Abstract：
A man in his 70s presented with a sudden onset stabbing back pain radiating to the chest and pre-syncopal symptoms. He underwent urgent investigations, including a CT angiogram aorta which did not reveal any abnormalities within the thorax, abdomen or pelvis and no cause of symptoms was identified. After being discharged, he re-presented 2 days later with syncopal episodes, abdominal pain and a significant drop in haemoglobin levels. This time, a CT mesenteric angiogram showed two hepatic artery pseudoaneurysms and a large haemoperitoneum. Following a hepatic artery embolisation, a workup showed that the likely cause of the pseudoaneurysms was a rare first presentation of polyarteritis nodosa. This case highlights the importance of considering the possibility of an aneurysmal rupture, especially when common causes of an acute abdomen have been excluded, and not relying on previous negative investigations to exclude pathology, as the outcomes can be detrimental.
摘要：
一名70多岁的男子出现突然发作的刺痛，背部疼痛放射到胸部，并出现晕厥前症状。他接受了紧急调查,包括CT血管造影主动脉，没有发现胸部有任何异常，腹部或骨盆，没有发现症状的原因。出院后,两天后他又出现了晕厥发作,腹痛和血红蛋白水平显著下降。这一次,CT肠系膜血管造影显示两个肝动脉假性动脉瘤和大腹膜。肝动脉栓塞后，一项检查显示，假性动脉瘤的可能原因是罕见的结节性多动脉炎。这个案例突出了考虑动脉瘤破裂可能性的重要性，特别是当急腹症的常见原因被排除在外时，而不是依靠以前的阴性调查来排除病理学，因为结果可能是有害的。
