Human Fascioliasis (Liver Fluke Disease) in Hawai'i: Case Report and Review of Human Fascioliasis Acquired in the United States.

Fascioliasis is a foodborne zoonotic infection caused by the trematode liver flukes: Fasciola hepatica and Fasciola gigantica (F. gigantica). Infections may cause acute and chronic hepatobiliary tract diseases in herbivore animals and humans. Fascioliasis is present worldwide, particularly in regions where sheep and cattle are raised. The global burden of human fascioliasis is estimated to be 2.7 million. Human infections are rare in the United States, and most infections were acquired abroad. In the 1950s, several human cases of F. gigantica infection were reported from Hawai'i, but no subsequent cases have been reported until the case described here. This case report describes a man from Hawai'i Island who ate raw wild watercress, and 22 days later, developed acute phase fascioliasis with fever, acute hepatitis, peripheral eosinophilia, and hypodense lesions seen on liver diagnostic imaging. Immunodiagnostic tests were positive for Fasciola species. Based on earlier reports from Hawai'i, F. gigantica infection was likely. Clinical abnormalities resolved after treatment with triclabendazole. Physicians should consider fascioliasis in immigrants and travelers from endemic areas with acute hepatitis and eosinophilia after eating raw wild watercress or chronic hepatobiliary disease. Hepatobiliary imaging and serological testing are useful for diagnosis. Oral triclabendazole is the preferred treatment. Animal fascioliasis appears to be spreading in the United States, and the popularly perceived health benefits of eating raw wild watercress and other aquatic plants may lead to more human infections. The rarity of human infections in Hawai'i suggests that it is safe to eat commercially grown watercress cultivated in Hawai'i.