Appendicitis-mimicking presentation in fishbone induced microperforation of the distal duodenum: A case report

BACKGROUND: Upper gastrointestinal fishbone microperforations are rare and not commonly reported in medical literature. Despite the increasing use of computer tomography (CT) imaging and the employment of the Alvardo criteria, misdiagnosis of acute appendicitis can still occur. We report the rare case of an elderly Chinese gentleman who had a fish-bone induced microperforation of the duodenum that closely mimicked the symptoms of acute appendicitis. CASE SUMMARY: This 79-year-old man presented with migratory lower abdominal pain that localized at his periumbilical region and right lower quadrant. He had associated pyrexia, general malaise and was noted to have an elevated white cell count. CT investigations initially revealed a distended appendix which was resected laparoscopically but showed no obvious signs of gross inflammation. The patient then deteriorated clinically and had increased oxygen requirements immediately after the surgery. This prompted further investigations. A further review of his CT scan revealed a fine fishbone microperforation in the distal duodenum associated with retroperitoneal abscess formation and seepage extending into the right lower quadrant. He was then started on broad spectrum intravenous antibiotics and subsequently underwent a laparotomy 12 h later to manage the obscure aetiology and to drain the abscess. The post-operative course was uneventful and he was discharged 11 d later including a 2-d stay in the intensive care unit. CONCLUSION: This case offers an insight into a potential mimic of acute appendicitis and the diagnostic difficulties experienced in such presentations.