of these schistosome species were treated with praziquantel and the evolution of hepatic lesions was sequentially followed for five months. Parasitologic data showing destruction of worms and eggs and biochemical findings of progressively decreased collagen concentration after cure indicated that the lesions caused by S. mansoni and S. japonicum involuted in a similar fashion following chemotherapy. The time sequence of the histologic changes indicative of decreasing inflammation and progressive matrix degradation and resorption was also similar in both cases.