Rare cause of lightning gastrointestinal haemorrhage: pseudoaneurysm of superior mesenteric artery caused by gunshot wound

Comparing to aneurysms, pseudoaneurysms carry a higher frequency of complications, early rupture being the most frequent and dangerous, as it can lead to a life-threatening shock. Traditionally, they are associated with trauma, infection, and inflammatory disease. SMA and branchespseudoaneurysms are the rarest forms of visceral pseudo-aneurysms. Unlike true aneurysms that have all three arterial wall layers, pseudoaneurysms develop from the disruption of intimal and medial layers of the arterial wall and do not contain any epithelized wall, hence the high risk of complications, they are typically outlined by thin fibrous tissue and are usually surrounded by periarterial hematoma. Presentation of pseudoaneurysms may vary from the absence of symptoms to life-threatening haemorrhage and death, but in context of Abdominal penetrating trauma, it can lead to hemorrhagic shock and ischemic colitis. Computed tomography angiography is considered the gold standard for diagnostics.