A Rare Case of Subarachnoid Hemorrhage due to Rupture of Isolated Anterior Spinal Artery Aneurysm in a Patient with Polycystic Kidney Disease.

Only a very few cases of subarachnoid hemorrhage due to isolated anterior spinal artery aneurysms have been reported in the literature. We report a case of subarachnoid hemorrhage due to anterior spinal artery aneurysm rupture in a renal transplant patient at our institution. A 47-year-old male had abrupt onset of left lower extremity weakness with bowel and bladder disturbances which prompted emergent surgical evacuation of the clot and hence immediate diagnostic angiography was not performed. However, follow-up serial intracranial arterial ultrasound studies showed only vasospasm of the basilar artery. Repeat MRI of the thoracic spine showed persistence of subarachnoid blood products, but no larger foci compared to previous imaging. When spinal subarachnoid hemorrhage is present in the appropriate clinical setting, isolated anterior spinal artery aneurysm should be considered as a possible, treatable cause.