A previously fit 11-year-old boy presented with a 1-week history of abdominal and chest pain, and symptoms worsened for 1 day. He developed a fever of 38.5 C after he was transferred to our institution. His parents denied any other associated diseases. Physical examinations revealed tenderness in his left flank and chest. He was also noted to have decreased breath sounds at the left lung base. His abdominal and chest pain was found to be deteriorated critically by lying down. A routine blood test (RBT) revealed that the white blood cells were 16,900/muL (88.2% neutrophils), hemoglobins were 130 g/L, and C-reactive protein (CRP) was 65 mg/L. Chest and abdominal computed tomography (CT) scan without contrast-enhanced were ordered immediately. Chest CT scan revealed a paraspinal mass in the left posterior mediastinum (Figure 1(a)) and overinflation in the left lower lobe (Figure 1(b)). Pleural effusion was also noted in the left thorax. There were no significant findings on the abdominal CT scan. Therefore, a posterior mediastinal tumor associated with pulmonary infection was considered. Differential diagnoses included congenital pulmonary airway malformation, neuroblastoma, diaphragmatic hernia, or tuberculosis. Upper gastrointestinal contrast study excluded diaphragmatic hernia. Further examinations such as sputum culture and gamma-interferon release test were negative. Serous carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), and neuron-specific enolase (NSE) were also negative. Following the administration of piperacillin/tazobactam for 3 days, his abdominal and chest pain were dramatically relieved, and his fever also subsided. His RBT turned out to be negative after antibiotic therapy. To clarify the characteristics of the posterior mediastinal mass, a contrast-enhanced chest CT scan was conducted. The paraspinal mass was mildly enhanced without significant feeding vessels (Figure 2(a)), and congenital lobar emphysema was considered in the left lower lobe (Figure 2(b)).
Subsequently, this patient underwent video-assisted thoracoscopic surgery (VATS). A 5 x 4 x 4 cm triangular mass covered by visceral pleura with a dark and hemorrhagic appearance was found above the diaphragm (Figure 3(a)). A moderate amount of hemorrhagic pleural effusion was also noted. Severe inflammation and adhesions were observed around the lesion. After isolating the mass from the surrounding tissues, we noticed that the mass was connected to the thoracic aorta by a twisted feeding vessel (Figure 3(b)). The twisted feeding vessel was clamped and divided. A chest tube was left after the operation, and it was removed 3 days later. Postoperative pathology identified infarcted and hemorrhagic lung tissues with cartilages and alveoli. The diagnosis was 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.