Treatment of Fasciola hepatica Presenting as Biliary Obstruction

A previously healthy 25-year-old man from rural Mexico has been living in the United States for the past 3 years. He presented to our hospital with an acute onset of abdominal pain, nausea, and vomiting. Six months prior he had similar symptoms that improved without further work-up or intervention. Physical examination revealed moderate tenderness in the upper abdomen without hepatosplenomegaly. Laboratory values demonstrated an elevated white blood cell count of 14,500 K/uL (84 % neutrophils, 8% lymphocytes, 7 % monocytes, and 1 % eosinophils) and levels of aspartate amino transaminase of 241 u/L, ala-nine amino transaminase of 264 u/L, total bilirubin of 3.4 mg/dL, and alkaline phosphatase of 297 u/L. His amylase and lipase levels were normal. An abdominal ultrasound scan demonstrated a thickened gallbladder wall and echogenic material within the common bile duct. The intrahepatic and extrahepatic bile ducts were dilated on abdominal computed tomography (CT). The liver, gallbladder, and pancreas appeared normal on CT. He was started on intravenous antibiotics for presumed choledo-cholithiasis causing biliary obstruction. The trematode Fasciola hepatica is a liver flukethat typically infects cattle, sheep, and goats,causing fascioliasis. Humans can become acci-dental hosts of this parasite by ingesting contaminated drinking water or plants such as watercress. Human infections have been reported worldwide, but are most common in Europe, Latin America, the Middle East, and Asia.1 Infection in the United States is uncom