An unusual cause for a relatively common radiographic abnormality

A 59-year-old Indian woman presented to the respiratory clinic with chest pains, long-standing swallowing difficulties and a chest radiograph, which was reported as showing a shadow in the right paratracheal region. A CT scan was obtained and was reported as demonstrating a right-sided paratracheal lymph node and varicosities adjacent to the inferior vena cava. Histology from an endobronchial ultrasound-guided biopsy revealed a heavily blood-stained sample but showed no evidence of granulomas or malignancy. Subsequently, the images were reviewed, with the conclusion that they were actually of an engorged azygos vein compressing the oesophagus. MRI confirmed the absence of mediastinal lymphadenopathy and the presence of a prominent hemiazygos vein compressing the oesophagus. This case highlights the importance of including anatomical abnormalities in the differential diagnosis and reassessing patients when the history and investigations do not correlate.