Subarachnoid and intraperitoneal hemorrhage secondary to segmental arterial mediolysis: A case report and review of the literature

Background: Segmental arterial mediolysis (SAM) is an uncommon or underdiagnosed arteriopathy that presents with life-threatening hemorrhage. SAM can affect the intracranial, spinal, and visceral arteries, with reported cases of concomitant intracranial and visceral hemorrhage. Case description: We present the case of a 61-year-old male with concurrent subarachnoid and intraperitoneal hemorrhage caused by simultaneously bleeding posterior spinal artery and splenic artery pseudoaneurysms. The posterior spinal artery pseudoaneurysms were treated with selective injection of polyvinyl alcohol particles into the posterior spinal artery, while the splenic artery pseudoaneurysm was treated with Gelfoam embolization. The constellation of imaging, clinical, and laboratory features led to a presumptive diagnosis of SAM, which remains the only reported cause of concurrent neurovascular and visceral artery aneurysm rupture. Conclusion: SAM is a key diagnostic consideration in cases of concomitant intracranial, spinal, and visceral artery aneurysm rupture.