Occult transgastric fish-bone migration causing delayed left hepatic abscess: serial computed tomography findings and a missed diagnostic opportunity

Ingested fish bones rarely perforate the gastrointestinal tract and migrate into the liver, and the diagnosis may be delayed when ingestion is not recalled and the perforation is locally contained. We report a 45-year-old man who presented with nine days of intermittent fever, upper abdominal distension, and frequent belching. Ultrasonography demonstrated a large complex collection in the left hepatic lobe with an internal echogenic focus. Non-contrast computed tomography showed a multiloculated left-lobe abscess containing a 5-cm linear hyperattenuating foreign body, focal discontinuity of the gastric antral wall, and hepatogastric inflammatory adhesion. Retrospective review of a chest computed tomography examination performed approximately four months earlier showed the same linear foreign body extending from the gastric antrum towards the left hepatic lobe while the adjacent hepatic parenchyma was still normal; the finding had not been reported initially. Laparoscopic drainage yielded approximately 200 mL of pus and enabled intact removal of a 5-cm fish bone, followed by clinical and imaging improvement. This case provides direct serial-imaging evidence of occult transgastric migration preceding hepatic abscess formation. It highlights the importance of reviewing all imaged anatomy, including scan margins, using multiplanar reformations for linear foreign bodies, comparing prior examinations, and identifying and removing a retained foreign body when it is the source of infection.