Fascioliasis is infection with the liver fluke Fasciola hepatica, which is acquired by eating contaminated watercress.

F. hepatica is the sheep and cattle liver fluke. Incidental human fascioliasis, acquired by eating watercress contaminated by sheep or cattle dung, occurs in Europe, Africa, China, and South America but is rare in the US.

In acute infection, larvae migrate through the intestinal wall, the peritoneal cavity, the liver capsule, and the parenchyma of the liver before maturing to adulthood. Acute infection causes abdominal pain, intermittent fever, eosinophilia, malaise, and weight loss due to liver damage. Chronic infection may be asymptomatic or lead to intermittent biliary tract obstruction.

CT scans frequently reveal hypodense lesions in the liver. Antibody detection assays are useful in the early stages of disease. Eggs may be recovered in the stool or in duodenal or biliary materials during chronic infection.

Treatment is with triclabendazole, where it is available, or bithionol 30 to 50 mg/kg po every other day for 10 to 15 doses. Treatment failures are common with praziquantel.

Last full review/revision November 2005