Distomatoses

Distomatosis are parasitic zoonosis caused by infection with trematodes ; humans can accidentally become the definitive host of the parasite. Infection occurs by ingestion of contaminated food (plants or raw shellfish). Clinical manifestations depend on the tropism of the fluke : hepatobiliary for fasciolasis and opisthorchiasis, pulmonary for paragonimiasis, or intestinal. Infection with Fasciola hepatica is a world-wide disease ; the other distomatosis are endemic in Africa, South America and Southeast Asia. Diagnosis, suspected in front of epidemiological facts (stay in endemic area, food habits) and hypereosinophilia, is based on the identification of the parasite or its eggs, and on serology. Drugs of choice are praziquantel, bithionol, and triclabendazole whose effectiveness, good tolerance and single dose make it now the first choice treatment. Endoscopic management is useful in biliary obstruction. Suppression of risk factor is the best way for preventive approach.