Azygos lobe mimicking pneumothorax in trauma: a case report.

We present a 20-year-old male involved in a high-energy vehicle accident with back pain, chest pain, and a scalp abrasion. A supine chest radiograph revealed a linear lucency in the right apical lobe, raising concern for pneumothorax or a retained foreign body. A contrast-enhanced chest computed tomography (CT) identified an azygos lobe with its characteristic fissure and preserved pulmonary markings, with no evidence of pneumothorax or foreign objects. The patient remained stable and was discharged without intervention. This case highlights the diagnostic challenges of recognizing congenital anomalies like the azygos lobe, present in 0.4%-1.2% of the population, which can mimic critical conditions such as pneumothorax or foreign bodies, particularly in trauma settings. Identifying key imaging features, including the azygos fissure's alignment and normal lung markings, is essential to avoiding misdiagnosis. CT is the gold standard for resolving uncertainty, ensuring accurate diagnosis, and preventing unnecessary interventions in trauma cases.