INTRODUCTION: A pneumatocele is a cystic change in the lung that can develop as a sequelae of infection, inflammation, positive-pressure ventilation, thoracic trauma, and rarely after lung resection. Pneumatocele development triggered by an extrathoracic etiology is rare. Herein, we report a case of a pneumatocele that developed after a deceased-donor liver transplantation. CASE PRESENTATION: A 57-year-old woman with a diagnosis of autosomal dominant polycystic kidney disease underwent deceased-donor liver transplantation for polycystic liver disease. She did not have any background lung disease, although her right lower lobe was mostly atelectatic due to a remarkably elevated diaphragm. The liver transplant itself was uneventful. A small hole was made in the right diaphragm during the dissection of the liver, but it was successfully repaired without any injury to the lung. On postoperative day 1, the chest radiograph revealed a round hypertranslucency on the right side, which was initially considered subphrenic air retention, and no further evaluation was made at that time. Given that the hypertranslucency persisted, follow-up computed tomography was performed on postoperative day 18, and revealed an air-fluid level above the diaphragm in the right thoracic cavity. Thoracoscopic investigation revealed an intrathoracic hematoma within a pneumatocele in the right lower lobe, which was not detected in the pretransplant computed tomography. The hematoma was removed, and the pneumatocele was resected. CONCLUSIONS: We experienced a case of a pneumatocele that developed after deceased-donor liver transplantation for multiple hepatic cysts due to autosomal dominant polycystic kidney disease. Although the mechanisms are speculative, the pneumatocele might have been triggered by the sudden alleviation of the elevated diaphragm and reinflation of the atelectatic lung.
