Cannulation of the Common Bile Duct Revealing Numerous Leaf-shaped Worms

A 62-year-old man reported having had fatigue, fever, and cramping abdominal pain for 7 days. He also reported that he had recently eaten raw pond smelt (Hypomesus olidus). The results of liver-function tests were abnormal, showing elevated levels of aspartate aminotransferase (350 IU per liter), alanine aminotransferase (352 IU per liter), alkaline phosphatase (204 IU per liter), {gamma}-glutamyltransferase (434 IU per liter), total bilirubin (6.4 mg per deciliter [109 µmol per liter]), and conjugated bilirubin (3.9 mg per deciliter [67 µmol per liter]). The white-cell count was also elevated (13,000 per cubic millimeter), and there was eosinophilia (27%). A computed tomographic scan of the abdomen showed dilatation of the common bile duct without definite filling defects. Given our concern that the patient might have acute cholangitis, a duodenoscopy was performed, and a prominent major papilla was discovered. After cannulation of the common bile duct, numerous leaf-shaped worms popped out (see video) and w