Torsed extralobar pulmonary sequestration associated with congenital lobar emphysema: a rare entity.

Pulmonary sequestration (PS) is a rare congenital malformation, which mainly contains two variants involving extralobar and intralobar sequestrations. Extralobar sequestrations (ELS) are isolated from the remaining lung tissue and have their visceral pleura. Herein, we report the first case of a torsed ELS associated with congenital lobar emphysema. We described a boy who mainly presented with abdominal and chest pain. A contrast-enhanced computed tomography (CT) scan revealed a mildly enhanced posterior mediastinal mass with left lower lobar emphysema. Thoracoscopic surgery identified a dark and hemorrhagic mass that was connected to the thoracic aorta by a twisted feeding vessel and had its visceral pleura. Pathological findings were consistent with an ELS that had undergone torsion and infarction. The postoperative recovery was uneventful. For the left lower lobar emphysema, he was required for a regular outpatient follow-up. In conclusion, although extremely rare, physicians should maintain a high index of suspicion for torsed ELS when a posterior mediastinal mass with abdominal or chest pain is presented in children.