Azygos vein dilation has been described in patients with portal vein hypertension, obstruction of superior or inferior vena cava, right heart failure and interruption of the inferior vena cava (IVC). Interrupted IVC with azygos continuation is a rare clinical condition but in this situation, the azygos system dilates to accommodate visceral and lower the extremity of blood return to the right atrium. Although uncommon, these anomalies have been described as an isolated finding and can mimic a mediastinal mass [1,2,3,4]. If isolated interrupted IVC with azygos continuation is together with lung carcinoma, it can be misinterpreted as a lymphadenopathy in a patient who has been evaluated with unopacified CT scans.We present a case of isolated azygos continuation of the interrupted IVC mimicking a paraesophageal lymph node enlargement in a patient with a left hilar mass.
Case reportA 68-year-old man was admitted to our hospital presenting a left tumour mass and lymphadenopathy on unopacified Computed Tomography scan of the chest and metastasis of the first and fourth lumbal vertebrae on Magnetic Resonance Imaging. The physical examination revealed a non-healthy man. He was febrile (37.5°C) and had a blood pressure of 150/100 mmHg, a heart rate of 100 beats/min. Breath sounds were diminished on both lungs. The heart and abdominal examinations were unremarkable. The neurological examination was significant for paralysis in both lower extremities. A posteroanterior chest x-ray revealed a left hilar mass. Contrast-enhanced spiral CT scan of the chest showed a tumour mass at the superior segment of the lower left lobe with invasion of the descending aorta and dilated azygos vein (figure 1), mild enlargement of the arch of the azygos, and enlargement of the retrocrural portions of these same veins in the absence of definable inferior vena cava (figure 2). Coronal (figure 3) and sagittal reconstructions showed that the azygos vein was as large as the descending aorta.Fiberoptic bronchoscopy showed no endobronchial lesion except of narrowing and mucosal hyperemia of the superior segment of the lower left lobe. The cytopathologic examination of the brushing and washing specimens was benign.In a routine ultrasound examination of the abdomen, the stomach, heart, liver and spleen were normally positioned and the gallbladder was present. A detailed ultrasound examination of the IVC was not carried out owing to the patient's poor health.Diagnosis of our patient was accepted to be lung carcinoma with bone metastasis and palliative radiotherapy planned. However, our patient did not accept the treatment and was discharged.
DiscussionThe azygos vein usually originates below the diaphragma at the level of the first two lumbal verKeywords: Azygos vein, vascular anomaly, mimicking lymph node.