Question: A 52-year-old man presented with recurrent upper abdominal pain on the right side and fever. On physical examination, there was only mild right side upper quadrant tenderness. Blood tests revealed leukocytosis, mild elevation of direct bilirubin, alkaline phosphatase, glutamic-pyruvic transaminase, and serum carbohydrate antigen 19-9. The serology for hepatitis B virus infection was positive, but alpha fetoprotein levels were normal. Abdominal magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) demonstrated multiple obvious intrahepatic biliary duct cystic and columnar dilatations in the right lobe (Figure A, B).