Asymptomatic fascioliasis.

A 72-year-old Japanese man displayed asymptomatic eosinophilia for 4 months. Computed tomography showed multiple space-occupying lesions in the liver. Zoonotic liver flukes were suspected based on occupational exposure to cattle, serological and radiological findings. Immunological examination was helpful in diagnosing the disease and laparoscopy was crucial in confirming Fasciola hepatica and excluding the possibility of malignant hepatic tumors. Human fascioliasis was finally diagnosed and praziquantel administered. Blood eosinophilia resolved within 4 months and liver tumors almost disappeared within 12 months. From our experience, laparoscopy with liver biopsy is very important for diagnosing human fascioliasis, particularly for asymptomatic fascioliasis.