We describe the imaging features of two cases of biliary ascariasis. Ultrasonography and CT showed no specific abnormal findings, but MR cholangiography clearly demonstrated an intraductal linear filling defect that led to the correct diagnosis. MR cholangiography is thus a useful technique for the diagnosis of biliary ascariasis.
Adult ; Animal ; Ascariasis/*diagnosis ; *Ascaris lumbricoides ; *Bile Ducts, Intrahepatic ; Biliary Tract Diseases/*diagnosis/*parasitology ; Common Bile Duct Diseases/*diagnosis/*parasitology ; Female ; Human ; *Magnetic Resonance Imaging

Fascioliasis is a zoonotic infection caused by Fasciola hepatica or Fasciola gigantica. We report an 87-year-old Korean male patient with postprandial abdominal pain and discomfort due to F. hepatica infection who was diagnosed and managed by endoscopic retrograde cholangiopancreatography (ERCP) with extraction of 2 worms. At his first visit to the hospital, a gallbladder stone was suspected. CT and magnetic retrograde cholangiopancreatography (MRCP) showed an intraductal mass in the common bile duct (CBD) without proximal duct dilatation. Based on radiological findings, the presumed diagnosis was intraductal cholangiocarcinoma. However, in ERCP which was performed for biliary decompression and tissue diagnosis, movable materials were detected in the CBD. Using a basket, 2 living leaf-like parasites were removed. The worms were morphologically compatible with F. hepatica. To rule out the possibility of the worms to be another morphologically close species, in particular F. gigantica, 1 specimen was processed for genetic analysis of its ITS-1 region. The results showed that the present worms were genetically identical (100%) with F. hepatica but different from F. gigantica.
Aged, 80 and over ; Animals ; Base Sequence ; Cholangiocarcinoma/diagnosis ; Cholangiopancreatography, Magnetic Resonance ; Common Bile Duct/*pathology ; DNA, Helminth/*genetics ; DNA, Intergenic/genetics ; Diagnosis, Differential ; Fasciola hepatica/*genetics ; Fascioliasis/*diagnosis/parasitology ; Humans ; Male ; Neglected Diseases/diagnosis/parasitology ; Republic of Korea ; Sequence Analysis, DNA