Ruptured Vertebral Artery Aneurysm in a Patient with Loeys-Dietz Syndrome Type 4: A Sentinel Case Report.

Loeys-Dietz Syndrome (LDS) is a rare, autosomal dominant connective tissue disorder with an estimated prevalence of less than 1 in 100,000. LDS results from one of several genetic mutations altering the transforming growth factor β (TGF-β) signaling pathway. LDS portends a higher risk of vascular pathology including dissections and aneurysms throughout the arterial system. Though not commonly described, this higher incidence of vascular pathology extends to the cerebrovascular system with several case reports of cerebral aneurysms in patients afflicted with LDS. Herein, we describe the case of a 39-year-old female with a family history of cerebral and aortic aneurysms who presented with acute onset headache, neck pain, and lower extremity paresis prompting a CT head and subsequent magnetic resonance angiogram remarkable for a subarachnoid hemorrhage secondary to rupture of a large fusiform V4 segment vertebral artery aneurysm. Formal angiogram confirmed this diagnosis, and endovascular treatment was pursued with coil embolization of the aneurysm and parent vertebral artery distal occlusion. Subsequent genetic testing confirmed the patient to be positive for the mutation indicative of type 4 LDS. Though rare, LDS should be considered as a possible diagnosis in patients presenting with aneurysmal subarachnoid hemorrhage when a family history of systemic vascular pathology is elicited. Confirmatory diagnosis of LDS appropriately spurs additional vascular imaging and family screening to proactively minimize the morbidity of this rare disease.