Image Diagnosis: Worm-Induced Biliary Obstruction.

CASE REPORT A 57-year-old woman born in the Philippines presented to the Emergency Department with 6 hours of epigastric and right upper quadrant abdominal pain radiating to her back. She denied fever, nausea, and vomiting. She described her pain as similar to pain before her cholecystectomy 46 years previously, at age 11. An ultrasound demonstrated a hyperechoic linear structure in the common bile duct and diffuse biliary duct dilation (Figure 1) that were initially read as consistent with a nonfunctioning stent, which the patient denied having. The computed tomography scan of the abdomen and pelvis that was ordered to better characterize the “stent” demonstrated only biliary dilation in the common bile duct without a radiopaque structure (Figure 2). Laboratory test results for the patient’s complete blood count, comprehensive metabolic panel, and lipase were normal. Because biliary stents were not available in 1958 when the patient underwent her cholecystectomy, and because the ultrasound abnormality was hyperechoic without radiopaque characteristics, we considered the possibility of a biliary worm.1 An endoscopic retrograde cholangiopancreatography (ERCP) showed the presence of a worm, extending from the ampulla into the bowel lumen. During attempted retrieval of the worm, it retracted into the bile duct, and only a large, transected portion was removed. Our patient tolerated the procedure well and was later released from the hospital.