Missed appendicitis: did unexpected intraluminal densities play a role?

A healthy 19-year-old boy presented to our emergency department with abdominal pain. His history, examination and laboratory evaluation raised concern for appendicitis. A CT study of the abdomen and pelvis was carried out by the radiologist and emergency physician and was notable only for a large amount of unexpected high-attenuation intraluminal material. With further history, this was thought to be most likely retained bismuth from over-the-counter medicine ingestion. The patient was discharged home without a diagnosis. Further review of the CT scan by a second radiologist revealed a concern for appendiceal enlargement and associated free fluid. The patient was called back for further evaluation and treatment and ultimately an appendectomy was performed. Physicians should be aware of the causes and impact of unexpected radiopaque intraluminal contents on radiological studies. Most commonly from ingested medicine, such findings can obscure mucosal details, mimic active bleeding or create a distraction from other abnormalities.