Rupture of an intracranial aneurysm, an outpouching or sac-like widening of a cerebral artery, leads to a subarachnoid hemorrhage, a sudden-onset disease that can lead to severe disability and death. Several risk factors such as smoking, hypertension, and excessive alcohol intake are associated with subarachnoid hemorrhage (summary by Krischek and Inoue, 2006). For a discussion of genetic heterogeneity of intracranial berry aneurysm, see ANIB1 (105800).

Intracranial berry aneurysms are saccular outpouchings of the intracranial arteries, most commonly at arterial bifurcations, characterized by arterial wall remodeling. Most cases of ruptured intracranial berry aneurysms result in a subarachnoid hemorrhage, associated with high morbidity and mortality (summary by van der Voet et al., 2004). For a discussion of genetic heterogeneity of intracranial berry aneurysm, see ANIB1 (105800).

Autosomal dominant polycystic kidney disease (ADPKD) is generally a late-onset multisystem disorder characterized by bilateral kidney cysts, liver cysts, and an increased risk of intracranial aneurysms. Other manifestations include: cysts in the pancreas, seminal vesicles, and arachnoid membrane; dilatation of the aortic root and dissection of the thoracic aorta; mitral valve prolapse; and abdominal wall hernias. Kidney manifestations include early-onset hypertension, kidney pain, and kidney insufficiency. Approximately 50% of individuals with ADPKD have end-stage kidney disease (ESKD) by age 60 years. The prevalence of liver cysts increases with age and occasionally results in clinically significant severe polycystic liver disease (PLD), most often in females. Overall, the prevalence of intracranial aneurysms is fivefold higher than in the general population and further increased in those with a positive family history of aneurysms or subarachnoid hemorrhage. There is substantial variability in the severity of kidney disease and other extra-kidney manifestations.

Rupture of an intracranial aneurysm (IA), an outpouching or sac-like widening of a cerebral artery, leads to a subarachnoid hemorrhage (SAH), a sudden-onset disease that can lead to severe disability and death. Several risk factors such as smoking, hypertension, and excessive alcohol intake are associated with subarachnoid hemorrhage (summary by Krischek and Inoue, 2006).