Comparative study of Schistosoma mansoni isolated from patients with hepatosplenic and intestinal clinical forms of schistosomiasis.

Six Schistosoma mansoni isolates obtained from the same endemic area were compared experimentally; three were from patients with the hepatosplenic form and three from patients with the intestinal form of schistosomiasis. The following features were analyzed in mice: body weight, liver and spleen weights, mortality, infectivity, number of S. mansoni eggs/female worm, egg distribution in the viscera, and hemogram. Three groups of mice, used as controls, were infected with the LE strain of S. mansoni which is routinely maintained in the laboratory. The group of isolates from patients with the hepatosplenic form of schistosomiasis did not show important differences in relation to those from nonhepatosplenic patients; in almost all features analyzed the differences among these six isolates were within the variation limits observed with the LE strain of S. mansoni.