Saccular intracranial aneurysms in autosomal dominant polycystic kidney disease

The literature on the association of intracranial aneurysms in autosomal dominant polycystic kidney disease (ADPKD) consists mainly of case reports and small series of patients. To provide a more-detailed description of this association and its frequency, the records of all ADPKD patients with saccular intracranial aneurysms, all ADPKD autopsy cases including brain examination, and sex- and age-matched autopsy cases without ADPKD seen at the Mayo Clinic between 1950 and 1989 and of all Rochester residents with a diagnosis of subarachnoid hemorrhage or ADPKD between 1945 and 1984 were reviewed. The presentation of the 41 patients (22 men and 19 women; mean age, 46.4 yr) with this association was subarachnoid hemorrhage in 33, transient ischemic attacks in 2, incidental angiographic or autopsy finding in 5, and discovery during angiographic screening in 1. Thirty-one, seven, and three patients harbored one, two, and three aneurysms, respectively, arising from the middle cerebral artery (N = 23), anterior communicating artery (N = 16), internal carotid artery (N = 11), and vertebral or basilar artery (N = 4). A family history of intracranial aneurysm, subarachnoid hemorrhage, or intracranial hemorrhage at an early age was present in 22% of the patients. Small aneurysms (<5 mm) were less likely to have ruptured or caused symptoms (P <0.04). There was a trend for hypertension to be associated with the severity of the subarachnoid hemorrhage. Aneurysmal rupture occurred before age 50 in 64% of patients. Of the 89 ADPKD autopsy cases with brain examination, 22.5% had intracranial aneurysms. Intact aneurysms, however, were found in only 4.2% of patients who died from causes other than aneurysmal rupture, which was not different from 2.1% in the control group. No clinical features useful in the identification of patients at risk for developing an intracranial aneurysm were detected. ADPKD was diagnosed in 1.7% of the 120 cases of verified aneurysmal subarachnoid hemorrhage in Rochester residents. The findings suggest that (1) intact intracranial aneurysms in ADPKD are less common than appears from the literature, (2) aneurysmal size correlates with the presence of symptoms and the risk of bleeding, and (3) aneurysms may rupture more often and at a younger age as compared with sporadic aneurysms.