Abstract
We report a case of human fascioliasis in the USA that encountered many diagnostic uncertainties. Numerous tests available for detection of fascioliasis were utilised but the diagnosis remained elusive. Confounders included three negative stool ova and parasite examinations, positive hepatitis A virus IgM antibody, cross-reactive false-positive Echinococcus IgG antibody, absence of characteristic image findings and unrevealing liver biopsy. Praziquantel was started as empiric treatment for helminth infections, but was ineffective. Due to the rarity of the disease in the USA, serologic testing and triclabendazole were only available from the Centers for Disease Control and Prevention, which led to a delay in diagnosis and treatment.