Diverticulitis-associated colopleural fistula presenting with refractory pneumonia and lung abscess in Korea: a case report

Colopleural fistula, a rare pathological connection between the colon and the pleural cavity, is associated with high mortality and typically requires surgical management. We report the case of a 63-year-old man with colopleural fistula secondary to diverticulitis that progressed to a lung abscess. He was transferred with sepsis and metabolic acidosis in the setting of pneumonia and a left lower lobe (LLL) abscess. During intravenous antibiotic therapy at the referring hospital, he developed uncontrolled epistaxis requiring additional management. His medical history included diabetes mellitus, atrial fibrillation, and prior repair of a perforated gastric ulcer. Despite 5 days of antibiotic therapy, the infection persisted. On hospital day 6, contrast-enhanced computed tomography revealed a fistulous tract between the LLL and the splenic flexure; colonoscopy confirmed diverticulosis with a fistulous communication. Surgical management included left hemicolectomy, adhesiolysis, video-assisted thoracoscopic LLL resection, and diaphragmatic repair. Postoperatively, an intra-abdominal abscess required reoperation, and gastric ulcer bleeding was treated endoscopically. The patient was discharged without further complications. Colopleural fistula should be suspected in cases of lung abscess that are unresponsive to antibiotics; early contrast-enhanced imaging and timely surgical intervention are essential to optimize outcomes.