Schistosomiasis is a parasitic disease caused by flat worms of the Schistosoma genus that, in their adult form, infect the portal venous system. Infection with larvae that penetrate the skin occurs whilst patients are bathing in contaminated stagnant freshwater in tropical zones. The invasive phase is characterized by fever, allergic reactions, and hypereosinophilia. During the stationary phase of urinary forms caused by Schistosoma haematobium, the main sign is hematuria. Long-term invasion of the urinary tract may result in terminal renal failure. This species is found in Africa, Madagascar, and in the Middle East. Intestinal and rectal forms cause portal hypertension and are due to S. mansoni (Africa, Madagascar, Latin America, West Indies), S. intercalatum (Central Africa), S. japonicum (Asia) and S. mekongi (Indochinese peninsula). Praziquantel is the drug of choice against all species.
Last update: February 2005