Diagnosis of upper gastrointestinal perforation complicated with fistula formation and subphrenic abscess by contrast-enhanced ultrasound: A case report

BACKGROUND: Gastrointestinal perforation complicated by subphrenic abscess is a surgical emergency. Its diagnosis relies mainly on X-ray or computed tomography (CT), while the value of ultrasound, especially contrast-enhanced ultrasound (CEUS), has been underestimated. CASE SUMMARY: A 37-year-old man presented with fever and edema of the lower extremities for 10 d. He had a history of laparoscopic repair of gastroduodenal perforation 6 mo prior. His first-time intravenous CEUS indicated a diagnosis of subphrenic abscess. He received antibiotic therapy and ultrasound-guided percutaneous drainage of the abscess. However, second-time intravenous CEUS revealed an unsatisfactory therapeutic effect. Intracavitary CEUS was proposed, and this examination detected communication between the abscess and the stomach. Upper gastrointestinal perforation complicated by fistula formation and subphrenic abscess was diagnosed with the help of CEUS. Abdominal CT and esophagogastroduodenoscopy confirmed the diagnosis. The patient recovered after the perforation was repaired by surgery. CONCLUSION: Intravenous and intracavitary CEUS provides helpful information for the diagnosis of upper gastrointestinal perforation complicated by fistula formation and subphrenic abscess.