Bile duct fascioliasis

A 48-year-old woman who had experienced nausea, vomiting, and right subchondral pain for a month was referred to the gastroenterology clinic because of elevated liver and biliary enzymes.

Her medical history was uneventful except for a cholecystectomy 5 years earlier because of gallstones. She denied using any drugs or alcohol. Laboratory screening revealed abnormal liver and biliary enzymes: alanine aminotransferase 631 U/L, aspartate aminotransferase 536 U/I, alkaline phosphatase 185 IU/mL, γ-glutamyl transferase 286 IU/I, total bilirubin 1.2 mg/dL, and direct bilirubin 1 mg/dL. The results of a hemogram and other blood biochemistry tests; viral serology including hepatitis A, B, and C; and tests for Toxoplasma gondii, other infections, rubella virus, cytomegalovirus, and herpes simplex virus were unremarkable.

Upper abdominal US revealed the common bile duct (CBD) to be 9 mm in diameter, and there was no stone. Unfortunately, we were unable to see the distal CBD because of shadowing caused by duodenal gas. However, endosonography revealed a mobile fluke floating inside the mildly dilated CBD, confirming a diagnosis of Fasciola hepatica infection. She was treated with 3 weeks of metronidazole 500 mg 3 times per day. At the end of the therapy, repeated endosonography showed an immobile fluke in the CBD (Fig. 1). A sphincterotomy was performed, and the dead fluke was removed from the CBD during ERCP (Figs. 2 and 3; Video 1, available online at www.VideoGIE.org).

Figure 1.

EUS view of abdomen showing dead parasite.

Figure 2.

ERCP view showing extraction of the dead parasite from the common bile duct.

Figure 3.

Dead parasite after removal from the bile duct.

Fascioliasis is a foodborne hepatic trematode zoonosis caused by Fasciola species. The parasites infect humans who ingest the metarcercariae found in contaminated freshwater plants.¹ Human infection is common in developing countries and also in Europe.¹ The diagnosis of this infection may be challenging because the history and symptoms are nonspecific. It is often difficult to diagnose and test for stool analysis for eggs in a patient with right upper-quadrant pain and elevated liver and biliary enzymes. Upper abdominal US can be helpful in the diagnosis of biliary fascioliasis. It can reveal biliary dilatation and irregular thickened walls, and worms can be seen as vermiform structures without acoustic shadowing.² However, worms hidden in the distal biliary tree may be missed, as in the present case.²

Endosonography has become important in accurate investigatory imaging of the lower biliary tree. Its role in the diagnosis of biliary fascioliasis has been established, and this imaging method clearly helped us to make the diagnosis with 100% accuracy.² Medical treatment includes triclabendazole, bithionol, nitazoxanide, and metronidazole, but biliary obstruction may require ERCP and direct removal of the parasites after medical therapy.3, 4

Disclosure

All authors disclosed no financial relationships relevant to this publication.

Supplementary data

Video 1

Biliary fascioliasis: an EUS-guided diagnosis and feasible treatment approach.