During a study in Kenya of the relationships between Schistosoma haematobium infection and anemia and growth, evidence was found to suggest that this infection was associated with splenomegaly in children, and that both splenomegaly and hepatomegaly regressed in children treated for urinary schistosomiasis, compared with a placebo group. These results imply that S. haematobium is partially responsible for the splenomegaly and hepatomegaly found in this malarious area, and that treatment for S. haematobium may cause a significant regression of splenomegaly and hepatomegaly in children.