Adult Fasciola recovered from the biliary tree in a patient presenting with possible ascending cholangitis and acute acalculous cholecystitis

Background Fascioliasis is a zoonotic trematode infection caused by members of the genus Fasciola ( F. hepatica and F. gigantica ) that localize to the hepatic biliary ducts in humans. Parasites are acquired after ingestion of freshwater plants, and fascioliasis has been reported on every inhabited continent. Typically, fascioliasis is diagnosed by serology or stool examination. This case reports the unusual finding of adult Fasciola organisms during an endoscopic retrograde cholangiopancreatography (ERCP). Case Summary A 65-year-old woman who returned to the United States after traveling in Vietnam presented with abdominal pain, eosinophilia, and cholangitis. Filling defects/debris were detected in the common bile duct (CBD) upon imaging studies, so an ERCP was performed to investigate further. During the procedure, between three and four adult flukes were recovered from the biliary ducts and were later identified as Fasciola at a reference laboratory. Conclusion The recovery of intact Fasciola during a surgical procedure is a highly unusual finding. It is crucial to accurately identify these organisms as there are numerous different species of liver flukes. Some flukes may resemble Fasciola at the egg or adult stage, such as Fasciolopsis buski . The treatment of Fasciola differs from that of all other liver flukes, as it is resistant to praziquantel and must be treated with triclabendazole, and improper treatment can lead to chronic complications.