Case Presentation:
59 year old African American male presented to our emergency department with chills, night sweats and not feeling well. Chest x-ray showed a left upper lobe opacity and was diagnosed with community acquired pneumonia and discharged on Levaquin. Three days later, he presented to the ER, with an episode of hemoptysis. Medical history is significant for hypertension. He smokes cigarettes, marijuana and drinks alcohol every day. Physical exam revealed an ill appearing middle aged man. He was tachycardic and otherwise unremarkable except diminished breath sounds in left apex.
Laboratory tests showed an elevated creatinine of 4.2 mg/dl and WBC count of 18,500/dl with neutrophilic predominance. Chest x-ray demonstrated worsening left upper lobe opacity. A CT chest showed a cavitating left upper lobe mass in contact with the aortic arch. Given the constellation of symptoms and CT findings, he was diagnosed with possible necrotizing pneumonia in the setting of aspiration from alcohol and started on broad spectrum antibiotics. Cardiothoracic surgery was consulted in the interim. CT angiography of chest done to further delineate aortic pathology revealed a contained rupture of proximal descending thoracic aorta in contrary to previous imaging. Patient underwent emergent thoracic endo vascular aortic aneurysm repair. Postoperative period was uneventful and later discharged home.
Discussion:
Aortic dissection and contained rupture of aorta are life threatening medical emergencies. While aortic dissection may be relatively easy to diagnose, contained rupture of aorta is quite challenging as it has a distinctly different presentation of subacute or chronic and these patients are hemodynamically stable. Unfortunately, identification of this condition gets much more difficult when it is disguised as a different pathology or presents in an atypical fashion. But prompt diagnosis of contained rupture is still important because of the imminent danger of exsanguination if undetected. This is an interesting case of contained rupture of proximal descending thoracic aorta masquerading as necrotizing pneumonia.
Conclusions:
This case is not only interesting, but also gives us important learning points. A high-attenuation “crescent” in the mural thrombus of Thoracic Aortic Aneurysm in CT may represent an acute contained or impending rupture. Another sign is the “draped aorta sign,” wherein the posterior aortic wall is closely opposed to the spine. Even if there are no obvious signs, obscuration of the lung interface with the transverse or descending thoracic aorta such as our case should still be viewed with suspicion and further investigation is warranted. Any aortic pathology if not timely diagnosed can be fatal and prompt diagnosis is crucial to prevent mortality.